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  • 1
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The mound builderMacrotermes michaelseni forages in Kenya semi-arid pastures. Each colony (4/ha) utilizes 130 to 600 m2 in average per month. The distribution of foraging holes 22 000 to 50 000 per nest) shows an overall spatial activity. The 24h foraging activity is mainly nocturnal and the seasonal variation presents three peaks per year. This activity depends partly on temperature and rainfall but the internal economy (sexual brood production within the colony) plays a decisive role.
    Notes: Resume Macrotermes michaelseni est un constructeur de termitières épigées qui récolte en strate herbacée dans les pâturages semi-arides du Kenya. Chaque colonie (4/ha) exploite en moyenne 130 à 600 m2 par mois. La répartition des orifices de récolte (22 000 à 50 000 par colonie) démontre que l'ensemble du milieu est utilisé. On envisage la variation journalière de l'activité de récolte (essentiellement nocturne) ainsi que sa périodicité saisonnière (3 maximums annuels). Cette activité est partiellement reliée à la température et aux pluies, mais l'économie interne des colonies (production du couvain de sexués) est aussi déterminante.
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  • 2
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    Insectes sociaux 28 (1981), S. 341-342 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Nestgründung von einer Arbeiterin der japanischen Falten WespePolistes chinensis antennalis wurde im Juni 1979 beobachtet. Diese Arbeiterin ausschlüpft im Juni 1979 aus einem anderen Nest und reparierte ein verlassenes Nest und zog darin einige Larven aus. Diese ist die erste Entdeckung der Nestgrüdung von einer Arbeiterin in der Unterfamilie Polistinae.
    Notes: Summary The nest foundation by a single worker of the Japanese paper waspPolistes chinensis antennalis was observed in July, 1979. This worker had emerged from another nest in June 1979, and repaired an abandoned nest and reared some larvae there. This is the first discovery of nest foundation by a worker in the subfamily Polistinae
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  • 3
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The present work follows the study ofMacrotermes michaelseni foraging activities (Lepage, 1981) and deals with its food requirements. The yearly food offtake ranges between 800 and 1500 kg/ha. The harvest is 25 to 30% below in lean year (1976). Termites and large mammals offtakes are similar but they take place at different times of the ecosystem cycle: rainy season for mammals and dry season for termites.Macrotermes would prefer grass litter on the ground if available, but can switch to standing crop as the ecosystem becomes more arid. From this work it is possible to understand howMacrotermes could be a pest in these pastures.
    Notes: Resume Cette étude envisage la prise de nourriture du termiteMacrotermes michaelseni en strate herbacée et complète les observations rapportées précédemment sur le cycle de récolte du termite (Lepage, 1981). Le prélèvement varie de 800 à 1500 kg/ha/an et il est de 25 à 30% inférieur lorsque l'année est déficitaire en pluies (1976). Cette récolte est comparée à l'action des grands Mammifères herbivores présents sur le lieu de l'étude: les quantités globales (herbe et litière) sont du même ordre. Mais l'impact sur l'écosystème n'intervient pas au même moment: saison des pluies pour les Mammifères, saison sèche pour les termites.Macrotermes préfère la litière graminéenne au sol mais consomme progressivement l'herbe sur pied à mesure que l'écosystème devient plus aride. Il est possible de comprendre, d'après ces observations, commentMacrotermes peut devenir nuisible pour ces pâturages semi-arides.
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  • 4
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    Insectes sociaux 28 (1981), S. 347-352 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Ungefähr 18% der Arbeiterinnen vonLasioglossum zephyrum werden unter natürlichen Freilandbedingungen begattet. In der Gefangenschaft variiert die Bereitschaft der Weibchen zur Begattung mit dem Alter und dem Kastenzustand: 1) Von anderen Weibchen isolierte Weibchen paarten sich zu 69% innerhalb von drei Tagen nach dem Schlüpfen. 2) In Nestgruppen von je sechs Bienen paarten sich alle Königinnen, jedoch nur 7,7 % aller Arbeiterinnen. 3) Nach künstlicher Entfernung der Königin verpaarten sich die Ersatzköniginnen in allen von zehn Fällen. Diese Ersatzköniginnen waren alle vorher in Gegenwart der alten Königin unverpaart. 4) In einer Kolonie von fünf Bienen paarten sich alle drei Ersatzköniginnen nachdem der Reihe nach die jeweilige Königin entfernt worden war. Gleichzeitig wurden keine der jeweiligen Restarbeiterinen begattet. Diese Ergebnisse zeigen an, dass die Königin die Paarungsbeitschaft der Arbeiterinnen auch ausserhalb des Nestes inhibiert. Es erscheint möglich, dass sich Inhibition durch eine Königin nicht nur auf die Grösse der Ovarien von Arbeiterinnen auswirkt.
    Notes: Summary About 18 percent ofLasioglossum zephyrum workers mate in the field. In the laboratory female mating receptivity varied with age and caste: 1) sixty-nine percent of bees less than 3 days old mated when kept isolated from other females, 2) in six-bee colonies all of the queens, but only 7,7 percent of their workers, mated, 3) in queen removal experiments involving 10 colonies, all the replacement queens mated (these same individuals were not receptive to mating as workers), 4) in one colony of 5 bees, consecutive queen removal showed that each of the four bees identified as the queen mated, while none of the remaining workers did so. The results indicate that queen inhibition governs behavior of the workers even outside the nest. The inhibition may involve more than differences in ovarian size.
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  • 5
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    Insectes sociaux 28 (1981), S. 353-370 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary Workers ofMyrmica rubra cluster around living queens from their own colony. Workers also cluster around these same queens after they are killed and kept for one or two hours. The suggestion is that the factors causing these aggregations are at least partly chemical, for dead queens are unable to give movement or acoustical signals. Also, the form of the queens'body is unable to induce the clustering response. The chemical signals causing aggregation, emitted by the queen, are not very volatile and/or they are well adsorbed by her cuticle. They oxidise rapidly after 3–4 hours exposure to the air and they continue to denature, losing their ethological activity, for the subsequent 2–3 days. They deteriorate when warmed to a temperature of 50°C for a few minutes. Organic solvents denature them rapidly and may extract them whereas distilled water has no effect upon them. The chemical factors are uniformly distributed over the external surface of the queen's body and it seems that they are not produced by the metapleural glands. The experiments, producing the above results, are detailed and discussed raising questions and hypotheses that we will consider in future work.
    Notes: Resume Les ouvrières deMyrmica rubra s'agrègent autour de reines indigènes vivantes, et de ces mêmes reines mortes depuis 1 ou 2 heures. Les facteurs responsables de ces agrégations sont, au moins partiellement, de nature chimique. Ils ne sont ni gestuels, ni acoustiques, et la forme du corps des reines est incapable, à elle seule, d'agréger les fourmis. Les facteurs chimiques agrégatifs propres aux reines sont peu volatiles et/ou bien adsorbés sur la cuticule des reines. Ils s'oxydent à l'air au bout de 3 ou 4 heures puis se dégradent encore d'une autre manière, progressivement, au cours du temps. Un passage de quelques minutes à une température voisine de 50°C les altère. Les solvants organiques, mais non l'eau distillée, les dénature rapidement et les extraient peut-être. Enfin, ces facteurs chimiques se répartissent uniformément sur toute la surface externe du corps des reines, et ils ne semblent guère provenir des glandes métapleurales. Après avoir détaillé nos travaux, puis discuté des renseignements acquis, nous posons des questions et hypothèses à envisager dans la suite de notre étude.
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  • 6
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume La «fourmi de feu»,Solenopsis invicta Buren, a trois principaux groupes fonctionnels d'ouvrières: les fourrageuses, les «stockeuses de réserves» et les nourrices. En utilisant un nid spécialement construit, nous avons pu séparer ces groupes fonctionnels. Nous avons donné aux fourmis de l'iode radio-actif (1251) mélangé à de la poudre de jaune d'œuf, de l'huile de soja ou une solution de miel à 50 % pendant 10 minutes. Le nombre de fourmis par nid et la quantité de nourriture marquée, consommée par fourmi, ont ensuite été mesurés. Lorsqu'elles ont reçu du miel ou de l'huile de soja, les colonies répondent en augmentant le nombre de fourrageuses et de «stockeuses de réserves» actives. Avec les deux sortes de nourriture, les fourrageuses consomment de grandes quantités de liquide; elles en transmettent des quantités plus petites aux «stockeuses de réserves» et aux nourrices. Lorsqu'on donne du miel «à 50 %» aux fourmis, moins de 0,2 % du miel recueilli par les fourrageuses parvient à la colonie; seulement 5 % des larves sont nourries après 10 minutes. Lorsqu'on donne de l'huile de soja, 2 % de l'huile recueillie parvient aux larves: à peu près 35 % des larves sont nourries après 10 minutes. Lorsqu'on donne de la poudre de jaune d'œuf, le nombre de fourrageuses est bas, mais celles-ci viennent plusieurs fois; elles laissent la nourriture à la périphérie du nid ou la transmettent aux «stockeuses de réserves». Les «stockeuses de réserves» transmettent rapidement la nourriture aux nourrices de sorte que, par rapport à l'huile et au miel, la quantité de nourriture consommëe par fourmi est la plus élevée parmi les nourrices. A peu près 80 % du couvain est nourri avec de la poudre de jaune d'œuf durant la période de 10 minutes, ce qui représente 6 % du jaune d'œuf recueilli par les fourrageuses. De cette étude, il apparaît que les ouvrières peuvent distinguer différents types de nutriments et, en conséquence, adapter leur comportement.
    Notes: Summary The imported fire ant,Solenopsis invicta Buren has three main functional worker groups: foragers, reserves, and nurses. By using a specially designed nest we were able to separate these functional groups by location. The ants were presented with 125 Iodine mixed with egg yolk powder, soybean oil, or 50 % honey solution for 10 minutes. The number of ants per nest location and the quantity of radiolabelled food consumed per ant were then measured. When presented with honey or soybean oil, colonies responded by increasing the number of foragers and active reserves. With both foods the foragers took in large quantities of liquid, passing on smaller amounts to the reserves and the nurses. When ants were presented with 50 % honey, less than 0.2 % of the honey collected by the foragers reached the brood. Only 5 % of the larvæ were fed after 10 minutes. When soybean oil was presented, 2 % of the oil collected reached the larvæ and approximately 35 % of the larvæ had been fed after 10 minutes. When the ants were presented with egg yolk powder, the number of foragers was low but they made repeated trips, leaving food on the nest periphery or passing it on to the reserves. Reserves relayed food rapidly to the nurses so that, in contrast to oil and honey, the quantity of food consumed per ant was greatest among the nurses and lower among the reserves and the foragers. Approximately 80 % of the brood were fed egg yolk powder within the 10 minutes period receiving 6 % of the egg yolk collected by the foragers. From this study it appears that workers can discriminate between nutrient types and adjust their behaviour accordingly.
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  • 7
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    Insectes sociaux 27 (1980), S. 29-42 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Cephalotes atratus, la «Fourmi-tortue géante», de la tribu néotropicale des Cephalotini, apparaît comme un stade intermédiaire dans l'évolution du polymorphisme social. La ligne de croissance allométrique est droite, mais la distribution des tailles des ouvrières est bimodale. Un éthogramme des ouvrières dans des nids artificiels montre des différences de comportement prononcées en fonction de l'âge. Dans les conditions naturelles, on observe aussi des spécialisations du comportement individuel d'approvisionnement, en rapport avec la taille des ouvrières. Comparée à d'autres Céphalotines évoluées, cette espèce semble moins fortement modifiée dans le sens de la vie arboricole. On présente un modèle d'évolution du polymorphisme chez les Fourmis.
    Notes: Summary Cephalotes atratus, the “giant turtle ant” of the Neotropical tribe Cephalotini, exhibits an intermediate stage in the evolution of polymorphism. The allometric growth line is straight, but the distribution of worker sizes is bimodal. An ethogram of workers in laboratory nests showed pronounced differences in behavior according to age. Under natural conditions, individual foraging specializations based on worker size were also found. Compared to other advanced cephalotines, this species appears to be less strongly adapted for arboreal life. A model is presented for the evolution of polymorphism in ants.
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  • 8
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    Insectes sociaux 27 (1980), S. 97-107 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Chez des femelles dePolistes gallicus, nous avons examiné le volume des corpora allata et leur activité de synthèse in vitro estimée grâce au dosage radiochimique de l'hormone juvénile. Les valeurs obtenues sont comparées avec l'activité ovarienne. Pendant la première période de maturation des ovocytes, à la sortie de l'hivernage, le volume des corpora allata est en nette corrélation avec leur activité de synthèse. Cependant, chez des femelles hivernantes ou ovariectomisées, nous avons observé de très grosses glandes ne produisant que de petites quantités d'hormone juvénile. Les petits corps allates des femelles stylopisées ont une activité de synthèse très faible. Chez toutes les femelles dominantes, les corpora allata sont plus grands et plus actifs que chez les subordonnées; les changements d'activité endocrinienne semblent liés à l'établissement d'une hiérarchie sociale entre les fondatrices.
    Notes: Summary In females ofPolistes gallicus the activity of corpora allata (CA) was determined volumetrically as well as radiochemically using the in vitro assay for juvenile hormone (JH). The results we have compared with the ovarian activity. During the period of egg maturation after overwintering the volume of CA is well correlated with the synthetic activity. But in overwintering females and in ovariectomized females we have observed very large glands which produced only little amounts of JH like the small glands of parasitized wasps. In all dominant females the CA we have found to be larger and more active than in subordinated females indicating that changes in the endocrine activity may be a primary result of social hierarchy.
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  • 9
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    Insectes sociaux 27 (1980), S. 127-147 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Le déménagement de sociétés deMyrmica rubra L. a été induit en laboratoire en dégradant le microclimat des nids. L'analyse détaillée du processus de déménagement s'appuie sur l'observation et sur la mesure du trafic entre l'ancien et le nouveau nid. On distingue trois phases: l'exploration, l'émigration, et l'exploration finale.Myrmica rubra utilise deux modes de recrutements initiés par des comportements d'invitation distincts: les recrutements de groupe dominent au début, les transports par la suite. L'organisation du groupe est étudiée. Le «leader» émet une phéromone issue de l'appareil à venin. Nous avons tenté d'en préciser l'origine glandulaire (glande de Dufour ou glande à poison) par des expériences de leurre et l'analyse de traces sur du noir de fumée. La plupart des transports se font selon la position typique des myrmicines; la signification des transports atypiques est discutée. Le transport de compagnes ou de couvain est effectué par 25% des ouvrières (en moyenne), dont la majorité montre une forte pigmentation cuticulaire. La stabilité de ce groupe d'ouvrières transporteuses est testée au cours de déménagements successifs. Le pouvoir de régulation sociale est élevé: des reines ou des jeunes ouvrières isolées du reste de la colonie peuvent mener un déménagement à bien.
