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  • Articles  (60)
  • evolution  (60)
  • Springer  (60)
  • American Chemical Society
  • Emerald
  • 1995-1999  (60)
  • 1997  (60)
  • 1
    Electronic Resource
    Electronic Resource
    Genetics of the ability of Phyllotreta nemorum larvae to survive in an atypical host plant, Barbarea vulgaris ssp. arcuata (1997)
    Springer
    Entomologia experimentalis et applicata 82 (1997), S. 37-44 
    Details
    ISSN: 1570-7458
    Keywords: Barbarea vulgaris ; Cruciferae ; Phyllotreta nemorum ; Chrysomelidae ; Alticinae ; flea beetle ; plant defence ; genetics ; sex-linkage ; X- and Y-chromosome ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A polymorphism in host plant exploitation has been discovered in the flea beetle, Phyllotreta nemorum L. (Coleoptera: Chrysomelidae: Alticinae) where one resistant population is able to use Barbarea vulgaris R.Br. ssp. arcuata (Opiz.) Simkovics (Brassicaceae) as a host plant while a susceptible population is not. Crosses (F1, F2, and backcrosses) between the two flea beetle populations were made, and survival of the progeny on B. v. ssp. arcuata was measured. The ability of P. nemorum larvae to survive in this plant species depended on the presence of major, dominant genes (R-genes). The two most abundant R-genes in the resistant flea beetle population were X- and Y-linked, respectively. The use of B. v. ssp. arcuata as a natural host plant by the resistant population of P. nemorum seems to be an extension of the host plant range of the species. The role of sex-linked genes in the evolution of host range is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1002938912809
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  • 2
    Electronic Resource
    Electronic Resource
    Variation in defences of the plant Barbarea vulgaris and in counteradaptations by the flea beetle Phyllotreta nemorum (1997)
    Springer
    Entomologia experimentalis et applicata 82 (1997), S. 25-35 
    Details
    ISSN: 1570-7458
    Keywords: Barbarea vulgaris ; Cruciferae ; Phyllotreta nemorum ; Chrysomelidae ; Alticinae ; flea beetle ; plant defence ; resistance ; host plant ; variation ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Several sorts of variation in the interaction between the insect, Phyllotreta nemorum L. (Coleoptera:Chrysomelidae:Alticinae), and the plant, Barbarea vulgaris R.Br. (Brassicaceae), have been discovered: 1) genetic differences in the levels of defences in the plant, 2) genetic differences in the ability of insects to cope with the plant defences, 3) seasonal variation in levels of defences in the plant, and 4) differences between leaf types in levels of defences. Two plant accessions were suitable for larval development throughout the season while the remaining nine accessions were more or less unsuitable for larvae from the ‘susceptible’ T-population at least at certain times of the year. All accessions were suitable for the ‘resistant’ E-population throughout the year. There was a seasonal variation in levels of defences in some accessions which were unsuitable for the T-population during the summer period when beetles were present, but not during autumn and spring when the beetle were hibernating. Upper (younger) cauline leaves of these accessions had higher levels of defences than lower (older) cauline leaves. The resistant E-population used B. vulgaris as a natural host plant while the susceptible T-population did not. The use of B. vulgaris as a natural host plant by the E-population of P. nemorum seems to be an extension of the host plant range of the species. Variation in plant defences may have facilitated the switch in host plant use by the resistant flea beetle population.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1002990929647
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  • 3
    Electronic Resource
    Electronic Resource
    Colonization and evolution of lakes on the central Norwegian coast following deglaciation and land uplift 9500 to 7800 years B.P. (1997)
    Springer
    Journal of paleolimnology 18 (1997), S. 269-281 
    Details
    ISSN: 1573-0417
    Keywords: colonization ; evolution ; lakes ; Norway ; deglaciation ; land uplift ; invertebrates ; Chironomidae ; Porifera ; Bryozoa ; diatoms ; Charophyta ; tsunami
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Invertebrate colonization of lakes following the uplift of land from the sea was studied in four lakes, currently situated between 39 and 24 m a.s.l., on the central Norwegian coast. The lakes were isolated from the sea between 9500 and 7700 years B.P. Animal and algal remains picked from core samples showed that the first colonizers preserved as fossils were usually members of the Chironomidae, Daphnidae/Chydoridae, Acarina, Porifera (Ephydatia mülleri and Spongilla lacustris), Bryozoa (Cristatella mucedo and Plumatella spp.) and Charophyta (Chara sp.). Of the chironomids, the genus Chironomus was present in the oldest lacustrine layers of all four lakes, but other genera recorded at the marine/lacustrine boundary were Dicrotendipes, Procladius (?), Einfeldia, Microtendipes, and Glyptotendipes. Remains of the caddis fly family Limnephilidae were also present in the earliest lacustrine sediments in Kvennavatnet and Kvernavatnet. The oldest invertebrate fauna is typical for mesotrophic lakes. However, chironomids and mites have been present in this area from at least about 10 500 years B.P. A diverse chironomid community was established between 300 and 800 years after isolation from the sea at Kvernavatnet on the island of Hitra, while only between 80 and 120 years passed before a comparably diverse community developed at Kvennavatnet on the mainland coast. A similar development of the invertebrate fauna occurred in Kvennavatnet, Kvernavatnet and Storkuvatnet. However, Litjvatnet deviates greatly from the ‘normal’ pattern because a tsunami disturbed the bottom sediments and fauna. The tsunami, a gigantic sea wave, was caused by a submarine slide from the Norwegian continental slope. It reached Litjvatnet, today located 24 m a.s.l., but was not traced in Storkuvatnet at 30 m a.s.l. This event happened about 7200 years B.P.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007934825272
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  • 4
    Electronic Resource
    Electronic Resource
    Evolution of novel metabolic pathways for the degradation of chloroaromatic compounds (1997)
    Springer
    Antonie van Leeuwenhoek 71 (1997), S. 159-178 
    Details
    ISSN: 1572-9699
    Keywords: aromatic pathways ; chlorobenzenes ; evolution ; genes ; plasmids ; pseudomonas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Chlorobenzenes are substrates not easily metabolized by existing bacteria in the environment. Specific strains, however, have been isolated from polluted environments or in laboratory selection procedures that use chlorobenzenes as their sole carbon and energy source. Genetic analysis indicated that these bacteria have acquired a novel combination of previously existing genes. One of these gene clusters contains the genes for an aromatic ring dioxy-genase and a dihydrodiol dehydrogenase. The other contains the genes for a chlorocatechol oxidative pathway. Comparison of such gene clusters with those from other aromatics degrading bacteria reveals that this process of recombining or assembly of existing genetic material must have occurred in many of them. Similarities of gene functions between pathways suggest that incorporation of existing genetic material has been the most important mechanism of expanding a metabolic pathway. Only in a few cases a horizontal expansion, that is acqui sition of gene functions to accomodate a wider range of substrates which are then all transformed in one central pathway, is observed on the genetic level. Evidence is presented indicating that the assembly process may trigger a faster divergence of nearby gene sequences. Further ‘fine-tuning’, for example by developing a proper regulation, is then the next step in the adaptation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1000166400935
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  • 5
    Electronic Resource
    Electronic Resource
    Evolution of bacterial genomes (1997)
    Springer
    Antonie van Leeuwenhoek 71 (1997), S. 265-270 
    Details
    ISSN: 1572-9699
    Keywords: bacteria ; DNA ; evolution ; genome ; RNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This review examines evolution of bacterial genomes with an emphasis on RNA based life, the transition to functional DNA and small evolving genomes (possibly plasmids) that led to larger, functional bacterial genomes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1000123216769
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  • 6
    Electronic Resource
    Electronic Resource
    Bacterial evolution and metabolism (1997)
    Springer
    Antonie van Leeuwenhoek 71 (1997), S. 257-263 
    Details
    ISSN: 1572-9699
    Keywords: bacteria ; energy ; evolution ; genome ; metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This article examines the relationship between (or dependence of) bacterial evolution in prokaryotes and metabolism, and the changing physical-chemical conditions present during early evolution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1000175217677
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  • 7
    Electronic Resource
    Electronic Resource
    Molecular evolution in bacteria: Surfaces, cathodes and anodes (1997)
    Springer
    Antonie van Leeuwenhoek 71 (1997), S. 363-368 
    Details
    ISSN: 1572-9699
    Keywords: assembly ; anode ; bacteria ; cathode ; DNA ; evolution ; genetics ; molecular ; surfaces
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Molecular evolution is examined in bacteria with an emphasis on mineral surfaces, membranes, cathodes and anodes. In early molecular evolution, cathode-anode system may have been naturally occurring on a nm to µm scale. Secondly, the cathode-anode system could have been separated by a primitive, permeable lipid or microsphere on a mineral surface, that was a precursor of a more advanced membrane with a charge differential on either side of the membrane. These aspects will be considered from a theoretical evolutionary perspective.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1000271219036