    Notes: Summary The colony-moving ofMyrmica rubra L. was induced in he laboratory by worsening the microclimate of the nest. A detailed analysis of the whole process is given; it is based both on observation and on traffic measurements between the old and the new nests. Three periods can be recognized: exploration, emigration, and final exploration. Two recruitment methods occur, initiated by distinct motor displays: group recruitment takes place first, whilst carrying behaviour becomes the main technique later. The organization of the group is described. The recruiter extrudes its sting while returning to the old nest and while leading the group. Tracks left on soot-coated glasses are analyzed. Sticks crushed with either the poison gland or the Dufour's gland are effective in leading the ants. Most adult carrying postures are typical for myrmicines: the occurrence of atypical postures is discussed. All the carrying acts (of brood and adults) are effected by 25% of the workers (on average); carrying activity is age-dependent. The stability of the group of carriers is tested during successive emigrations. Social regulation potentiality is strong: even queens or callows can move with their larvae when isolated from the rest of the colony.
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  • 10
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    Insectes sociaux 27 (1980), S. 391-398 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Le taux de reproduction d'abeilles de races européennes non domestiquées a été étudié dans le Kansas (U.S.A.). Chaque colonie avec la même reine a produit 3,6 coloniesfilles en moyenne pendant un an. Ce taux de reproduction élevé est essentiellement dû à des essaims secondaires; ce facteur n'a pas été suffisamment considéré jusqu'à présent. Le taux d'essaimage secondaire est influencé par au moins deux facteurs: la quantité de couvain operculé dans la colonie et la saison où l'essaimage se produit. Nous discutons aussi les facteurs qui peuvent affecter la survie et la reproduction des essaims primaires et secondaires.
    Notes: Summary The reproductive rate of unmanaged European honeybee races was studied in Kansas, U.S.A. Colonies produced a mean of 3.6 daughter colonies per original queen during one year. This high reproductive rate was largely due to the frequent occurrence of afterswarms, a factor not adequately considered in previous studies. The rate of afterswarming was influenced by at least two factors: the amount of sealed brood (pupae) in the colony and the season when swarming occurred. Factors which may influence the survival and subsequent reproduction of prime swarms and afterswarms are discussed.
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  • 11
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Chez les Guêpes et les Frelons, les cellules sont hexagonales lorsqu'elles sont situées dans les zones centrales du rayon. Les cellules périphériques, comme toutes les cellules au début de leur construction, ont des parois arrondies plutôt que angulaires. La transformation d'une cellule en forme de gobelet, à parois arrondies, en une cellule hexagonale avec un angle de 120° entre les parois est partiellement due à des processus de transformation des parois cellulaires existantes au moment où de nouvelles parois leur sont attachées depuis le côté extérieur. Le développement de la construction des cellules initiales aboutit à 6 parois dans les rayons construits autour d'une seule cellule centrale ou à 5,5 parois lorsqui'il y a 2 cellules centrales contiguës. Cependant, dans les constructions ultérieures, ce type d'évolution des parois diminue graduellement à mesure que de nouveaux anneaux de cellules sont ajoutés, pour atteindre une valeur moyenne de 3 nouvelles parois par cellule, indépendamment du fait que le rayon s'est construit autour d'une ou de deux cellules centrales. Les résultats présentés dans cet article sur l'utilisation plus efficiente des parois dans les rayons plus grands apportent une confirmation du caractère économique de l'utilisation des matériaux dans la construction du rayon par les Vespinæ.
    Notes: Summary The individual cell in the hornet or wasp comb is hexagonal in cross-section when it is one of the inner “ring” of cells. On the other hand, peripheral cells, like all cells built initially, have rounded rather than angled walls. This transformation from a goblet-shaped cell with rounded walls to an hexagonally-walled cell with an angle of 120° between each two walls is partly acheived by additional processing of the existing cell walls as new walls (between old and new cells) are accreted onto them from the outside. The comb cells are essentially hexagonal so that the “expenditure” in the building of the initial cell(s) is either 6 walls (in combs built around a single central cell) or 5.5 walls (where there are two abutting, central cells). With subsequent building, however, this “wall expenditure” diminishes gradually as more rings of cells are laid down, approaching an average value of 3 new walls per cell regardless of whether the comb is built around one or rather two central cells. Presented data on more efficient wall utilization in the larger combs offer further confirmation of the frugality of comb construction by Vespinæ.
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  • 12
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    Insectes sociaux 29 (1982), S. 44-66 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The typical outdoor workers of red wood ants (Formica polyctena Förster) leave the nest spontaneously, even in satiated and undisturbed colonies. It is supposed that their task is not only foraging, but also to occupy a territory. After an one-day withdrawal of sugared water, the number of typical outdoor workers staying outside the nest increases, and additional outdoor workers which normally do not leave the nest in satiated colonies take part in foraging. On the average, these worker ants are younger than typical outdoor workers. Information about the degree of hunger in an ant colony is, at least partly, transferred by means of a pheromone which acts on satiated worker ants, too. After one-day's withdrawal of sugared water, ant colonies react to offering of 1-molar sugared water with an increase in the number of ants leaving the nest. Satiated colonies do not react, nor do hungry colonies to 0,1-molar sugared water or, except slightly, to the liquid from crushed insects. Apparently the recruited ants do not differ from the additional outdoor workers characterized above. The ants are at least partly recruited by means of a pheromone, which acts independently of whether they are hungry or satiated. The contents of Dufour's gland or their main component, n-undecane, cause the worker ants to leave the nest in the same way as does the odor from an alarmed nest. Ant colonies also react with a food alarm to the offering of prey, over a distance of approximately 10 m between nest and feeding place. Since the ants usually leave the feeding place only after a long period of fighting (1–2 h) and do not return to it, the reaction of a colony to prey starts later and is weaker than the reaction to sugared water. Therefore, this behaviour is appropriate not to the capture of single prey insects, but to the utilisation of accumulations of prey.
    Notes: Zusammenfassung Die typischen Außendiensttiere der roten Waldameisen (Formica polyctena Förster) verlassen das Nest spontan, auch bei gesättigten und ungestörten Völkern. Vermutlich haben sie nicht nur die Aufgabe, Nahrung zu sammeln, sondern auch, das Nestterritorium zu besetzen. Nach einem eintägigen Entzug von Zuckerwasser steigt die Anzahl der typischen Außendiensttiere, die sich jeweils außerhalb des Nestes aufhalten, und es beteiligen sich zusätzliche Außendiensttiere am Nahrungseintrag, die bei gesättigten Völkern das Nest nicht verlassen. Diese sind im Durchschnitt jünger als die typischen Außendiensttiere. Die Information über den Hungerzustand in einem Ameisenvolk wird zumindest teilweise durch ein Pheromon übertragen, das auch auf gesättigte Arbeiterinnen wirkt. Nach einem eintägigen Entzug von Zuckerwasser reagieren Ameisenvölker auf das Angebot einer 1 molaren Zuckerlösung mit einer Steigerung in der Anzhal der auslaufenden Arbeiterinnen. Gesättigte Völker reagieren nicht, und auch hungrige Völker reagieren nicht auf 0,1 molare Zuckerlösung und nur wenig auf Flüssigkeit aus zerquetschten Insekten. Die rekrutierten Arbeiterinnen unterscheiden sich anscheinend nicht von den oben charakterisierten zusätzlichen Außendiensttieren. Die Ameisen werden zumindest teilweise mit Hilfe eines Pheromons rekrutiert, das unabhängig davon wirkt, ob sie gesättigt oder hungrig sind. Der Inhalt von Dufourdrüsen oder seine Hauptkomponente, n-Undecan, bewirken eine ebensolche Auslaufsteigerung der Arbeiterinnen wie Duftstoffe aus einem alarmierten Volk. Ameisenvölker reagieren auch auf das Angebot von Beute mit einem Nahrungsalarm, und zwar über eine Entfernung von etwa 10 m zwischen Nest und Futterplatz. Da die Arbeiterinnen den Futterplatz meistens erst nach längerem Kampf (1–2 h) verlassen und nicht zu ihm zurückkehren, beginnt ein Nahrungsalarm zu Beute später und ist schwächer ausgeprägt als ein Nahrungsalarm zu Zuckerwasser. Deshalb ist dieses Verhalten nicht dazu geeignet, einzelne Beuteinsekten zu überwältigen, sondern dazu, Ansammlungen von Beutetieren zu nutzen.
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  • 13
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    Insectes sociaux 29 (1982), S. 15-24 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume L'organisation sociale chez lesDictyna et lesMallos comprend des espèces solitaires, des espèces qui vivent en groupes et gardent des territoires (grégaires, territoriales), et une espèce vivant en groupe (Mallos gregalis) qui ne conserve pas de territoires (grégaire, non-territoriale). L'interattraction par l'intermédiaire de la soie existe chezM. gregalis et chez une espèce grégaire, territoriale (Dictyna calcurata); mais elle ne semble pas exister chez une autre espèce grégaire, territoriale (M. trivittatus) ni chez une espèce solitaire (M. niveus). Les femelles adultes deM. gregalis ont été repoussées par la soie d'autres espèces de dictynides. Toutes les espèces qui ont été testées ont été repoussées par la soie de l'araignée aranéideAraneus diadematus.
    Notes: Summary Social organization withinDictyna andMallos includes solitary species, species that live in groups and maintain territories (communal, territorial), and a group-living species (Mallos gregalis) that does not maintain territories (communal, non-territorial). Silk-mediated interattraction occurs inM. gregalis and in a communal, territorial species (Dictyna calcurata); but it does not seem to occur in another communal, territorial species (M. trivittatus), nor in a solitary species (M. niveus). Adult females ofM. gregalis were repelled by the silk of other dictynid species. All spiders that were tested were repelled by the silk of an araneid spider (Araneus diadematus).
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  • 14
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    Insectes sociaux 29 (1982), S. 86-94 
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Resume Dans le développement des ovarioles des ouvrières deFormica sanguinea, on peut distinguer huit phases qui correspondent à celles de la fourmi rousseFormica polyctena (Otto, 1958). Ces phases constituent un cycle bien défini chez des ouvrières dont l'âge est connu précisément: les tubes indifférenciés des jeunes individus montrent un nombre croissant de chambres gonflées, le maximum étant atteint vers la quatrième semaine. Une dégénération assez rapide se manifeste peu après, de sorte que la plupart des ovarioles apparaissent comme des tubes vides contenant encore quelques corps jaunes. Chez les ouvrières âgées de plus d'une année et demie, on trouve des ovarioles à des phases différentes, d'après la situation physiologique de l'ouvrière dans le nid: les fourrageuses ont toujours des ovarioles complètement dégénérées tandis que les ouvrières hivernantes peuvent posséder des ovarioles dans une phase de régression moins avançée. Le nombre d'ovarioles paraît lié à la taille: les petites ouvrières ont en moyenne deux ovarioles de chaque côté, les plus grandes de trois à cinq.
    Notes: Summary As in the red wood antFormica polyctena (Otto, 1958) the ovariole development inFormica sanguinea workers consists of eight stages well defined in time. This is revealed by investigations on workers of well known age. The undifferentiated tubes in young workers develop more and more into protuberant chambers, reaching a maximum growth around the fourth week. They then regress rather rapidly and after five weeks most ovarioles look like empty tubes containing some yellow bodies. Ovarioles of workers older than one year and a half, however, can be in various stages according to their physiological condition in the nest: foraging workers always have fully degenerated ovarioles, while the hibernating individuals still can have ovarioles in an early regression stage. The number of ovarioles seems to be related to body length: small individuals have on the average two ovarioles on each side, larger ones three to five.
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  • 15
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    Insectes sociaux 29 (1982), S. 118-123 
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  • 16
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    Description / Table of Contents: Resume Les ouvrières et les mâles deScaptotrigona postica éclosent de cellules morphologiquement identiques. Habituellement, chaque cellule ne contient qu'une seule abeille. Cependant, nos observations montrent que quelques cellules, dispersées sur le rayon à couvain, contiennent plusieurs œufs. Etant donné que les œufs supplémentaires donnent des mâles, ils ont probablement été pondus par des ouvrières nourrices, après la ponte de la reine. Bien qu'il n'y ait pas de différence morphologique entre cellules de mâles et cellules d'ouvrières, elles contiennent une quantité de nourriture significativement différente. Les mâles sont élevés dans des cellules qui contiennent moins de nourriture que celles où sont élevées les ouvrières: la différence est significative au niveau de 1 %. Ceci conduit à penser que l'ouvrière pourrait reconnaître la cellule avant de pondre et que cette reconnaissance se ferait à partir de la quantité de nourriture contenue dans la cellule.
    Notes: Summary Workers and males of the stingless beeScaptotrigona postica emerge from morphologically similar cells. Normally only one bee is reared in each brood cell, but we found that some of the cells, interspersed throughout the brood comb, contained more than one egg. Because these additional eggs produced adult males, they were probably laid by nurse bees (workers) after the queen had oviposited in the cells concerned. Although there is no morphological difference between male and worker cells a significant difference was found in the amount of food inside them. The cell where the male is reared shows less food than the worker cell, difference that is statistically significant at 1% level. This fact suggests that: the worker might recognise the cell before oviposition and that this recognition is based on the difference of food quantity.
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  • 17
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    Insectes sociaux 29 (1982), S. 164-174 
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    Topics: Biology
    Description / Table of Contents: Resume ChezLasius sakagamii, le taux de reproduction est en relation avec la densité des reines dans chaque nid. Dans les nids à forte densité de reines, le développement des ovaires et le taux de ponte de chaque reine sont plus faibles que dans les autres nids, alors que le nombre des œufs dans chaque nid est plus élevé. En général, dans les nids à très forte densité de reines (plus du 25 reines par mètre carré de nid) ou avec des faibles rapports ouvrières/reine (moins de 5 000 ouvrières pour une reine), aucune reine ailée n'est produite. C'est aussi le cas des nids où les rapports larves/ouvrière sont élevés (plus de 5 larves par ouvrière). D'autre part, la production des ouvrières et des mâles est plus grande dans les nids à forte densité de reines que dans ceux où la densité de celle-ci est faible.
    Notes: Summary The reproduction rate ofL. sakagamii is related to the queen density in each nest. In nests with higher queen densities, the ovarian development and the egg-laying rate of each queen is lower, though the number of eggs produced per nest is larger. In general, in nests with very high queen densities (more than about 25 queens per square meter of nest) or low worker/queen ratios (less than about 5,000 workers per queen), no alate queens are produced. Further, nests with high larva/worker ratios (more than about 5 larvae per worker) also produce no alate queens. On the other hand, the production of workers and males is larger in nests with high queen densities than in those with low queen densities.
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  • 18
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    Topics: Biology
    Description / Table of Contents: Summary In the antCataglyphis cursor, the parthenogenetic reproductive eggs laid by workers are bigger than the mated queens' ones. Laboratory studies about the evolution of the egg length were carried out in colonies with and without a queen. An attempt was made to estimate the number of eggs produced by each type of society. In societies with a queen, workers remain unproductive and the queen's laying is about one thousand eggs in a season; new queens and males can be yielded but many new workers are brought up. In queenless societies, workers lay a lot of eggs, breed young queens foremost, sometimes males and fewer new workers. There as no biased eggs; the nurse's physiological state sets the female larvæ toward queens or workers. In the normal turnover, the alates are born from eggs of the early season, which are the biggest ones. But small sized late eggs can also evolve into queens if the larvæ are bred by workers whose ovaries are active. That is particularly noticeable in queenless colonies where queens can be obtained from eggs laid eleven weeks after the start of oviposition.