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  • 8
    Electronic Resource
    Electronic Resource
    Molecular evolution and optimization (1997)
    Springer
    Antonie van Leeuwenhoek 72 (1997), S. 251-259 
    Details
    ISSN: 1572-9699
    Keywords: bacteria ; catalysis ; DNA ; enzyme ; evolution ; microorganisms ; optimization ; RNA ; time
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Microbial populations (and life) not only evolve, they optimize. The transition from a random, unorganized, lifeless Earth to the present situation, where the Earth is virtually covered with nucleic acids and diverse and complex species, required numerous molecular changes and the integration of metabolic pathways over billions of years. Primitive prokaryotic life was dependent on and constrained by the physical-chemical conditions on the Earth, while slowly reshaping conditions present. In this review, molecular evolution and molecular optimization are examined with an emphasis on the order in which evolutionary events occurred.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1000456825081
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  • 9
    Electronic Resource
    Electronic Resource
    The Glycophorin A Gene Family in Gorillas: Structure, Expression, and Comparison with the Human and Chimpanzee Homologues (1997)
    Springer
    Biochemical genetics 35 (1997), S. 59-76 
    Details
    ISSN: 1573-4927
    Keywords: glycophorins ; gorilla ; evolution ; gene family ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Homologues of MN blood group antigens, encoded by members of the glycophorin A (GPA) gene family, are expressed in man, anthropoid apes, and some species of Old World monkeys. Previous studies had shown that a three-gene framework, most closely related to that in man, is present in the chimpanzee. Here we report the genomic structure, transcript map, and protein expression of the GYPA locus in gorillas. Compared to the corresponding human and chimpanzee homologues, gorilla GPA, GPB, and GPB/E genes each showed a high degree of sequence identity, with the same exon-intron organization. However, the expression of exons III, IV, or V encoding the extracellular or membrane domains of homologous glycophorins varied among the three species. Gorilla GPA and GPB/E genes were unique in that the former occurred in two allelic forms with or without the expression of exon III, whereas the latter contained one (ψ exon III) instead of two silenced exons (ψ exons III and IV). Differences from human but not chimpanzee GPA also included the presence of a hybrid M/N epitope and the absence of the sequon for N-glycosylation. Owing to the retention of a functional exon III, gorilla GPB was more similar to chimpanzee GPB than human GPB. A transspecies allele was identified in the gorilla that gave rise to the Henshaw (He)-like antigen similar to that found in man. These results provide further insight into the model for evolution of the GPA gene family, indicating that the mechanisms underlying inter- and intraspecific polymorphism of glycophorins could predate the divergence of gorillas as the consequence of gene duplication and diversification.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022212630370
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  • 10
    Electronic Resource
    Electronic Resource
    Multiple Functions for Secondary Metabolites in Encrusting Marine Invertebrates (1997)
    Springer
    Journal of chemical ecology 23 (1997), S. 1527-1547 
    Details
    ISSN: 1573-1561
    Keywords: Secondary metabolites ; chemical defense ; evolution ; ascidians ; sponges
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We used three chemical fractions (spanning a wide range of polarities) from the extracts of four marine invertebrates, the spongesCrambe crambe andHemimycale columella and the ascidiansCystodytes dellechiajei andPolysyncraton lacazei, to test inhibition of cell division, photosynthesis, and settlement. We used assay organisms from the same habitat, seeking to determine whether a species may display diverse, ecologically relevant bioac-tivities and, if so, whether the same types of compound may be responsible for such activities. Cell division was strongly inhibited by the spongeC. crambe. A dichloromethane fraction fromC. crambe prevented development of sea urchinParacentrotus lividus eggs at a concentration of 10 μg/ml, as did the butanolic fraction, but at higher concentrations (50 and 100 μg/ml). At 50 μg/ml, the aqueous fraction ofC. crambe allowed cell division but prevented eggs from developing beyond the gastrula stage. Similar results were recorded with the dichloromethane fraction ofP. lacazei and from the aqueous fraction ofH. columella. Photosynthesis was unaffected by any of the species at 50 μg/ml. Larval settlement was inhibited by one or another fraction from the four species surveyed at a concentration of 50 μg/ml, althoughC. crambe exhibited the greatest amount of activity. We therefore found that various fractions displayed the same type of bioactivity, while compounds from the same fraction were responsible for multiple activities, suggesting that secondary metabolites are multiple-purpose tools in nature, which is relevant to our understanding of species ecology and evolution. Moreover, results showed that the assessment of the role of chemical compounds is significantly influenced by the assay organism, fractionation procedure, concentration, and duration of experiments. All these factors should be carefully considered when testing ecological hypotheses of the roles of chemically-mediated bioactivities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/B:JOEC.0000006420.04002.2e
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  • 11
    Electronic Resource
    Electronic Resource
    Revision ofDoniophyton (Compositae, Barnadesioideae) (1997)
    Springer
    Plant systematics and evolution 206 (1997), S. 33-45 
    Details
    ISSN: 1615-6110
    Keywords: Compositae ; Barnadesioideae ; Doniophyton ; Chuquiraga ; Argentina ; Chile ; evolution ; systematics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This revision describes, illustrates and documents morphological variation inDoniophyton (Compositae, Barnadesioideae), restricted to Argentina and Chile. Two species are recognized,D. anomalum andD. weddellii (sp. nova), possessing distinct morphological and chromosomal features, elevational tolerances, and nearly allopatric distributions.Doniophyton weddellii occurs primarily in central to northern Andean Chile and Argentina from 1900–4000 m a. s. l.;D. anomalum is found principally in centralwestern Argentina and south into Patagonia at 0–1800 m a. s. l. Close relationship exists withChuquiraga of subfam.Barnadesioideae. It is hypothesized thatDoniophyton evolved out ofChuquiraga in the high central Andes between Chile and Argentina. It is suggested thatD. weddellii differentiated first, correlating with an aneuploid chromosomal decrease from n = 27 (inChuquiraga) to n = 25. Further evolution and chromosomal decrease to n = 24 resulted inD. anomalum, with accompanying migration into southern Andes and Patagonia. Nomenclatural changes result from examination of protologues and type specimens:Doniophyton anomalum replaces the commonly used nameD. patagonicum, and a new species,D. weddellii, is described for the taxon masquerading under the routinely used superfluous nameD. andicola.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00987939
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  • 12
    Electronic Resource
    Electronic Resource
    “Just-so” stories about “inner cognitive Africa”: some doubts about Sorensen's evolutionary epistemology of thought experiments (1997)
    Springer
    Biology and philosophy 12 (1997), S. 207-224 
    Details
    ISSN: 1572-8404
    Keywords: evolution ; epistemology ; evolutionary epistemology ; naturalized epistemology ; thought experiments ; modality ; utility ; fitness ; adaptation ; reliability ; possible worlds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract Roy Sorensen advances an evolutionary explanation of our capacity for thought experiments which doubles as a naturalized epistemological justification. I argue Sorensen”s explanation fails to satisfy key elements of environmental-selectionist explanations and so fails to carry epistemic force. I then argue that even if Sorensen succeeds in showing the adaptive utility of our capacity, he still fails to establish its reliability and hence epistemic utility. I conclude Sorensen”s account comes to little more than a “just-so story”.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1017986908266
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  • 13
    Electronic Resource
    Electronic Resource
    Taking the ‘Error’ Out of Ruse‘s Error Theory (1997)
    Springer
    Biology and philosophy 12 (1997), S. 385-397 
    Details
    ISSN: 1572-8404
    Keywords: morality ; evolution ; error theory
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract Michael Ruse‘s Darwinian metaethics has come under just criticism from Peter Woolcock (1993). But with modification it remains defensible. Ruse (1986) holds that people ordinarily have a false belief that there are objective moral obligations. He argues that the evolutionary story should be taken as an error theory, i.e., as a theory which explains the belief that there are obligations as arising from non-rational causes, rather than from inference or evidential reasons. Woolcock quite rightly objects that this position entails moral nihilism. However, I argue here that people generally have justified true beliefs about which acts promote their most coherent set of moral values, and hence, by definition, about which acts are right. What the evolutionary story explains is the existence of these values, but it is not an error theory for moral beliefs. Ordinary beliefs correspond to real moral properties, though these are not objective or absolute properties independent of anyone‘s subjective states. On its best footing, therefore, a Darwinian metaethics of the type Ruse offers is not an error theory and does not entail moral nihilism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006577007049