    Notes: Resume Chez la FourmiCataglyphis cursor, les ouvrières orphelines produisent par parthénogénèse des œufs reproducteurs plus volumineux que ceux des reines fécondées. On a étudié en élevage, l'évolution de la longueur des œufs dans des sociétés avec reine et des sociétés sans reine et tenté d'estimer le nombre d'œufs produits par des colonies d'effectifs variés. Dans les sociétés avec reine, les ouvrières restent stériles dans les conditions normales et la ponte royale est d'environ un millier d'œufs dans la saison; il peut se former des jeunes reines et des mâles, mais il apparaît surtout beaucoup de nouvelles ouvrières. Dans les sociétés orphelines, les ouvrières pondent un grand nombre d'œufs, élèvent en priorité des jeunes reines, parfois des mâles et moins de nouvelles ouvrières. Il n'existe pas d'œufs préorientés. C'es l'état physiologique des ouvrières nourrices qui conditionne de devenir reine ou ouvrière des larves femelles: dans le cycle normal, les ailés sont issus des œufs du début de ponte, qui sont les plus gros; mais des œufs tardifs et de plus petite taille peuvent aussi donner des reines si les larves qui en sont issues sont élevées par des ouvrières dont l'ovaire est en activité. Cela est particulièrement évident dans les sociétés orphelines où l'on peut obtenir des reines à partir d'œufs pondus onze semaines après le début de la ponte.
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  • 19
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    Insectes sociaux 29 (1982), S. 308-331 
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    Topics: Biology
    Description / Table of Contents: Resume La fourmi migratriceNeivamyrmex nigrescens a été étudiée sur le terrain pour déterminer comment le recrutement, l'emplacement et la quantité de nourriture influencent la fréquence, la distance et la direction des émigrations. Les observations sur l'affouragement montrent que les émigrations sont habituellement précédées par des raids, se poursuivent sur une colonne de raid réussi et se terminent près des sites de raids. Cependant, le recrutement alimentaire n'est pas un préliminaire nécessaire à l'émigration, pas plus que les émigrations ne se font toujours dans un endroit où il y a beaucoup de raids. En général, le nouveau nid n'est pas construit sur un site de raids, et il y a un court délai entre la découverte d'un site de nidification et le déclenchement de l'émigration. La direction, la distance et le déroulement temporel des émigrations sont liés plus directement à la découverte des sites de nidification qu'aux sites de raids, ce qui suggère des mécanismes de recrutement distincts. Etant donné que les raids et les émigrations disparaissent lorsqu'on suralimente les colonies, ces conduites ont un facteur de motivation commun, en l'occurrence la stimulation du couvain. L'effet réciproque entre la stimulation générale issue du couvain et le recrutement à des stimulations spécifiques, suscite une utilisation efficace du temps d'activité à la surface et empêche une exposition inutile de la reine et du couvain. La tendance à émigrer dans les endroits où il y a beaucoup de raids provient de la découverte d'un nid dans un tel endroit. Ainsi une colonie suit-elle généralement sa réserve de nourriture. Cependant, les émigrations gênent beaucoup les raids et ont probablement évolué dans des conditions écologiques très différentes de celles de la présente étude.
    Notes: Summary Field studies ofNeivamyrmex nigrescens were conducted to determine how recruitment to, location and amount of food affect emigration frequency, distance and direction. Observations of foraging showed that emigrations were usually preceded by raids, proceeded over a successful raid column, and terminated near raid sites. Recruitment to food was not a necessary prelude to emigration, however, nor did emigrations always move to an area of heavy raiding. The new nest was not usually formed in a raid site, and there was a short latency from the discovery of the nest site to the onset of the emigration. Direction, distance, and timing of emigrations were related more directly to discovery of nest sites than raid sites, suggesting separate recruitment mechanisms. Because both raids and emigrations were eliminated by overfeeding of colonies, these behaviors share a common motivating factor, namely, brood stimulation. The interplay between general arousal from the brood and recruitment to specific stimuli promotes efficient use of surface activity time and prevents unnecessary exposure of queen and brood. The tendency to emigrate into areas of heavy raids results from the discovery of a nest in that area; thus a colony generally follows its food supply. Emigrations interfere considerably with raiding, however, and probably evolved under ecological conditions very different from the present study.
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  • 20
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    Description / Table of Contents: Zusammenfassung Die mandibularen Drüsen der AmeiseWasmannia auropunctata enthalten 2,5-dimethyl-3-isopentylpyrazin, eine Verbindung mit der andere gleich-artige Nestbewohner von gestorten Arbeitern herbeigelockt werden. Während einer aggressiven interspezifischen Begegnung kann die kleine Ameise das Alkylpyrazin als ein Abstossungsmittel benutzen und ihren Opponenten noch dazu mit ihrem wirkungsvollen giftigen Stich untauglich machen. Alkylpyrazine sind schon früher in Vertreten der Unterfamilien Ponerinæ, Formicinæ und Dolichoderinæ gefunden worden, jedoch ist dies der erste Bericht über Alkylpyrazine in den mandibularen Drüsen einer Art der Myrmicinæ.
    Notes: Summary Mandibular glands of the ant,Wasmannia auropunctata, contain 2,5-dimethyl-3-isopentylpyrazine, a compound which attracts nestmates to disturbed workers. During interspecific aggressive encounters, this small ant may utilize the alkylpyrazine as a repellent as well as disabling opponents with its potent sting venom. Alkylpyrazines have been previously identified as cephalic products from ants of the subfamilies Ponerinæ, Formicinæ, and Dolichoderinæ but this is the first report of an alkylpyrazine from the mandibular glands of a member of the Myrmicinæ.
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  • 21
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    Insectes sociaux 29 (1982), S. 383-401 
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    Topics: Biology
    Description / Table of Contents: Summary For two colonies ofPolistes reared in close proximity to one another, a series of physiological and ethological indices was determined for all of the female offspring surviving until mid-july. The indices chosen concern physiological parameters related to ovarian function, and ethological parameters expressing forms of integration into colony life. Multivariate analysis leads to the recognition of a number of clusters which fall into two functional groups: one is oriented towards the function of laying eggs and the other towards the function of maintenance of the colony. In spite of the obvious analogy, these two groups do not coincide perfectly with the two castes conventionally distinguished in the female sex; their divergence results from a succession of factors implicating both the state of belonging to a caste of the different individuals, and the direct causal factors the exact nature of which remains to be stated precisely.
    Notes: Resume Dans deux guêpiers dePolistes, placés au voisinage l'un de l'autre, on relève une série d'indices physiologiques et éthologiques sur l'ensemble des descendantes encore vivantes à la mi-juillet; les indices choisis concernent des paramètres physiologiques liés à la fonction ovarienne et des paramètres éthologiques exprimant des formes d'intégration à la vie de la colonie. L'analyse factorielle conduit à discerner un certain nombre de sous-populations, que l'on peut regrouper en deux grandes séries dont on propose une interprétation fonctionnelle: l'une s'orientant vers la fonction de ponte et l'autre vers la fonction d'entretien de la colonie. Malgré une analogie évidente, ces deux séries ne coïncident pas parfaitement avec les deux castes classiquement discernées dans le sexe femelle; leur divergence résulte d'une série de facteurs impliquant à la fois l'appartenance de caste des divers individus et des facteurs causaux immédiats dont la nature exacte reste à préciser.
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  • 22
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    Description / Table of Contents: Resume Nous avons réalisé une étude expérimentale du développement de grandes larves ayant hiverné, chez 4 espèces deMyrmica. Utilisant une gamme de températures de 15°C à 25°C, nous avons montré que: 1. Il n'y a pas de différences entre les espèces quant à l'effet de la température sur les durées de développement. Toutes suivent le modèle: log. durée de développement =a-b T°C, avec la même valeur pour b. Ceci donne un Q10 effectif d'environ 3,1. Ce résultat est en accord avec les estimations de respirométrie chez les ouvrières de fourmis. 2. Les valeurs de a diffèrent de façon significative entre la plupart des espèces, ce qui confirme la différence intrinsèque que nous avions démontrée à la température constante de 22,5°C dans un précédent travail. Les durées de développement larvaire peuvent être ainsi classées, de la plus rapide à la plus lente:Myrmica ruginodis Nyl.,Myrmica rubra L.,Myrmica scabrinodis Nyl. etMyrmica sabuleti Meinert. A toutes les températures, il faut 1,5 fois plus de temps àM. sabuleti qu'àM. ruginodis pour qu'une grande larve ayant hiverné se transforme en nymphe blanche. 3. Nous n'avons pas observé de grandes différences dans la survie des larves et la production des reines, aux températures utilisées dans nos expériences. La plupart des espèces survivent le mieux à 22°C environ. 4. Les résultats sont brièvement discutés en fonction de la distribution écologique des 4 espèces dans le Sud de l'Angleterre. 5. Nous discutons les effets possibles d'un régime de température variable. Nous suggérons que l'amplitude des variations peut ne pas avoir un effet important alors que la périodicité des variations pourrait avoir un effet plus important.
    Notes: Summary The effect of temperature upon the development of large hibernated larvaæ of fourMyrmica species has been tested experimentally. Over the viable temperature range of 15–25°C, it was found that: 1. There are no differences between the species in the effect of temperature upon development times. All fit the model log Dev. time=a-b T°C with a common value for b. This gives an effective Q10 of about 3.1 which agrees with respirometrical estimates for worker ants. 2. The value for the intercept (a) differs significantly between most species confirming the intrinsic difference that has been demonstrated at a constant 22.5°C in previous work. The development times of larvæ can be ordered from fastest to slowest being:Myrmica ruginodis Nyl.,Myrmica rubra L.,Myrmica scabrinodis Nyl. andMyrmica sabuleti Meinert. At any temperature it takesM. sabuleti about 1.5 times as long asM. ruginodis to grow from a large hibernated larva to a white pupa. 3. No large differences in larval survival or gyne production could be detected between the temperature treatments. There was an indication that most species, survived best at about 22°C. 4. The results are discussed briefly in terms of the ecological distribution of the four species in the South of England. 5. The possible effects of a fluctuating temperature regime are discussed, it is suggested that the amplitude of fluctuations may not have any great effect whereas the periodicity could be more important.
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    Insectes sociaux 30 (1983), S. 149-164 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Chromosomenzahlen von 40 Ameisenarten werden mitgeteilt. Für 22 Arten wird zusätzlich der Karyotyp vorgelegt. Die haploiden Chromosomenzahlen bewegen sich zwischen n=8 und n=26. Bemerkenswert sind die Karyotypen der GattungLasius. Diese Karyotypen besitzen, abgesehen von einem oder zwei mediozentrischen Paaren, ausschliesslich acrozentrische Chromosomen. Alle übrigen Karyotypen bestehen überwiegend aus medio- bzw. submediozentrischen Chromosomen. In der GattungCamponotus entspricht die Gruppierung in Untergattungen auch einer Gruppierung von unterschiedlichen Chromosomenzahlen. Für die GattungenAphœnogaster undLeptothorax gilt diese Entsprechung nicht.
    Notes: Summary The chromosome numbers of 40 ant species are reported. For 22 species the karyotypes as well as the chromosome numbers are presented. The chromosome numbers range between n=8 and n=26. Remarkable karyotypes are those of the genusLasius in exhibiting mainly acrocentric chromosomes. In all other karyotypes the majority of chromosomes show medio- or submediocentric centromere position. Differences in chromosome numbers in the genusCamponotus reflect the grouping in subgenera with the exception ofTanœmyrmex. This pattern is not true for the generaAphœnogaster andLeptothorax, where a variety of chromosome numbers were found in the different subgenera.
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  • 24
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    Insectes sociaux 30 (1983), S. 210-220 
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    Topics: Biology
    Description / Table of Contents: Summary Density effects inEublaberus distanti have been tested upon larvæ in groups of 20, 100 and 500 individuals. Increased density leads to higher larval mortality, particularly in young larvæ, a larger difference between slow development and rapid development, and a decrease in adult size. Density effects in cockroaches can be explained in terms of population dynamics comparable to phasic modifications of desert Locusts.
    Notes: Resume Les effets de la densité ont été testés sur des lots de larves de l'espèceEublaberus distanti, lots de 20, 100 et 500 individus par 615 cm2. Lorsque la densité augmente, la mortalité larvaire s'accroit, surtout chez les larves jeunes. L'augmentation de densité accentue les différences entre individus à développement rapide et développement plus lent, de même qu'elle implique une réduction de taille chez les adultes. Les effets de la densité s'expliquent par la dynamique de la régulation des populations de Blattes, comparable aux modifications phasaires des Acridiens migrateurs.
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    Insectes sociaux 30 (1983), S. 235-240 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Ein Volk vonHarpagoxenus sublœvis wurde in einem naturnahen Habitat künstlich angesiedelt. Am 7. und 8. Juli 1981, zwischen 2015 und 2130 MEZ, konnte erstmalig unter Freilandbedingungen das Locksterzelverhalten ergatomorpher Jungweibchen in Nestnähe beobachtet werden. Gleichzeitig fand am 7. Juli ein Sklavenraubzug desHarpagoxenus-Volkes auf ein benachbartesLeptothorax acervorum (Fabricius)-Nest statt. Das bisher nur aus Laborbeobachtungen bekannte Sexualverhalten wird somit unter Freilandbedingungen in gleicher Form gezeigt.
    Notes: Summary A colony ofHarpagoxenus sublœvis was artificially established in a near-natural habitat. The sexual calling behavior of young ergatomorphic queens was observed for the first time under field conditions on July 7 and 8 1981, between 2015 and 2130 Central European Time. Simultaneously, on July 7, theHarpagoxenus colony conducted a slave raid on a neighboring nest ofLeptothorax acervorum (Fabricius). Previously the sexual behavior was known only from laboratory studies, these observations now show that it is performed in an identical manner under natural conditions.
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    Insectes sociaux 30 (1983), S. 255-258 
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    Topics: Biology
    Description / Table of Contents: Summary The author proposes a new method of marking (with wire rings) which renders possible the individual identification of all the members of the colony.
    Notes: Resume L'auteur propose une nouvelle méthode de marquage, au moyen de ceintures de métal, permettant d'identifier chaque membre de la société.
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  • 27
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    Topics: Biology
    Description / Table of Contents: Summary In the antCataglyphis cursor, four categories of workers can be defined: minim, small, medium, large and very large. In each category, the workers are able to lay reproductive eggs and to produce, by parthenogenesis, queens, males and new workers of all sizes. Medium sized workers show the higher productivity. Average egg size and fecundity are related to workers size. All eggs seem able to develop. Difference between workers appear more quantitative than qualitative; the monophasic polymorphism of this species corresponds to this biological resemblance.
    Notes: Resume Chez la fourmiCataglyphis cursor, on peut définir 4 catégories d'ouvrières: minimes, petites, moyennes, grandes et très grandes. Dans chaque catégorie, les ouvrières sont capables de pondre et de produire par parthénogenèse, des reines, des mâles et de nouvelles ouvrières de toutes tailles. Les ouvrières moyennes présentent la plus forte productivité. La grosseur moyenne des œufs et la fécondité varient avec la taille des ouvrières; tous les œufs semblent capables de se développer. Les différences entre ouvrières apparaissent donc davantage comme quantitatives que qualitatives; le polymorphisme monophasique de l'espèce correspond bien à cette similitude biologique.
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    Insectes sociaux 31 (1984), S. 51-73 
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    Topics: Biology
    Description / Table of Contents: Summary Seed harvesting by the antMessor galla has been followed over a 2.5-year period in a woodland savanna of the sahelo soudanian zone, where seeds are produced only once a year, in restricted and fluctuating numbers following a short rainy season. Ants harvesting was highly seasonal. At the onset of the dry season, when new seeds were available, the ants harvested very intensively and exhibited a clear choice of some seeds they stored in their underground granaries. Their activity decreased there-after and remained low and irregular: the ants mainly collected the most abundant seed species found in their nest vicinity. The yearly total collected ranged between 3.105 and 4.106 seeds for each colony studied (1 to 19 kg in fresh weight). In an area studied more precisely in 1978–79, 1979–80 and 1980–81, the ants harvesting amounted to 4, 5 and 4 kg ha−1 yr−1, which represented respectively 0.4, 1.7 and 0.5% of the annual herbaceous seed production. In 1978–79, 3 studied colonies did not seem to have stored in their nest more than one annual harvest. Ants harvesting varied in space and in time, according to the available resources around their nests. This adaptibility is considered to be an effective adjustment to a fluctuating food supply.
    Notes: Resume La récolte des fourmis granivoresMessor galla a été suivie pendant deux ans et demi, dans un milieu sahélo-soudanien où les graines sont produites une fois par an, à l'issue d'une courte saison des pluies, en quantités limitées et variables selon les années. La récolte des fourmis est très saisonnière. En début de saison sèche, lorsque les nouvelles graines de l'année arrivent à maturité, les fourmilières récoltent intensément et montrent une nette préférence pour certaines graines qu'elles mettent en réserve. Leur activité décroît ensuite et reste faible et irrégulière tout le reste de l'année; elles ramènent alors essentiellement les graines les plus abondantes du milieu environnant leur nid. Les récoltes annuelles des fourmilières étudiées ont varié, selon la taille des colonies, de 3×105 à 4×106 graines, et de 1 à 19 kg. Dans un quadrat suivi plus précisément, les fourmis ont récolté successivement chaque année en 1978–80, 1979–80 et 1980–81, 4, 5, puis 4 kg/ha de graines, ce qui a représenté 0,4, 1,7, puis 0,5% de la production annuelle de graines par la végétation herbacée. En 1978–79, 3 colonies étudiées ne semblaient pas avoir stocké dans leurs nids plus d'une année de récolte. La récolte des fourmis a varié dans le temps et dans l'espace en fonction des disponibilités du milieu entourant leur nid. Cette plasticité semble être une réponse adaptée à la variabilité saisonnière et interannuelle des disponibilités alimentaires.
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    Insectes sociaux 31 (1984), S. 74-86 
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Resume Cette étude faite sur le terrain dans le désert du sud-ouest des Etats-Unis différencie le comportement social de cinq espèces de fourmis moissonneuses:Pogonomyrmex barbatus, P. rugosus, P. maricopa, P. desertorum, P. californicus. Les espèces diffèrent significativement quant à leurs rythmes d'activité pour plusieurs tâches (fourragement, maintien du nid, surveillance, maintien des débris, rassemblement), ainsi que pour l'utilisation de l'espace autour du nid et la réaction de la societé à un dérangement. En général, les différences de comportement peuvent s'organiser en fonction de la quantité habituelle d'ouvrières hors du nid. Chez les espèces ayant une plus grande quantité d'ouvrières à l'extérieur du nid, l'organisation de la société met plus en valeur l'acquisition de la nourriture et la territorialité. Par contre, les espèces ayant moins d'ouvrières hors du nid ont un comportement social qui leur permet de réduire leur contact avec d'autres sociétés. En examinant les régularités temporelles et spatiales du comportment social, on peut mieux comprendre les rapports interspécifiques chez les communautés de fourmis.
    Notes: Summary This field study examines the social behavior of five sympatric species of desert seed-eating ants (Pogonomyrmex barbatus, P. rugosus, P. maricopa, P. desertorum, P. californicus). The species differed significantly in measures of activity rhythms in various colony tasks, use of space around the nest yard, and reaction to disturbance. Species differences were related to the typical size of a colony's outside work force. The behavior ofP. rugosus, P. barbatus, andP. maricopa, which had larger outside work forces, emphasized territoriality and the acquisition of food; that ofP. desertorum andP. californicus, which had smaller outside work forces, emphasized the avoidance of contact with other colonies. Examining the patterns in colony behavior can illuminate interspecific relationships in desert ant communities.
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    Insectes sociaux 30 (1983), S. 57-69 
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Resume Les reines du frelon oriental sont agressives l'une envers l'autre au début de la saison active, pendant les mois de mai, juin et juillet: elles défendent leur “Lebenraum” à l'intérieur du nid et ne permettent à aucune autre reine de pénétrer dans leur territoire. A cette période, toute rencontre de 2 reines, dans le nid de l'une ou dans tout autre endroit, déclenche un comportement agressif mutuel. Le combat qui s'ensuit peut durer des heures et dans son déroulement, si l'une des reines défait l'autre elle la pique au cou jusqu'à la mort. Cependant, dans de nombreux exemples, le combat n'apporte pas de solution: les combattants épuisés se retirent avant de reprendre le combat. D'autres fois, l'une des reines peut réussir à mutiler sa rivale en amputant l'extrémité de ses pattes. La reine estropiée abandonne le combat en adoptant une posture d' “infériorité” à l'égard du vainqueur et en offrant de la nourriture. Nous avons décrit en détail les différentes phases du combat entre les reines mises par deux.
    Notes: Summary Queens of the Oriental hornet are aggressive towards one another in the beginning of the active season, during the months of May, June and July: they defend their “Lebenraum” within the nest and do not enable any other queen to enter their territory. At that period any encounter between two queens, whether within the nest of the one or anawhere else, releases mutual aggressive behavior. The ensuing combat may last for hours and in its course, if the one queen beats the other, it stings it to death in the neck. In many instances, however, the combat remains unresolved and the exhausted combatants withdraw to recuperate before resuming their battle. At other times, one of the queens may succeed in maiming its rival by amputating the tips of its limbs at which point the disabled queen concedes the fight by assuming an “inferior” posture towards the victor and making a food offering. The various phases in the combat between queen pairs are described in detail.
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    Description / Table of Contents: Resume Les distributions de trois «formes», en réalité des espèces jumelles d'Iridomyrmex purpureus furent étudiées près de Morgan en Australie du Sud, où la précipitation annuelle est de 230 mm. La dispersion des colonies a été décrite en détail pour une «forme bleue» et pour la formepurpureus sens. strict. qui existait dans cette région bien au-delà de ses limites pour les basses précipitations. Une colonie exceptionnellement grande d'I. purpureus couvrait un territoire de 10 ha: comprenant plus de 85 nids, elle avait plus de 1 500 entrées individuelles. Nous avons décrit les interactions entre les ouvrières des différentes formes, et leurs interactions au sein et entre les colonies de la même forme. La totalité de la faune de fourmis de la région et les faunes qui accompagnaient les différentes espèces d'Iridomyrmex furent étudiées au moyen de récoltes faites à la main et de piègeages dans des fosses. La diversité (abondance d'espèces) et la présence d'espèces de fourmis sans adaptations particulières sont liées au type de végétation et auxIridomyrmex associées. Les prises dans les pièges suggérant que le nombre d'individus et le nombre d'espèces d'autres taxons actifs à la surface du sol, en particulier les collemboles, sont affectés par le nombre de fourmis, en particulier les espèces d'Iridomyrmex et d'autres fourmis sans adaptations particulières. Au niveau évolutif, lesIridomyrmex influencent aussi la faune associé. On a noté la présence d'araignées zodariides présentant un mimétisme de couleur par rapport aux espèces presque identiques d'I. purpureus, dont ils sont des prédateurs. Nous avons noté et discuté des cas possibles de mimétisme d'I. purpureus par des fourmis du genreCamponotus.
    Notes: Summary The distributions of three “forms”, actually sibling species, of meat ant were studied near Morgan, South Australia, an area with mean annual rainfall of 230 mm. Colony dispersion is described for a “blue form” and for formpurpureus sens. strict. which occurs in this locality far beyond its normal low rainfall limit. An unusually large colony ofpurpureus had a territory covering 10 ha with more than 85 nests and over 1,500 individual nest entrances. Worker interactions between forms, and within and between colonies within forms are described. The ant fauna of the locality as a whole and the faunas accompanying differentIridomyrmex species were investigated by means of hand collections and pitfall trapping. Diversity (species — richness) and the occurrence of widely adapted ant species are related to vegetation type and associatedIridomymex. Catches of pitfall traps suggested that the numbers of individuals and species of other taxa active on the soil surface, predominantly Collembola, were affected by numbers of ants, particularlyIridomyrmex species and other, widely adapted ants.Iridomyrmex also influence associated fauna at an evolutionary level. The presence of zodariid spiders which are sibling species-specific colour mimics and predators of meat ants is noted. Possible cases of mimicry of meat ants by ants of the genusCamponotus are recorded and discussed.
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    Insectes sociaux 31 (1984), S. 103-111 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Neständerungen der Weibchen einer neotropischen Faltenwespe,Polìstes versicolor, wurde in Panama beobachtet. In erstem Falle wurden häufige Lageänderungen zwischen zwei benachbarten Nestern beobachtet. Einmal wechselte ein ovariell höchstentwickeltes Weibchen häufig die Nester. In zweitem Falle, verliessen vielleicht alle Weibchen desselben Nestes und wurden von einem naheliegenden Neste aufgenommen. In letztem Falle, wurden einige Arbeiterinnen eines Nestes angenommen von einem anderen Nest, deren Gründerinnen wahrscheinlich nicht ihre nahe Verwandten waren. Die Verhalten bei Umnestung wurden beschrieben.
    Notes: Summary Shifts of females ofPolistes versicolor between adjacent nests were observed in Panama. In the first case, females of two neighboring nests frequently changed their positions and one female who had developed eggs in ovaries shifted between the nests repeatedly. In the second case, possibly all females shifted to a nearby nest after abandonment of their original nest and were accepted by females of the new nest. In the third case where workers shifted, relatedness between them and foundresses of the new nest was considered to be low. Behaviours accompanying the shifts are described.
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    Description / Table of Contents: Resume Nous avons étudié le cycle biologique de la fourmi myrmicinePristomyrmex pungens. En général, les colonies de cette espèce se composent de plusieurs milliers de petites ouvirères, tandis qu'un petit nombre de mâles (2–3 %) apparaissent occasionnellement en juin et juillet dans les colonies mûres et que de grandes ouvrières à ocelles et spermathèque abortive (reines ergatoïdes) ont pu être observées très rarement. Nous avons démontré que les petites ouvrières vierges peuvent pondre des œufs qui donnent d'autres petites ouvrières. Les cellules des ganglions cérébroïdes et les ovogonies des ouvrières sont diploïdes (2 n=24), mais la formule haploïde (n=12) a pu être observée chez les ovocytes au stade pachytène ainsi que chez les spermatocytes des mâles. Ces mâles possèdent des organes copulatoires normaux et leur spermatogenèse est normale, mais ils ne fécondent probablement pas les petites ouvrières, lesquelles sont dépourvues de spermathèque et d'organes copulatoires fonctionnels. Ces observations indiquent que la reproduction chezP. pungens est assumée de façon prépondérante, et probablement complètement, par les petites ouvrières, de façon par conséquent thélytoque. Nous discutons l'évolution du cycle biologique deP. pungens, en soulignant la difficulté d'appliquer à cette espèce le concept de “reine” ou même de décider si elle est »eusociale» ou non. Au regard de l'isolement génétique présumé entre colonies, le mode de sélection maintenant dans ce cas une structure sociale est probablement davantage une sélection de groupe interdémique plutôt qu'une sélection de parentèle.
    Notes: Summary The life cycle of the myrmicine antPristomyrmex pungens was investigated. Colonies of this species are usually composed of several thousand small workers, although a few males (2–3 %) occasionally appear during June and July in mature colonies, and large workers with ocelli and abortive spermathecae (here termedergatoid queens) were observed extremely rarely. We found that the virgin small workers can lay eggs and that these develop into further small workers. Cerebral ganglion cells and oogonial cells had the diploid chromosome number (2 n=24), but the haploid number (n=12) was observed in oocytes at pachytene, and also in spermatocytes from the rare males. Males have functionally normal copulatory organs and their spermatogenesis is normal, but they probably do not mate, because small workers have no spermatheca and their copulatory organs are degenerative. These observations indicate that reproduction inP. pungens is carried out predominatly or, probably, wholly by the small workers and hence is thelytokous. We discuss the evolution of theP. pungens life cycle, pointing out the difficulty of applying the “queen” concept to this species or even in deciding whether or not it is “eusocial”. In view of the apparent genetic isolation between colonies, the mode of selection maintaining sociality in this case is probably interdemic group selection rather than kin selection.
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    Description / Table of Contents: Summary In investigating the antennal positions and movements associated with the transfer of substance from one worker ant to another, during trophallactic contacts, the question arises as to whether these different positions and movements act as particular singals. InCamponotus vagus, these behavioural units are organized into sequences. There is no stereotypy in the sequences: recordings show great variability, particularly in the donor ant. On the other hand, differences in the organization of sequences and in their variability were seen to be related to the worker's social function (forager or broodtender worker). Trophallactic behaviour in the two partners was analysed using different methods (slow motion film with frame by frame analysis; use of radioelements with simultaneous recording of trophallactic flux and antennal movements; cross-correlogrammes). No definite system of signals and responses corresponding to antennal movements was found to underly the ant's trophallactic behaviour. But it does not exclude that the antennæ activity as a whole, owing to its structure may have a function in communication.
    Notes: Resume L'étude des positions et mouvements d'antennes qui accompagnent les transferts de substances d'une ouvrière de Fourmi à l'autre, au cours des contacts trophallactiques, pose le problème de la valeur de signal de ces différents actes. ChezCamponotus vagus, ces unités comportementales sont organisées de manière séquentielle. Il n'y a pas stéréotypie des séquences; on enregistre une grande variablité, en particulier chez l'ouvrière donneuse. D'autre part, il apparaît des différences dans l'organisation des séquences et leur variabilité, en relation avec la fonction sociale exercée par l'ouvrière (récolteuse ou nourrice). L'analyse du comportement trophallactique des deux partenaires, par plusieurs méthodes différentes (cinéma accéléré avec analyse image par image, emploi des radio-éléments avec enregistrement simultané des actes et du flux trophallactique, cross-corrélogrammes), a permis de montrer que leurs actes ne constituent pas, au niveau antennaire, un système précis de signaux et de réponses. Ceci n'exclut pas la possibilité que l'activité antennaire globale ait par sa structure une fonction de communication.