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  • 14
    Electronic Resource
    Electronic Resource
    Evolution of the Sacoglossa (Mollusca, Opisthobranchia) and the ecological associations with their food plants (1997)
    Springer
    Evolutionary ecology 11 (1997), S. 301-335 
    Details
    ISSN: 1573-8477
    Keywords: ecological associations ; evolution ; integrative biology ; Opisthobranchia ; resource tracking ; Sacoglossa ; Ulvophyceae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Evolution in the opisthobranch order Sacoglossa has been closely linked to their specialized suctorial herbivorous habits. All shelled Sacoglossa (about 20% of the species) feed on one algal genus, Caulerpa. The non-shelled Sacoglossa have 'radiated' to other diets, mainly siphonalean or septate green algae (Class Ulvophyceae). Comparing the phylogeny of sacoglossan genera with the phylogeny of the Ulvophyceae indicates that co-speciation may have taken place at the basal node of the Sacoglossa, and that host switching has taken place several times in the two non-shelled clades. It is suggested that the most important evolutionary process has been speciation by 'resource-tracking'; the resource tracked is most probably cell wall composition of the algal prey. The fossil record of extant sacoglossan genera dates back to the Eocene and, based on the fossil record of siphonalean green algae, the Sacoglossa most likely appeared in the Cretaceous. It is hypothesized that the ancestral sacoglossan was epifaunal, suctorial and herbivorous, and the 'ancestral' food plant was not Caulerpa, but filamentous, calcified, now extinct, Udoteaceae.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018468420368
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  • 15
    Electronic Resource
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    The evolution of dispersal in a two-patch system:Some consequences of differences between migrants and residents (1997)
    Springer
    Evolutionary ecology 11 (1997), S. 613-629 
    Details
    ISSN: 1573-8477
    Keywords: dispersal ; evolution ; evolutionarily stable strategy ; migrant ; resident ; survival
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We investigate how age-structure and differences in certain demographic traits between residents and immigrants of a single species act to determine the evolutionarily stable dispersal strategy in a two-patch environment that is heterogeneous in space but constant in time. These two factors have been neglected in previous models of the evolution of dispersal, which generally consider organisms with very simple life-cycles and assume that, whatever their origin, individuals in a given habitat have the same bio-demographic characteristics. However, there is increasing empirical evidence that dispersing individuals have different demographic properties from phylopatric ones. We develop a matrix model in which recruitment depends on local population densities. We assume that dispersal entails a proportional cost to immigrant fecundity, which can be compensated by differences in survival rates between immigrants and residents. The evolutionarily stable strategies (ESS) for dispersal are identified using a combination of analytical expressions and numerical simulations. Our results show that philopatry is selected (1) when dispersal rates do not vary in space, (2) when the metapopulation is a source-sink system and (3) when dispersal rates vary in space (asymmetric dispersal) and immigrants do not compensate for their reduced fecundity. We observe that non-zero asymmetric dispersal rates may be evolutionarily stable when (1) immigrants and residents are demographically alike and (2) immigrants compensate totally for their reduced fecundity through an increase in adult survival. Under these conditions, we find that the ESS occurs when the fitnesses at equilibrium in the two habitats, measured in our model by the realized reproductive rates, are each equal to unity. A comparison with previous studies suggests a unifying rule for the evolution of dispersal: the dispersal rates which permit the spatial homogenization of fitnesses are ESSs. This condition provides new insight into the evolutionary stability of source-sink systems. It also supports the hypothesis that immigrants have adapted demographic strategies, rather than the hypothesis that dispersal is costly and immigrants are at a disavantage compared with residents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s10682-997-1516-z
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  • 16
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    Tree-thinking and nemertean systematics, with a systematization of the Eureptantia (1997)
    Springer
    Hydrobiologia 365 (1997), S. 33-46 
    Details
    ISSN: 1573-5117
    Keywords: Phylogeny ; cladistics ; taxonomy ; systematics ; classification ; evolution ; history ; chronicle ; Nemertea ; Hoplonemertea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract I review how some influential nemertean systematistshave perceived and illustrated phylogenetic trees andargue that the nineteenth century nemerteantaxonomists still influence many contemporarynemertean taxonomists to a high degree. By showing hownineteenth century systematics differs from moremodern views on trees, I hope to convey the advantagesof a cladistic approach to tree-thinking and nemerteansystematics. Furthermore I propose a systematizationof the Eureptantia that illustrates the cladisticapproach to tree-thinking but, more importantly, isalso a better representation of eureptantic phylogenythan previous classifications.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003174326275
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  • 17
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    No Evidence for a Y Chromosomal Effect on Alternative Behavioral Strategies in Mice (1997)
    Springer
    Behavior genetics 27 (1997), S. 477-482 
    Details
    ISSN: 1573-3297
    Keywords: Aggression ; nest-building behavior ; wild house mice ; behavioral strategies ; bidirectional selection ; Y chromosome ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract This study takes the first step toward testing a Y chromosomal effect on both aggression and thermoregulatory nest-building behavior in mouse lines either bidirecrionally selected for short (SAL) and long (LAL) attack latency or high (HIGH) and low (LOW) nest-building behavior. Using reciprocal crosses between SAL and LAL, and between HIGH and LOW, we found no indications for Y chromosomal effects on thermoregulatory nest-building behavior. As for aggression, we confirmed earlier studies on SAL and LAL, i.e., the origin of the Y chromosome influences attack latency, i.e., aggression. However, we did not find indications for a Y chromosomal effect on aggression in the HIGH and LOW lines. Since aggression and nest-building behavior have been shown to be characteristic parameters of two fundamentally different behavioral strategies, the present data underline the improbability of Y chromosomal genes underlying the genetic architecture of alternative behavioral strategies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1025678517986
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  • 18
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    Comparative mapping of Xp22 genes in hominoids – evolutionary linear instability of their Y homologues (1997)
    Springer
    Chromosome research 5 (1997), S. 167-176 
    Details
    ISSN: 1573-6849
    Keywords: comparative mapping ; evolution ; hominoids ; X–Y homologous genes ; Y chromosome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Several genes located within or proximal to the human PAR in Xp22 have homologues on the Y chromosome and escape, or partly escape, inactivation. To study the evolution of Xp22 genes and their Y homologues, we applied multicolour fluorescence in situ hybridization (FISH) to comparatively map DNA probes for the genes ANT3, XG, ARSD, ARSE (CDPX), PRK, STS, KAL and AMEL to prometaphase chromosomes of the human species and hominoid apes. We demonstrate that the genes residing proximal to the PAR have a highly conserved order on the higher primate X chromosomes but show considerable rearrangements on the Y chromosomes of hominoids. These rearrangements cannot be traced back to a simple model involving only a single or a few evolutionary events. The linear instability of the Y chromosomes gives some insight into the evolutionary isolation of large parts of the Y chromosomes and thus might reflect the isolated evolutionary history of the primate species over millions of years.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018490713273
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  • 19
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    Comparative analysis on the distribution of heterochromatin in Citrus, Poncirus and Fortunella chromosomes (1997)
    Springer
    Chromosome research 5 (1997), S. 86-92 
    Details
    ISSN: 1573-6849
    Keywords: chromosome banding ; citrus ; fluorochrome ; heterochromatin ; karyotype ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Double fluorochrome staining with chromomycin A3 (CMA) and 4′-6-diamidino-2-phenylindole (DAPI) was used to characterize and compare the distribution of constitutive heterochromatin along chromosomes of Citrus, Poncirus and Fortunella species. Only CMA-positive bands were distinguishable in metaphase chromosomes. Preferential distribution of heterochromatin in terminal regions, mainly of the long arm, and centromeric regions of a few long chromosomes was a common feature of these genera. Heteromorphism between possible homologous chromosomes was present in the majority of species. Citrus and Poncirus revealed some remarkably uniform chromosomes without any intensively fluorescing region, whereas Fortunella cultivars were differentiated by the presence of CMA bands in all chromosomes. Through measurements assisted by a computer, amounts of CMA-positive regions were shown to be highest in Fortunella. Similarities between Citrus and Poncirus suggest little heterochromatin diversification among karyotypes of these genera, whereas Fortunella, with higher amounts and more homogenous distribution of heterochromatin, is more divergent.