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    Insectes sociaux 31 (1984), S. 132-141 
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    Topics: Biology
    Description / Table of Contents: Resume Pour chacune des trois espèces de fourmis de la famille Dolichoderinæ, quatre modèles de reproduction des colonies ont été examinés par électrophorèse: (1) chaque colonie provient d'une seule femelle inséminée une seule fois, (2) chaque colonie provient d'une seule femelle inséminée deux fois, (3) les colonies proviennent de deux reines «égales», chacune inséminée une seule fois, et (4) les colonies proviennent de trois reines «égales», chacune inséminée une seule fois. Pour chacun de ces modèles, la fréquence des colonies de chaque composition génétique a été calculée et comparée avec la distribution observée. Les colonies étudiées deConomyrma insana sont de type monogyne. Un grand nombre des colonies étudiées deConomyrma bicolor sont de type polygyne fonctionnelle. La polygynie se trouve dans toutes les localités examinées. Peut-être la polygynie se trouve-t-elle aussi chezIridomyrmex pruinosum. Sa fréquence est peut-être moins grande que chezC. bicolor.
    Notes: Summary For each of three species of dolichoderine ants, four mating system models were tested electrophoretically. The models tested were: (1) each colony is derived from one, singly-inseminated female, (2) each colony is derived from one female, inseminated twice, (3) colonies have two, coequal, singly-inseminated queens, and (4) colonies have three, coequal, singly-inseminated queens. From each of these models, expected frequencies of colonies of various genotypic compositions were calculated. Goodness of fit of actual colony types were then tested. Conomyrma insana colonies were shown to be monogynous. A large number of theConomyrma bicolor colonies studied are functionally polygynous. Polygyny occurs in all localities examined. Polygyny may also occur inIridomyrmex pruinosum. Its occurence may be less widespread than inC. bicolor.
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    Description / Table of Contents: Summary The characteritics of tandem running were analysed in two species of Ponerine ants from tropical Africa, together with the stimuli causing either the leader or the follower to start or to maintain the tandem running. With regard to the genusMesoponera, tandem running allows the recruitment for the capture of a mobile and voluminous prey, the collective transport of a dead insect untransportable by a sole individual, the hunting of small preys and the collection of sugared substances. The genusHypoponera makes use of tandem running to recruit but only in the instance of dismembering of large prey. On the other hand it was shown that in one of the species (Hypoponera sp.), the number of tandems formed can depend on various olfactory stimuli perceived in the nearby environment of the colony. A change in certain elements of the environment can therefore cause specific effects in some of the complex interactions observed in ant societies.
    Notes: Resume J'ai analysé, chez deux espèces de Fourmis Ponérines d'Afrique tropicale, les caractéristiques de la marche en tandem et les stimuli qui interviennent, agissant sur l'ouvrièreguide ou sur l'ouvrière recrutée, pour déterminer la mise en route ou le maintien des tandems. Pour le genreMesoponera, les tandems permettent le recrutement pour la capture d'une proie mobile et volumineuse, mais aussi pour le transport collectif d'un insecte mort qui ne peut être transporté par une seule ouvrière, — ou pour la chasse d'un grand nombre de petites proies, enfin pour la récolte d'une substance sucrée. Le genreHypoponera utilise le tandem pour recruter, mais uniquement lors du dépeçage d'une proie volumineuse. D'autre part, j'ai montré que chezHypoponera sp. le nombre de tandems peut dépendre de stimuli olfactifs déterminés, perçus dans le très proche environnement de la société. Par conséquent, la modification de certains éléments de l'environnement peut avoir une action spécifique sur la manifestation d'interactions complexes observées dans les sociétés de Fourmis.
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    Insectes sociaux 31 (1984), S. 335-340 
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    Topics: Biology
    Description / Table of Contents: Resume Les réponses variées à l'humidité relative chez quatre espèces de fourmis de feu qui se trouvent au Texas (Solenopsis aurea, S. geminata, S. invicta, etS. xyloni) ont été examinées avec une chambre gradient linéaire. Seuls les ouvriers n'ont pas montré de réponse hydrokinétique, tandis que les ouvrières soigneuses de toutes les espèces examinées ont montré une préférence marquée (hydrokinesis négative) pour les atmosphères saturées (près de 100 % d'humidité relative). Les réponses sont probablement causées par la sensibilité plus élevée de la couvée à la dessication.
    Notes: Summary The responses of the four fire ant species found in Texas (Solenopsis aurea Wheeler,Solenopsis geminata Fabricius,Solenopsis invicta Buren, andSolenopsis xyloni McCook) to varied relative humidities were examined. Humidity preferences of worker ants were determined with a linear gradient chamber. Workers alone did not exhibit any hydrokinetic responses, whereas brood tending workers of all species tested showed a marked preference (negative hydrokinesis) for saturated atmospheres (near 100 % RH). The responses are presumably due to the broods' hogher susceptibility to desiccation.
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    Notes: Summary Because social parasites are relatively rare in tropical ant faunas, new or poorly known forms deserve special attention. TwoPheidole species evidently parasitic onP. indica are here described as new species from India (P. lanuginosa, P. parasitica), while a previously known northern South American form,P. microgyna Wheeler, is redescribed and evaluated as a possible parasite ofP. minutula or a closely related host species. Next, all of the nine certain or likely social parasites ofPheidole known worldwide are compared, and an anatomical parasitic syndrome is identified through character state analysis. The nine species appear to be independently evolved. The parasitic character states have tended to evolve within each of these species at different rates, and hence the evolution is interpreted as having been not only parallel among species but mosaic in nature within species (seetable I). In spite of the lesser irregularities in this pattern, an overall trend is evident: the first changes to occur were loss of the worker caste (a loss still incomplete in the overall slightly modifiedP. inquilina), reduction of size, lengthening of the scape, reduction of sculpturing on the body surface, and broadening of the postpetiole. These shifts were followed by reduction of the mandibles and the segments of the funiculus. The generaAnergatides andBruchomyrma, each based on a single extremely advanced species, are placed in synonymy underPheidole. The problematic generaHagioxenus, Parapheidole, andSifolinia are compared withPheidole and their status evaluated. The greater known diversity of parasitic ants in the temperate zones, as compared with the tropics, remains a key problem in the study of ant evolution. Whether the difference is genuine or an artifact of differential sampling cannot be determined until more intensive collecting is undertaken in the tropics.
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    Insectes sociaux 31 (1984), S. 387-402 
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    Topics: Biology
    Description / Table of Contents: Summary A detailed investigation of polyethism was carried out on a colony ofNeoponera (=Pachycondyla sensuBrown, 1973) obscuricornis, involving behavioural observations on its inhabitants, and subsequent dissection of each. Ovariant development in each ant was closely related to its social status. Ovaries are well developed among nuress and totally degenerate in foragers. This is the case in both gynes and workers, and ovarian polymorphism between the two castes is only weakly marked. The evolutionary implications of the observed relationships between nursing behaviour and reproductive ability are discussed.
    Notes: Resume L'étude détaillée du polyéthisme par l'observation des activités individuelles dans une société deNeoponera (=Pachycondyla sensuBrown, 1973)obscuricornis a été suivie de la dissection de tous les individus. L'état ovarien de chaque fourmi est en relation avec son statut social dans la colonie: développé chez les sogneuses, l'ovaire a complètement régressé chez les fourrageuses. Ce phénomène s'observe aussi bien chez les femelles que chez les ouvrières, seul un faible polymorphisme ovarient permettant de distinguer les deux castes. Les implications évolutives d'une liaison entre les conduites parentales et l'aptitude à la ponte sont discutées.
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    Insectes sociaux 31 (1984), S. 375-386 
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    Topics: Biology
    Description / Table of Contents: Resume Les relations génétiques de huit espèces de guêpes d'Europe du nord, représentantVespula s. str. (le grouperufa),Paravespula (le groupevulgaris) etDolichovespula, sont étudiées ici par électrophorèse enzymatique. Le niveau de variation génétique intraspécifique observé est relativement bas, et les populations du sud de la Finlande ne montrent pas de différences géographiques nettes. Les caractères d'allozymes sont ensuite utilisés pour construire des arbres phylogénétiques par quatre techniques de construction. Il est suggéré queDolichovespula media n'est pas étroitement apparentée aux autres espèces deDolichovespula européens, et queParavespula etVespula s. str. ne forment peut-être pas un seul groupe monophylétique. Deux des espèces étudiées,V. austriaca etD. omissa, sont des parasites sociaux obligatoires. Dans les deux cas le parasite est apparenté à son hôte. Cela appuie l'hypothèse que le parasite social apparaît généralement à partir de la même souche ancestrale que l'espèce hôte.
    Notes: Summary Genetic relationships of eight northern European yellowjacket species, representingVespula s. str. (therufa group),Paravespula thevulgaris group) andDolichovespula, are here studied by enzyme electrophoresis. The observed level of intraspecific genic variation is relatively low, and the southern Finnish populations show no clear-cut geographic differences. The allozyme characters are further used to construct phylogenetic trees by four tree-building techniques. It is suggested thatDolichovespula media is not phylogenetically closely related to other EuropeanDolichovespula species, and thatParavespula andVespula s. str. may not form a single monophyletic group. Two of the species studied,V. austriaca andD. omissa, are obligatory social parasites. In both cases the parasite is related to its host. This supports the hypothesis that the social parasite generally arises from the same ancestral stock as the host species.
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    Insectes sociaux 31 (1984), S. 361-374 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Im staate New York sind Kolonien gemischter Arten vonPolyergus lucidus undFormica schaufussi untersucht worden. Am späten Nachmittag, nach dem Höhepunkt der Tagestemperatur, wurden Sklavenraubzuge ausgeführt. Mehrfache Raubzüge auf verschiedene Kolonien vonFormica gerichtet waren normal. Dazu gehöten auch wiederholte Raubzüge auf dieselbe Kolonie. In den Laboratoriumnestern wurden etwa 75% des geraubtenFormica Gebrüts gefressen. Aus einer Gruppe von 27 Raubzüge die im Laboratorium stattfanden, wurden 25 aufFormica Nester ausgeführt die am Tage des Überfalles erkundschaftet worden waren.Polyergus Kundschafter gehören zur den ältesten Individuen der Kolonie; frischgeschlüpfte Erwachsene beteiligen sich nicht an Erkundungen während ihrer ganzen Schlüpfungssaison. Die Zusammensetzung der Gruppe vonPolyergus Arbeitern die unmittelbar vor dem Überfall auf der Oberfläche in der Nähe des Nestes umhergehen, wechselt sich kontinuierlich. Die verhaltensänderung die am häufigsten auftrat war die vom Herumgehen an einem Tag zum Kudschaften am nächsten Tag. Die zweithäufigste Änderung war die vom Kundschaften zum Herumstreifen. Das erste kundschaften der frühlingssaison fand nur einen Tag nach Erscheinung derPolyergus Larven staat. Der erste Sklavenraubzug wurde dann 4 Tage später ausgefuhrt.Formica Gebrüt war in frielebenden Kolonien bis zu 4 Wochen früher anwesend alsPolyergus Gebrüt in gemischten Nestern. ObwohlPolyergus Arbeiter gewöhnlich durch Erbrechen des Speisebreies vonFormica gefüttert werden, tranken und frassen sie gelegentlich auch Eier unabhängig vonFormica. DiePolyergus Köningen war immer nur vonFormica Arbeiter umgeben.Polyergus Eier kriechen in etwa 12 Tagen zu Larven aus, worauf das Larvenstadium noch 9 bis 12 Tagen dauert. Schlüpfung der Erwachsenen fand 20 bis 23 Tage nach dem Puppenstadium statt. FrischbefruchtetePolyergus Königinnen folgen Sklavenraubzüge und versuchen von den überfallen Nesten adoptiert zu werden indem sie die Verwirrung derFormica während eines Überfalles benutzen. Abspaltung von Tochterkolonien wurde nie beobachtet.
    Notes: Summary Mixed-species colonies ofPolyergus lucidus andFórmica schaufussi were studied in New York. Slave raids were conducted in late afternoon, past the peak in diurnal temperature. Multiple raids on differentFormica colonies were common, as were re-raids on the same colony. In laboratory nests, about 75% of the raidedFormica brood was eaten. Of 27 days on which raids occurred in the laboratory, 25 were onFormica nests souted on the day of the raid.Polyergus scouts are among the oldest individuals in the colony, and callows do not participate in scouting during the entire season of their eclosion. The group ofPolyergus workers that circle on the surface near the nest prior to raiding has a dynamic composition. The most frequent behavioral transition was from circling on one day to scouting on the next. The next most common change was from scouting to circling. The first scouting of the spring season occurred only one day after the appearance ofPolyergus larvae. The first slave raid was conducted 4 days later.Formica brood was present in freeliving colonies from 1–4 weeks earlier thanPolyergus brood in mixed nests. Although workers ofPolyergus were usually fed by regurgitation fromFormica, they occasionally drank and ate eggs independently. ThePolyergus queen was surrounded only byFormica workers.Polyergus eggs hatched into larvae in approximately 12 days, with the larval stage lasting an additional 9–12 days. Eclosion of callows took place within 20–23 days after pupation. Newly matedPolyergus queens follow slave raids and attempt adoption into target nests when theFormica are scattered during a slave raid. The process of budding was never observed.
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    Insectes sociaux 31 (1984), S. 473-475 
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Resume Ce travail contribue à la distinction taxonomique entreGoniomma hispanicum etG. baeticum, à partir de l'utilisation d'analyses multidimensionnelles menées sur dix variables définies sur le système de vénation de la première paire d'ailes de la femelle, et donne des résultats hautement significatifs.
    Notes: Summary This work helps in the taxonomical distinction betweenGoniomma hispanicum andG. baeticum, through the use of multidimensional analyses which were carried out on ten variables defined in the venation system of the first pair of wings on the female and gave highly significative results.
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    Pure and applied geophysics 11 (1948), S. 8-18 
    ISSN: 1420-9136
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    Topics: Geosciences , Physics
    Description / Table of Contents: Summary The vertical temperature gradient for selectet stations shows an annual variation which cannot be explained by the diurnal variation of temperature. The annual variation of temperature at fixed levels in the lower layers of atmosphere shows a trend opposite to these variations at fixed elevations in the middle layers. This fact indicates that the troposphere cannot be regarded as a layer of uniform structure. The interdiurnal variations of pressure and temperature for the individual levels and their opposite trend compel us to postulate within the troposphere a lower layer as has been observed before in various occasions and then called the layer of disturbation. It is possible to generalize these observations and to conceive of the lower layer as a planetary phenomenon and as the ground layer of the atmosphere.
    Abstract: Riassunto Il gradiente termico verticale presenta una variazione annuale che non può venir spiegata con la variazione diurna della temperatura. La variazione annuale della temperatura a livelli determinati nei bassi strati dell'atmosfera rivela un andamento opposto a quello che si riscontra negli strati centrali della troposfera. I due fatti dimostrano che la tropofera non può venir considerata come uno strato avente struttura uniforme. Le variazioni interdiurne della pressione e della temperatura nei singoli strati verticali ed il loro comportamento inverso conducono all'esistenza di uno strato inferiore in seno alla troposfera, già prima occasionalmente osservato e definito strato di perturbazione. Simili osservazioni sono atte a venir generalizzate in quanto questo strato inferiore è concepibile come fenomeno planetärio e come strato base dell'atmosfera.
    Notes: Zusammenfassung Der vertkkale Temperaturgradient hat bei ausgewahlten Stationen einen jährlichen Gang, der nicht durch den täglichen Temperaturgang erklärbar ist. Die jährliche Temperaturschwankung in Abhängigkeit von der Höhe zeigt ein gegenläufiges Verhalten zwischen den unteren und den mittleren Schichten der Troposphäre. Beide Erscheinungen weisen darauthin, dass man die Troposphäre nicht als eine Schicht von einheitlichem Aufbau ansehen kann. Die interdiurnen Anderungen von Druck und Temperatur in den einzelnen Höhenschichten und ihr gegenläufiges Verhalten zwingen dazu eine untere Schicht in der Troposphäre auszusondern, die scho gelegentlich früher beobachtet und dann als Störungsschicht bezeichnet wurde. Diese Beobachtungen sind aber einer Verallgemeinerung fähig, indem diese untere Schicht als planetarische Erscheinung aufzufassen und als Grundschicht der Atmosphäre zu kennzeichnen ist.
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    Pure and applied geophysics 119 (1980), S. 309-338 
    ISSN: 1420-9136
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    Topics: Geosciences , Physics
    Notes: Abstract The integral equation for the electromagnetic response of a sphere in a layered medium may be solved as follows. First, the unknown time harmonic electric field in the sphere is expanded in spherical vector waves. Secondly, the coefficients for these wave functions are found by a set of equations. The equations are found by multiplying the integral equation throughout by each wave function and integrating over the spherical conductor. Once the unknown coefficients have been determined, then the transient response may be found by taking the inverse Fourier transform. In carrying out the Fourier transform one learns that for most of the time range used in prospecting, only the lowest order vector wave function is significant. A study of the singularities of the spectrum of the transient shows that, for the time range considered, only a single branch cut is significant. There are no pole type responses. That is, the field does not decay exponentially. Previous studies of a sphere in free space reported only pole type responses. That is, at the later stages, the field decays exponentially. This study shows that, in order to model satisfactorily the effect of the host rock on transient electromagnetic fields, the sphere must be placed in layered ground.
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    Pure and applied geophysics 119 (1980), S. 392-403 
    ISSN: 1420-9136
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    Topics: Geosciences , Physics
    Notes: Abstract Tidal records at Hanasaki, southeastern Hokkaido, are analysed to clarify the post-seismic crustal vertical movement in the 1973 Nemuro-oki, Japan, earthquake. The result shows that the post-seismic uplift, as speculated byKasahara (1975), terminated in late 1975 and reverted to the previous rate of rapid subsidence of about 1 cm/yr. Ceasing of the post-seismic uplift, which occurred much earlier than previously speculated, could be explained by supplementary mechanisms, such as frictional resistance against creeping at the fault surface. This unexpected mode of movement, however, raises a new question about the accumulation of tectonic movements in this district. Since the subsidence rate extrapolated from geomorphological data for the past several thousand years is almost one order of magnitude lower than the recent rate as mentioned above, we have to provide some alternative explanation for the discrepancy between the two rates. In other words, simple repetition of co-, post- and inter-seismic movements in seismic cycles due to plate subduction, must be modified in this district. Several possible modifications to the subduction process are suggested, and a brief discussion of vertical movements expected in each case is given.
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    Pure and applied geophysics 119 (1980), S. 407-408 
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    Pure and applied geophysics 119 (1980), S. 409-442 
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    Pure and applied geophysics 119 (1980), S. 443-473 
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    Pure and applied geophysics 119 (1980), S. 491-500 
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    Pure and applied geophysics 119 (1980), S. 474-490 
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    Pure and applied geophysics 119 (1980), S. 510-514 
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    Pure and applied geophysics 119 (1980), S. 515-537 
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    Notes: Abstract Recent advances in the use of dynamical and statistical models to forecast the weather are described. High resolution physical-mathematical models can now predict the development of synoptic weather systems in great detail for a few days ahead, while large-scale phenomena like blocking can be predicted for about a week or more. The local forecasting problem is presently being attacked by statistical- and meso-scale models using the large-scale predictions as input parameters. Very encouraging results have been obtained to predict the local weather, in particular when the local weather is influenced by topography and the underlying surface.
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    Pure and applied geophysics 119 (1980), S. 538-547 
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    Pure and applied geophysics 119 (1980), S. 558-576 
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    Pure and applied geophysics 119 (1980), S. 548-557 
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    Pure and applied geophysics 119 (1980), S. 577-593 
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    Notes: Abstract In recent years there has been much progress in describing and understanding the detailed dynamical and microphysical structure of frontal precipitation systems. In this article we consider phenomena on a hierarchy of scales: the broad synoptic-scale flows in mid-latitude depressions, the mesoscale patterns of precipitation, the nature and origin of convection at the surface and aloft, and the microphysical properties of the resulting precipitation. The influence of orography is also briefly discussed.
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    Pure and applied geophysics 119 (1980), S. 798-808 
    ISSN: 1420-9136
    Keywords: Solar-terrestrial relationship ; Effect of sunspot numbers on monthly temperature/precipitation
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    Notes: Abstract Spectral analyses were made of derived area-index series of areas subject to extreme temperatures and precipitation as well as cross-spectral analyses of the area-index series with double sunspot cycle (Zurich) numbers. Superposed epoch analyses also were made of area-index series versus various double-sunspot cycle phases. Area series for wet and dry Junes, warm Junes, defined June drought, and warm Januaries all show statistically significant double sunspot cycle (∼21 year) periodicities. The 21-year cycle of above-normal June precipitation is most striking and has not received previous recognition.
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    Pure and applied geophysics 119 (1980), S. 809-815 
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    Keywords: Cloud dynamics ; Mixing process in cumulus clouds
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    Notes: Abstract An examination is made of the hypothesis that internal cloud properties are determined by the mixing of dry air from above the cloud top and cloud base air in such a way that the mixture is neutrally buoyant with respect to the clear air environment at each level. It is concluded that the resulting mixture is much drier than is actually observed. Comments are made about observed cloud properties which need to be taken into account in any model of the mixing process.
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    Pure and applied geophysics 119 (1980), S. 816-819 
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    Keywords: Cloud dynamics ; Mixing processes in cumulus clouds
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    Pure and applied geophysics 119 (1980), S. 820-830 
    ISSN: 1420-9136
    Keywords: Riming of ice crystals
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    Notes: Abstract Riming growth of ice particles is simulated by numerically solving the stochastic collection equations, simultaneously considering coagulation of water droplets. By introducing a special criterion which defines the habit of a riming particle, the influence of this habit on the growth of several kinds of ice particles assumed to be formed during riming was investigated. It was found that (i) hexagonal rimed ice plates are growing more efficiently than lump graupel or rimed columns, (ii) the use of different collection kernels for the lump graupel evolution leads to widely differing results and that (iii) the time dependent decrease of liquid water substance and the size of the resulting ice particles were more strongly influenced by the initial ice crystal concentration than by the initial ice crystal size and the habit of the ice particles. By decreasing the number density of ice crystals gradually a critical ice crystal concentration was found at which the present liquid water was not completely consumed by the riming process even after 1800 s model time, causing large drops of radii 〉100 μm to be formed in appreciable concentrations.
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    Pure and applied geophysics 119 (1980), S. 831-840 
    ISSN: 1420-9136
    Keywords: Extinction ; Radiation ; Turbidity
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    Notes: Abstract Helicopter measurements of solar irradiance and meteorological data within the atmospheric boundary-layer were made in Lagos during February 1979. Filter samples of aerosols were collected both during flight in February 1979 and at ground level in December 1978. Profile data on spectral aerosol optical depth were obtained and, from these, the aerosol extinction coefficient at two wavelengths (0.5 and 0.88 μm) were calculated. Precipitable water was low and was contained mainly within the 750 m layer above ground, suggesting the establishment of a deep unstable boundary layer. Calculated channel energy depletions by aerosols show that, within the first 750 m of the surface, the 0·88 μm might be more efficient at attenuating solar energy than 0·5 μm. The lagoon (maritime) aerosol sample indicated a more monodisperse size-distribution than the dusty harmattan aerosol sample.
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    Pure and applied geophysics 119 (1980), S. 888-892 
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    Pure and applied geophysics 119 (1981), S. 966-977 
    ISSN: 1420-9136
    Keywords: Streamer interactions
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    Notes: Abstract Investigation was carried out to study the interaction of positive streamers with charged and uncharged drops in a vertical electric field configuration. Results obtained for vertical and horizontal positions of the photographic films show that streamer interactions with neutral and negative drops are similar and further confirmed earlier results byPhelps (1972). It showed that indirect streamer interaction with droplets is effected by branches being sent to the drops from the main channel. The visibility of the branches on the Lichtenberg figures and the degree of interaction of streamers with drops depend on the drop size, its initial charge and shape, and/or the separation of the drops from the main channel. Suppression of streamer propagation among the positively charged drops was observed.
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    Pure and applied geophysics 119 (1981), S. 978-989 
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    Keywords: Ozone maxima ; Dry deposition ; Local cross-valley wind system
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    Notes: Abstract The diurnal cycle of ozone at the surface and within the PBL is examined. It is concluded that the intrusion of air masses from ozone-rich layers in the lower troposphere results in late evening ozone maxima observed at ground stations on mountain slopes as well as within distinct layers of the PBL above the valley bottom. The ozone-rich layers are assumed to exist due to meso- or large-scale horizontal transport of smog air masses and a local cross-valley wind system is shown to be responsible for the occurrence of the intrusion processes.
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    Pure and applied geophysics 119 (1981), S. 934-965 
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    Keywords: Condensation ; effect of entrainment on ; Cloud drop formation ; effect of entrainment on
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    Notes: Abstract It has been speculated for many years that the development of the droplet spectra in cloud is probably influenced by mixing processes. Various theoretical attempts to broaden the droplet spectra by mixing parcels with different velocity histories has shown that that particular effect is small. Similarly, very simpleuniform entrainment procedures did not lead to cloud drop size spectra which were broad enough, although by producing cloud drop size distributions with a double mode these models did substantially improve the drop size spectra of earlier adiabatic models which only exhibited a single mode. Recently a model based on entraining entities representing moving parcels of cloud air within the cloud was detailed byTelford andChai (1980). This study showed that the mixing in of dry air at cumulus turrets could lead to vertical cycling of diluted parcels, and that this cycling, with continual entrainment across the parcel boundaries, will produce much larger drops, as well as smaller drops of all sizes, in the droplet spectra. The ‘entity entrainment’ concept studied there appears to apply to the observations of stratus cloud discussed in this paper. This paper presents data taken in marine stratus off the California coast which give a particularly clear example of how such droplet spectra modification occurs in practice. Both large drops, and the spread of the spectra to smaller sizes, occur in relation to other variables in such a way as to be consistent with an entity entrainment explanation, with no other obvious possibility. In a marine stratus cloud just over 200 m thick and many tens of miles in extent we find clear evidence that dry air is mixing in at cloud tops. Strong vertical motion is to be found in the cloud, large sized drops are found in cloud parcels where the mixing gives lower droplet concentrations, and there is evidence that newly formed cloud parcels are warmer and contain many more smaller droplets. The observations show that immediately following entrainment of dry air drop diameters are not reduced appreciably, but, in the same parcels, drop concentrations have been reduced by a factor of ten or more. Further down in the cloud big drops, able to start growth by coalescence, are found associated with low total droplet concentrations. Overall, it seems likely from the consideration of these observations that the formation of the large drops which lead to precipitation processes in clouds depends critically on the mixing in of dry air at cloud tops, and very little on the size of the small drops resulting from the condensation nucleus counts. As a conclusion it appears reasonable to state that if entrainment occurs at cloud tops, then big drops will be formed!
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    Pure and applied geophysics 119 (1981), S. 1024-1036 
    ISSN: 1420-9136
    Keywords: Electromagnetic scattering ; VLF electromagnetic prospection
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    Notes: Abstract FollowingDmitriev (1960) a rigorous theoretical solution for the problem of scattering by a perfectly conducting inclined half-plane buried in a uniform conductive half-space has been obtained for plane wave excitation. The resultant integral equation for the Laplace transform of scattering current in the half-plane is solved numerically by the method of successive approximation. The scattered fields at the surface of the half-space are found by integrating the half-space Green's function over the transform of the scattering current. The effects of depth of burial and inclination, of the half-plane on the scattered fields are studied in detail. An increase in the depth of burial leads to attenuation of the fields. Inclination introduces asymmetry in the field profiles beside affecting its magnitude. Depth of exploration is greater for quadrature component. An interpretation scheme based on a phasor diagram is presented for the VLF-EM method of exploration for rich vein deposits in a conductive terrain.
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    Pure and applied geophysics 119 (1981), S. 1077-1092 
    ISSN: 1420-9136
    Keywords: Seismic hazard estimation ; Bohemia
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    Notes: Abstract The contribution reviews basic concepts of earthquake hazard assessment for sites of nuclear power plants. Taking into account the delineation of earthquake source regions, intensity-frequency relations, upper intensity thresholdsI max and intensity attenuation curves, we determine the seismic hazard for a site in south Bohemia and calculated the quantities defining the seismic hazard, i.e. return period in years, probability of exceedance for different intensities and different periods of interest. The adopted procedure has some limitations due to the poor definition of seismogenic zones (boundaries,N(I),I max) and lack of strong motion observations in Central Europe.
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    Pure and applied geophysics 119 (1981), S. 1125-1133 
    ISSN: 1420-9136
    Keywords: Seismicity and crustal structure
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    Notes: Abstract Focal solutions of four strong earthquakes and P signals of twenty-four smaller shocks of the active Mur-Mürz Valley, the Semmering Pass and the Vienna Basin. An ‘equivalent slip rate’ of 0.03 This feature agrees with the model of a subsiding Pannonian Basin. An ‘equivalent slip rate’ of 0.03 cm/year is roughly estimated from earthquake data 1903–1978. This rate does not include the creep rate, but it gives an idea of the magnitude of speed of geological processes in this area. Refraction seismic data from the Alpine Longitudinal Profile 75 shows a low velocity zone in the upper crust of the seismic active East Alpine area but not in the aseismic part of the Pannonian Basin. The eastern margin of the Eastern Alps and the Carpathians limits the Pannonian Basin, which has a special and interesting geological history. Many authors (Szadezky-Kardoss, 1966;Stegena, Ceszy andHorvàth, 1975) presented models of the genesis of the Pannonian Basin. They apply the concept of the ‘mantle diapirs’ to explain the following facts: subsiding of the Pannonian Plate in comparison to the Alps, high terrestrial heat flow within the Pannonian Plate, decrease of the Moho depth from 40 km below the Eastern border of the Alps to 27 km below the Pannonian Basin. They claim that the Alpine-Carpathian interarc and basin represent the final stage of an orogenetic system where ‘subcrustal erosion’ leads to a thinning of the crust. Consequently the surface subsides and is covered by young sediments. They proved that this subsidence and sedimentation is more or less in isostatic equilibrium. The aim of this paper is to provide new arguments using focal solutions and refraction seismic investigations.
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    Keywords: Caucasus ; Three-dimensional seismic modelling
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    Notes: Abstract This paper deals with a procedure of a joint analysis of seismic data from earthquakes and those obtained by DSS. The DSS data are used as a first approximation to construct a two-dimensional model of the medium made up of individual blocks. These models serve as a basis when constructing specific three-dimensional travel-time curves. These travel-time curves are further used for the calculation of hypocenter parameters in a laterally inhomogeneous block medium. The hypocenter field and the travel times obtained are input data for the computation of three-dimensional fields of velocities in earthquake focal zones. Results of applying the proposed procedure to the Caucasus region are presented.
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    Pure and applied geophysics 12 (1948), S. 1-3 
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    Description / Table of Contents: Summary The exceptional thermic conditions of the winter 1946–47 and the summer 1947 are discussed. These conditions do not mean a change of the climate of Western Europe. They concide with a period of intensive solar activity. Generally narrow connexion are present between periods of large (small) variability of the climate and large (small) solar activity.
    Notes: Résumé Les conditions thermiques exceptionelles de l'hiver 1946–47 et de l'été 1947 sont discutées en déduisant que cela ne signifie pas un changement de climat pour l'Europe occidentale: en effet, il s'agit seulement d'une coincidence avec une période d'intense activité solaire, y ayant en général une correspondance entre les époques de grande (ou petite) variabilité du climat et les périodes de forte (ou faible) activité solaire.
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    Pure and applied geophysics 12 (1948), S. 23-52 
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    Description / Table of Contents: Summary The purpose of the experiments described in this paper was to investigate the conditions of propagation of a transmitter situated below the surface of the ground. This problem is of interest to both radio engineers and geophysicists. By determination of the extinction and reflection areas of electrical discontinuity may be located. The experiments were carried out in German potassic salt mines. Rocks of potassic salts are known as very bad conductors. Therefore the extinction is but very little. In this area ranges up to 14 kilometres were reached. This is the greatest range obtained up to now under the surface of the ground. The investigations were carried out with different wave lengths from 10 up to 2000 metres. The influence of geological discontinuities, alkaline deposits and disturbed areas was always very great. The author mentions that the above ranges could certainly still be considerably increased by application of all technical means available at present.
    Notes: Zusammenfassung 1) Die Versuche fanden in den Gruben Hannovers, des Werragebietes und des Südharzes statt. 2) Die Untersuchungen erstreckten sich über das ganze praktisch in Betracht kommende Wellenband, angefangen von den Meterwellen bis in den 1000 Meter-Bereich. 3) Im Zuge der Untersuchungen konnten die bisher grössten, unter Tag überhaupt erzielten Reichweiten erreicht werden. Die grösste Reichweite wurde zwischen zwei Hannoverischen Gruben erzielt und betrug bei 14 Kilometer. 4) Frequenz und geologische Faktoren sind stets von Einfluss. 5) Die Versuche zeigen, dass unter Kalilagerstätten Funkmutungsverfahren nach dem Reflexions- und Refraktionsprinzip für grössere Aufschlussteufen möglich sind. 6) Die Versuche haben alle Voraussetzungen des Grubenfunks so weit geklärt, dass dessen praktischer Einführung nichts im Wege steht.
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    Pure and applied geophysics 12 (1948), S. 108-112 
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    Pure and applied geophysics 12 (1948), S. 105-107 
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    Pure and applied geophysics 12 (1948), S. 121-126 
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    Description / Table of Contents: Zusammenfassung Die in Uppsala registrierte Bodenunruhe ist für die Zeit 1907–1947 betreffs langperiodischen Schwankungen untersucht worden. Eine 11-jährige Variation wird festgestellt und es gibt weiter Anzeichnungen einer Variation von 28 Monaten. Die 11-jährige Variation ist seit 1923 zur Sonnenflecken-frequenz negativ korreliert und ist durch entsprechende meridionale Verschiebungen der am meisten betretenen Zyklonenbahnen, erklärt.
    Abstract: Riassunto L'agitazione microsismica registrata a Uppsala nel quarantennio 1907–1947 venne esaminata in vista di determinare le oscillazioni di lungo periodo. Si è accertata una oscillazione undecennale, trovandosi altresi indizi per una oscillazione di 28 mesi. Dal 1923 l'oscillazione undecennale manifesta una correlazione negativa con la frequenza delle macchie solari e viene spiegata con i corrispondenti spostamenti meridionali delle rotte cicloniche dominanti.
    Notes: Summary The microseisms recorded at Uppsala have been studied for the time 1907–1947 with regard to long period variations. There is clear evidence of an 11 year variation and slight indications of a 28 month variation. The 11 year variation is from 1923 negatively correlated to the sunspot frequency and is explained by corresponding meridional displacements of the dominant cyclonic tracks.
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    Pure and applied geophysics 12 (1948), S. 168-169 
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    Pure and applied geophysics 12 (1948), S. 134-144 
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    Description / Table of Contents: Summary It was yet often noted that the earth's magnetic field has been steadily modified on the result of seismic earth movements. The author cites many recent examples of magnetic anomalies measured in Japan after major earthquakes (Kato). The «Bassin de Paris»'s magnetic anomaly is modified during a certain time in a possible connection with magmatic removals and with some seismic activity. The earthquake of June 11 th., 1938 in Belgium shows some very interesting connections with the belgian magnetic anomaly. Suggestive relationships are noted between changes in the earth's secular magnetic field and areas of seismicity (Omer). The author thinks that the earthquakes and the deformations of the earth's magnetic field are more or less closely connected one with another, and it may perhaps be that the atomic energy (chain reactions) may explain some orogenic earthquakes and their aftershocks.
    Notes: Résumé On a déjà souvent signalé que le champ magné ique terrestre s'est trouvé modifié de façon durable à la suile de mouvements séismiques. L'auteur rappelle plusieurs exemples récents d'anomalies magnétiques mesurées au Japon à la suite d'importants séismes (Kato). L'anomalie magnélique duBassin de Paris se déforme dans le temps en liaison possible avec des déplacements magmatiques et une activité séismique avortée. Le séisme du 11 juin 1938 en Belgique montre d'intéressants rapports avec l'anomalie magnétique belge. Les cartes isoporiques mondiales présentent des relations avec les cartes de séismicité (Omer). L'auteur pense que séismes et déformations du champ magnétique terrestre sont plus ou moins étroitement liés et que peut être une réaction atomiqueen chaine peut expliquer les séismes orogéniques et leurs répliques.
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    Pure and applied geophysics 12 (1948), S. 286-292 
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    Pure and applied geophysics 12 (1948), S. 295-296 
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    Pure and applied geophysics 120 (1982), S. 79-94 
    ISSN: 1420-9136
    Keywords: Monsoon ; Rainfall ; Tropical meteorology
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    Notes: Abstract The paper deals with an application of a stochastic model to the frequency and duration of precipitation events. With the aid of the model, the magnitudes ofmth highest rainfall amount in 24 hours' duration with 97.5% probability are obtained for various climatic regimes over a tropical monsoon region. There is good agreement between them-day minimum rainfall estimated through the model and the observed value. The model satisfactorily explains the frequency of the extreme rainfall event.
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    Pure and applied geophysics 120 (1982), S. 249-260 
    ISSN: 1420-9136
    Keywords: Correlation function ; Interpolation ; Network design
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    Notes: Abstract The study examines the correlation function of tropical monsoon rainfall on monthly, seasonal and annual time scales and obtains the relationship between this function and the distance. The area selected for study is Vidarbha with a fairly dense network of rain gauges. Vidarbha is a meteorological sub-division of the state of Maharashtra in India. Utilizing the relationship between the correlation function of the rainfall field and the distance, the errors of optimum interpolation of rainfall at a point have been computed by applying the method of optimum interpolation byGandin (1970). Relationships between the errors of interpolation and distance have been evaluated and from this the maximum spacing allowed between rain gauges for a specified tolerable error in interpolation has been estimated for each of the periods.
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    Pure and applied geophysics 122 (1984), S. 680-693 
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    Keywords: Physical seismic models ; Uniaxial loading ; Shear displacement ; Locked zone ; Seismoactivity
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    Notes: Abstract Square plate models with a diagonally located slit in compression were studied photoelastically. The resulting stress field surrounding the discontinuity (slit) is evaluated before and after seismoactive (seismic-energy-releasing) shear displacement. The mechanism of the fast shear movement (stick-slip), including its radiation properties, in interpreted. The results confirm the existence of a central locked zone in the loaded slit, the limits of which coincide with the initiation points of stick-slip movements. The zone is interpreted as the source of the seismic energy release. The complementary measurements (direct optical and ultrasonic) are presented to verify the results of the photoelastic analysis. The results obtained are discussed in regard to the conclusions that follow from the theory of elasticity.
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    Pure and applied geophysics 122 (1984), S. 763-763 
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    Pure and applied geophysics 122 (1984), S. 747-762 
    ISSN: 1420-9136
    Keywords: Total ozone ; Periodicities
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    Notes: Abstract Total ozone data series for 1957–82 at ten locations were subjected to Maximum Entropy Spectral Analysis. Besides the annual, semi-annual, and quasi-biennial oscillations, peaks were noticed at 3.5–4, 6–7, and 10–11 years. For Arosa, Switzerland, for a longer period (1932–71), an additional peak was indicated at about 16 years.
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  • 84
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    Keywords: precursory ground tilt ; temporal variation of crustal deformation ; the 1944 Tonankai earthquake ; leveling survey ; earthquake prediction
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    Notes: Abstract The temporal variation in precursory ground tilt prior to the 1944 Tonankai (Japan) earthquake, which is a great thrust-type earthquake along the Nankai Trough, is discussed using the analysis of data from repeated surveys along short-distance leveling routes.Sato (1970) pointed out that an anomalous tilt occurred one day before the earthquake at Kakegawa near the northern end of the focal region of the earthquake. From the analysis of additional leveling data, Sato's result is re-examined and the temporal change in the ground tilt is deduced for the period of about ten days beginning six days before the earthquake. A remarkable precursory tilt started two or three days before the earthquake. The direction of the precursory tilt was up towards the south (uplift on the southern Nankai Trough side), but the coseismic tilt was up towards the southeast, perpendicular to the strike of the main thrust fault of the Tonankai earthquake. The postseismic tilt was probably opposite of the coseismic tilt. The preseismic tilt is attributed to precursory slip on part of the main fault. If similar precursory deformation occurs before a future earthquake expected to occur in the adjacent Tokai region, the deformation may help predict the time of the Tokai earthquake.
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    Pure and applied geophysics 122 (1984), S. 781-792 
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    Keywords: Precursory tilt ; aseismic slip ; thrust faulting
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    Notes: Abstract During three years preceding the 1976 Friuli earthquake, a continuous southward ground tilt was recorded by a tiltmeter placed near Tolmezzo, 15 km north-west of the epicentre of the impending earthquake. The cumulative ground tilt amounted to as much as 3 minutes of arc. Since the tiltmeter was placed in the proximity of an active fault, such a tilt can be explained if the fault slipped aseismically on its shallower section during the same three year period. Aseismic slip on the fault might have been caused by the same mechanism which concentrated stress in the region and eventually produced the 1976 earthquake.
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    Pure and applied geophysics 122 (1984), S. 793-811 
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    Keywords: Earthquake prediction ; Instability ; San Andreas fault
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    Notes: Abstract The locked section of the San Andreas fault in southern California has experienced a number of large and great earthquakes in the past, and thus is expected to have more in the future. To estimate the location, time, and slip of the next few earthquakes, an earthquake instability model is formulated. The model is similar to one recently developed for moderate earthquakes on the San Andreas fault near Parkfield, California. In both models, unstable faulting (the earthquake analog) is caused by failure of all or part of a patch of brittle, strain-softening fault zone. In the present model the patch extends downward from the ground surface to about 12 km depth, and extends 500 km along strike from Parkfield to the Salton Sea. The variation of patch strength along strike is adjusted by trial until the computed sequence of instabilities matches the sequence of large and great earthquakes sincea.d. 1080 reported by Sieh and others. The last earthquake was theM=8.3 Ft. Tejon event in 1857. The resulting strength variation has five contiguous sections of alternately low and high strength. From north to south, the approximate locations of the sections are: (1) Parkfield to Bitterwater Valley, (2) Bitterwater Valley to Lake Hughes, (3) Lake Hughes to San Bernardino, (4) San Bernardino to Palm Springs, and (5) Palm Springs to the Salton Sea. Sections 1, 3, and 5 have strengths between 53 and 88 bars; sections 2 and 4 have strengths between 164 and 193 bars. Patch section ends and unstable rupture ends usually coincide, although one or more adjacent patch sections may fail unstably at once. The model predicts that the next sections of the fault to slip unstably will be 1, 3, and 5; the order and dates depend on the assumed length of an earthquake rupture in about 1700.
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    Pure and applied geophysics 118 (1980), S. 86-127 
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    Keywords: Stratosphere ; Aerosol layer ; Sulfates
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    Notes: Abstract After briefly reviewing the observational data on the stratospheric sulfate aerosol layer, the chemical and physical processes that are likely to fix the properties of the layer are discussed. We present appropriate continuity equations for aerosol particles, and show how to solve the equations on a digital computer. Simulations of the unperturbed aerosol layer by various published models are discussed and the sensitivity of layer characteristics to variations in several aerosol model parameters is studied. We discuss model applications to anthropogenic pollution problems and demonstrate that moderate levels of aerospace activity (supersonic transport and space shuttle operations) will probably have only a negligible effect on global climate. Finally, we evaluate the possible climatic effect of a ten-fold increase in the atmospheric abundance of carbonyl sulfide.
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    Pure and applied geophysics 118 (1980), S. 3-19 
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    Keywords: Ultraviolet radiation ; Photodissociation ; Schumann-Runge bands ; Herzberg continuum ; Ozone bands
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    Topics: Geosciences , Physics
    Notes: Abstract Solar radiation of λ〉175 nm and of Lyman-alpha at 121.6 nm is absorbed in the mesosphere and stratosphere by molecular oxygen (λ〈242 nm) and also by ozone molecules at λ〉200 nm. This paper describes the photodissociation processes resulting from absorption in the Schumann-Runge bands and Herzberg continuum of molecular oxygen and also in the Hartley, Huggins and Chappuis bands of ozone. Special consideration is given to differences between the stratospheric and mesospheric problems.
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    Pure and applied geophysics 118 (1980), S. 58-85 
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    Keywords: NO2 distribution ; Ozone destruction by NO x
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    Notes: Abstract The catalytic destruction of stratospheric ozone by the oxides of nitrogen is believed to be an important part of the global ozone balance. The lack of sufficient measurements of NO x concentrations has impeded efforts to quantify this process. Recent measurements of stratospheric nitrogen dioxide from ground-based stations as well as aircraft and balloons have provided a first approximation to a global distribution of NO2 vertical columns at sunset. These observed vertical columns have been translated into time-dependent vertical NO2 profiles by means of a one-dimensional atmospheric photochemical model. Using recent observations of air temperature and ozone along with this information, the independent instantaneous (one second) rates of ozone production from oxygen photolysis P(O3), of ozone destruction from pure oxygen species (Chapman reactions) L(O x ), and of ozone destruction by nitrogen oxides L(NO x ) were estimated over the three-dimensional atmosphere. These quantities are displayed as zonal average contour maps, summed over various latitude zones, summed over various altitude bands, and integrated globally between 15 and 45 km. Although the global summation between 15 and 45 km by no means tells the complete story, these numbers are of some interest, and the relative values are: P(O3), 100; L(O x ), 15; L(NO x ), 45±15. It is to be emphasized that this relative NO x contribution to the integrated ozone balance is not a measure of the sensitivity of ozone to possible perturbations of stratospheric NO x ; recent model results must be examined for current estimates of this sensitivity.
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    Pure and applied geophysics 118 (1980), S. 128-151 
    ISSN: 1420-9136
    Keywords: Galactic cosmic rays ; Solar proton events ; Particle precipitation ; Chemistry
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    Notes: Abstract An assessment is made of the relative contribution of certain classes of energetic particle precipitation to the chemical composition of the middle atmosphere with emphasis placed on the production of odd nitrogen and odd hydrogen species and their subsequent role in the catalytic removal of ozone. Galactic cosmic radiation is an important source of odd nitrogen in the lower stratosphere but since the peak energy deposition occurs below the region where catalytic removal of O3 is most effective, it is questionable whether this mechanism is important in the overall terrestrial ozone budget. The precipitation of energetic solar protons can periodically produce dramatic enhancement in upper stratospheric NO. The long residence time of NO in this region of the atmosphere, where catalytic interaction with O3 is also most effective, mandates that this mechanism be included in future modelling of the global distribution of O3. Throughout the mesosphere the precipitation of energetic electrons from the outer radiation belt (60°≲Λ≲70°) can sporadically act as a major local source of odd hydrogen and odd nitrogen leading to observable O3 depletion. Future satellite studies should be directed at simultaneously measuring the precipitation flux and the concomitant atmosphere modification, and these results should be employed to develop more sophisticated models of this important coupling.
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    Pure and applied geophysics 118 (1980), S. 177-188 
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    Keywords: Inertio-gravity waves ; Stokes drift ; Lagrangian-mean flow
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    Notes: Abstract Using standard ‘two-scaling’ techniques we calculate the Eulerian- and Lagrangianmean flows induced at second order in amplitude by small-amplitude, transient, non-dissipative, vertically-propagating inertio-gravity waves on anf-plane. The example is an idealized one, but illustrates a number of important features that are typical of wave, mean-flow interaction in a rotating, stratified fluid. Physical discussion of the solution is given in Section 4 of the review byMcIntyre (1980), which appears elsewhere in this issue.
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    Pure and applied geophysics 118 (1980), S. 35-57 
    ISSN: 1420-9136
    Keywords: Solar occultation technique ; Analysis of technique ; Inversion procedures
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    Topics: Geosciences , Physics
    Notes: Summary This article analyzes the nature of the aerosol information that current or planned spacecraft measurements could contribute toward the required input data for studies of natural anthropogenic influences on the middle atmosphere, and their consequent effects on our weather and climate. The analysis is conducted with particular reference to the solar occultation sounding technique as applied by the SAGE I experiment on the Atmospheric Explorer Mission B spacecraft. Its conclusions should prove to be of use in both the interpretation of the SAGE I data, and in the design of the follow-on mission on the Earth Radiation Budget satellite. Our analysis shows, in particular, that further studies are required in: the choice and number of sounding channels; the data taking sequence in relation to the atmospheric regions probed; the accuracy and vertical resolution of the atmospheric profiling, and their dependence on both the instrument/spacecraft parameters and the data inversion techniques; and the data reduction procedures. Neither of the selected channels is in a one-to-one relationship with an atmospheric constituent; hence, unless further assumptions are introduced, inversion techniques based on such a property are not applicable. The aerosol wavelengths are not satisfactory as they are only sensitive to the large size tail of the aerosol size distribution rather than to the predominant sizes; for these, UV wavelengths would be required. Owing to the change of the Sun's shape due to atmospheric refraction as the Sun either sets or rises, the higher altitudes will be scanned fewer times than the lower altitudes. Also, because transmission approaches rapidly unity above ∼40 km, the same high altitudes are more sensitive to measurement errors-errors that will propagate to lower altitude determinations when inverted profiles are reconstructed from the top of the atmosphere. These two factors, combined with the small air mass values at the high altitudes, are the cause of the mathematical ill-conditioning of the inversion problem. They point toward the need for a data-taking sequence strategy that would trade off between data storage and transmission constraints, larger accuracy at the high altitudes, and proper division of the atmosphere in order to overcome the ill-conditioning. Likewise, and as a result of the above considerations, there is a need for a detailed trade off study between data accuracy and vertical resolution of the reconstructed profiles. This should take into account the seasonal and geographical variations in the distribution of atmospheric constituents, as well as a representative statistical set at any given location and time, appropriate error measures and their vertical profiles, and several inversions utilizing as initial guesses profiles that depart from the true ones. It is also shown that the aerosol and ozone number densities cannot be recovered simultaneously without introducing some formula for the aerosol extincition or assumptions on the form of the aerosol size distribution. This problem is not resolved by the addition of sounding channels because each such channel introduces an additional unknown aerosol extinction. Thus, one is led to a separate rather than a simultaneous determination of the various constituents by resorting to complementary measurements. For a future experiment, it is suggested to determine the ozone separately from measurements at a close pair of appropriate wavelengths between which the aerosol extinction varies slowly whereas that of ozone exhibits a rapid variation. A similar technique could also be used for the separate determination of NO2. The relaxation-type of inversion suggest byChu andMcCormick (1979) does not seem to be appropriate because each channel is not sensitive selectively to an individual constituent, the aerosol channels are not sensitive to the important sizes in the distribution, and the sensitivity of the channels to the constituents of interest varies greatly with altitude. In the retrieval of the vertical profiles, the cause of the ill-conditioning of the inversion is identified. Two approaches are suggested for overconing this problem: (i) build the profile starting from the top of the atmosphere (forward procedure) but with an initial layer of sufficient air mass, or preferably (ii) reconstruct the profile from the lowest altitude reached (backward procedure) with a renormalization at the top of the atmosphere. In this process, the minimization search method (Fymat, 1976) would appear to be a better technique than the onion-peeling technique, as demonstrated byMill andDrayson (1978). In order to maximize the scientific return of SAGE I, a data inversion procedure is proposed. It assumes that (i) there are no aerosols above ∼25 km, and no NO2 below this altitude (as suggested byChu andMcCormick, 1979), (ii) below ∼25 km, ozone (and NO2, if present) could be determined separately, and (iii) the aerosol has a known refractive index at all wavelengths of interest, is assumed to be spherical (or describable in terms of ‘equivalent spheres’), and the minimum and maximum radii of its size distribution are known a priori. Under these assumptions, it is possible to retrieve the neutral density, NO2 and O3 profiles above ∼25 km, by either the forward or the backward procedure described above. Taking into consideration the power law variation of the air density with altitude, it is further possible to reconstruct the corresponding profiles at all the lower altitudes from the determinations in the altitude range ∼30–40 km. Below ∼25 km, the four SAGE I channels would then all become available for the aerosol inversion. While the profile reconstruction could proceed as for the higher altitudes, the aerosol inversion at each individual altitude presents problems of its own. Results of numerical experiments for aerosol inversion using all four SAGE wavelengths and seven different inversion routines are presented. If good a priori information is available on the sought size distribution solution, reasonably satisfactory inversions can be performed (see line 1 of Table 2, and Fig. 3c and 3d). However, in the absence of such information, there are as many solutions as inversion methods tried, in complete conformity with the well-known ill-conditioning of the problem. Among methods providing physically meaningful solutions, no method could be singled out as preferable to the others. In these inversions, the data were assumed to be exact, and 99% of the distribution were used. Under different conditions, the nonuniqueness of the inversion would be further compounded. Lastly, based on the present study, a strategy is suggested for the design and data interpretation of a follow-on SAGE-type experiment. Considering the important advantages to this problem presented by forward scattering, as demonstrated byFymat andMease (1978), a composite (extinction-forward scattering) experiment is recommended for the future experiments.
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    Pure and applied geophysics 118 (1980), S. 775-782 
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    Keywords: Aerosol extinction ; Solar radiation ; Tropical meteorology
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    Notes: Abstract Solar radiance measurements covering over seventeen months are analysed for a location beside the Lagos Lagoon. The aerosol extinction coefficient was generally higher in the dusty months than in the wet months. ‘Clean air’ estimates of the coefficient are made. Data on its wavelength dependence are also presented.
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    Pure and applied geophysics 118 (1980), S. 823-830 
    ISSN: 1420-9136
    Keywords: Rayleigh wave dispersion in Apulia ; Upper mantle structure of Apulia ; Apulia, upper mantle structure
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    Notes: Abstract Phase velocities of Rayleigh waves for the Adriatic Sea area are obtained in the period range 25–190 sec along the path (l'Aquila-Trieste) AQU-TRI and 20–167 sec along the path (Trieste-Bari) TRI-BAI. The phase velocities are systematically higher than the known values for the surrounding regions. The data inversion indicates the presence of a lithosphere typical of stable continental areas with clear high-velocity lid (V s ∼4.6 km/sec) overlying a well developed low velocity zone (V s ∼4.2 km/sec).
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    Pure and applied geophysics 119 (1980), S. 841-853 
    ISSN: 1420-9136
    Keywords: Resistivity ; inversion techniques
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Model uncertainty is introduced into direct-current resistivity data by adding random changes to layer thicknesses in a ten-layer model. The resulting information is then aliased by generating a sounding curve which contains less information than the ten resistivities and nine thicknesses. These sounding curves are then inverted via the Backus-Gilbert algorithm using singular value decomposition to obtain solutions in terms of simpler two-or three-layer models. Quantitative results confirm what has been known qualitatively for many years as the principle of equivalence. An interesting result is that the geometric average of a given suite of noisy models is virtually identical to the best-fit model for the average of the noisy curves. The results show that the inversion of resistivity data by nonlinear least-squares parameter fitting is stable in the sense that noise in the data inverts to the same magnitude of noise in the model.
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  • 96
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    Pure and applied geophysics 118 (1980), S. 355-377 
    ISSN: 1420-9136
    Keywords: Ozone depletion ; Chlorofluorocarbons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Results are presented from a two-dimensional, time-dependent model of the atmosphere which has been used to investigate perturbations to the ozone layer due to chlorofluorocarbons. The unperturbed stratosphere is modelled well with the observed features of the ozone distribution reproduced. The main features of the perturbation calculations are the large latitudinal and seasonal variations found in the modelled ozone reductions with greates reductions where the total ozone amounts are largest. The importance of at least a two-dimensional study in problems of this kind is stressed and the important role of dynamical and radiative processes, as well as chemical, is indicated.
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  • 97
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    Pure and applied geophysics 12 (1948), S. 293-294 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
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  • 98
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    Pure and applied geophysics 12 (1948), S. 210-253 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Description / Table of Contents: Summary In continuing former studies about the USA and in employing the recent observations—especially the ascents of radio-sounds—this investigation treats the average thermical conditions over the North-American continent in dependance from time and space till a height of about 20 km. The influences of the three geographical coordinates, i. e. latitude, longitude and height, and of the factor of time are developed gradually. The resulting consequences concerning the average conditions of pressure and air moving are derived and interpreted. In this manner one particularly succeeds in proving the effects of the distribution of the temperature on the planetary wind circulation, its modifications by the monsoon tendency and the component of the interhemispherical air circulation in the troposphere and in the stratosphere; a problem that has been explored relatively seldom till now. Furthermore the variations of the tropopause in time and space are shown. The study being a further contribution to a systematical development of a world-wide climatology of the free atmosphere will help to enlarge the necessary empirical foundation for all the theoretical speculations of the general circulation in the third dimension.
    Notes: Zusammenfassung In Fortführung früherer analoger Untersuchungen über die USA behandelt die vorstehende Arbeit unter Benutzung der seither hinzugekommenen Beobachtungen (namentlich von Radiosonden-Aufstiegen) die durchschnittlichen raum-zeitlichen Temperaturverhältnisse über dem nordamerikanischen Erdteil bis über 20 km Höhe. Die Einflüsse der drei geographischen Koordinaten: Breite, Länge, Höhe und des Zeitfaktors werden schrittweise herausgearbeitet, die sich daraus ergebenden Folgen für die mittleren Druck- und Bewegungsbedingungen abgeleitet und interpretiert. Auf diese Weise lassen sich insbesondere auch die Wirkungen der Temperaturverteilung auf die planetarische, die monsunale und die relativ noch wenig erforschte Komponente der interhemisphärischen Zirkulation in Tropo- und Stratosphäre, sowie die raum-zeitlichen Änderungen ihrer Trennungsfläche, der Tropopause, nachweisen. Die Arbeit ist im ganzen gedacht als ein weiterer Beitrag zur systematischen Entwicklung einer weltweiten Klimatologie des freien Luftmeeres, die das notwendige empirische Fundament für alle theoretischen Eröterungen des allgemeinen atmosphärischen Kreislaufs nach der dritten Dimension ausbauen soll.
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  • 99
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    Pure and applied geophysics 120 (1982), S. 67-78 
    ISSN: 1420-9136
    Keywords: Monsoon ; Transport ; Tropical meteorology ; Water vapour
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The advective monthly mean transfer of water vapour in the layer below 700 mbar is investigated for India for the years 1962 to 1972 and for the months January to September. The average zonal and meridional components of the transfer of water vapour for India are obtained. They are further averaged for different combinations of the pre-monsoon months from January to May and are correlated with the summer monsoon rainfall. The correlation coefficients for zonal transfer of water vapour are either negative or small positive for different combinations of the months mentioned above. The correlation coefficients for the meridional transfer of water vapour are positive. The maximum value is 0.74 for the March to May combination and is statistically significant at the 1% level. An extensive investigation is, therefore, made for the March to May averages of water vapour transfer for four broad regions of India. The parameters of water vapour transfer for these regions are compared with the threshold values and the prediction category, normal or drought, for the subsequent summer monsoon season is determined for all years. The correlation coefficient between the index of drought, as determined from parameters of water vapour transport and rainfall departure, is statistically significant at the 2% level.
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  • 100
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    Pure and applied geophysics 120 (1982), S. 123-135 
    ISSN: 1420-9136
    Keywords: Tropical meteorology ; Atmospheric electricity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The results of atmospheric electric measurements over a twenty year period (1961–1980) are reviewed for Ibadan situated in the tropical rain forest of Nigeria. The aim is to present the data in an easily accessible form.
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