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    Male-biased distribution of the human Y chromosomal genes SRY and ZFY in the lizard Calotes versicolor, which lacks sex chromosomes and temperature-dependent sex determination (1997)
    Springer
    Chromosome research 5 (1997), S. 413-419 
    Details
    ISSN: 1573-6849
    Keywords: evolution ; reptiles ; sex determination ; SRY ; ZFY
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the present investigation on the lizard Calotes versicolor, which lacks temperature-dependent sex determination, all the conventional cytological techniques used failed to resolve a distinguishable pair of sex chromosomes. However, probing of the genome with the human Y-linked genes SRY and ZFY showed sex-specific bias in their distribution. While the SRY probe hybridized to all the males, more than half of the females examined did not show any hybridization. ZFY hybridized to both the sexes, giving two bands; one was common to all the individuals of both sexes, but the other, of the lower molecular length, occurred in all the males but in less than 50% of females. This predominantly male-specific band is named AMF. The SRY-positive females were also positive for the AMF of ZFY. As positive as well as negative females were fertile and none of the males lacked SRY, it appears that SRY is essential for males only and that both the genes are syntenic in this species. This report raises interesting possibilities on the differentiation of the sex chromosomes in C. versicolor and evolution of SRY/ZFY on the Y chromosome of eutherian mammals through the ancestral group(s) that harbour sex-independent SRY- and ZFY-related genes.
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    URL: http://dx.doi.org/10.1023/A:1018452526903
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    Rice genetic resources: history, conservation, investigative characterization and use in Japan (1997)
    Springer
    Plant molecular biology 35 (1997), S. 69-77 
    Details
    ISSN: 1573-5028
    Keywords: rice ; wild rice ; Oryza spp. ; evolution ; conservation ; evaluation ; utilization ; germplasm ; genetic resources ; genebank
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Rice has been grown in Japan for about 3000 years. Although both japonica and indica varieties have been grown in Japan, now japonica rices are grown. Japanese rice breeding has used an ecological breeding approach. While emphasis in rice breeding in the 1940's and 1950's focussed on yield in recent decades quality has been of major importance. Consumer preference and name recognition of high quality varieties, such as Koshihikari, has resulted in slow acceptance of new varieties. Rice germplasm was systematically collected throughout Japan between 1962 and 1963. Subsequent acquisition and collecting, in Japan and other countries, has resulted in 28,000 accessions being conserved in the National Genebank, based at the National institute of Agrobiological Resources (NIAR). Research on genetic diversity of rice using a range of techniques, for example esterase isozymes, has revealed clinal variation in rice radiating from the center of diversity of rice in and around southwest China. Newly found genes in traditional rice germplasm, such as genes for non-elongating mesocotyl, are now routinely identified on the rice genome. Pioneering studies on eco-genetic differentiation of species in the genus Oryza in Japan has revealed much about the complex genepool for which rice evolved. Pest and disease resistance sources, particularly to blast, bacterial blight and brown plant hopper, from many countries have been incorporated into Japanese varieties. Cold tolerance at the booting stage was found in the Indonesian variety Silewah. In the future in characterisation of rice germplasm and interaction between rice germplasm specialists and rice molecular scientists, both in Japan and internationally, will be corner stones to securing rice genetic diversity and rice improvement in the next century.
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    URL: http://dx.doi.org/10.1023/A:1005784431759
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    Analysis of multiple copies of geminiviral DNA in the genome of four closely related Nicotiana species suggest a unique integration event (1997)
    Springer
    Plant molecular biology 35 (1997), S. 313-321 
    Details
    ISSN: 1573-5028
    Keywords: integration ; geminivirus ; plant genomes ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Previously, we discovered multiple direct repeats of geminivirus-related DNA (GRD) sequences clustered at a single chromosomal position in Nicotiana tabacum (tobacco). Here we show that, in addition to tobacco, multiple copies of these elements occur in the genomes of three related Nicotiana species, all in the section Tomentosae: N. tomentosiformis, N. tomentosa and N. kawakamii, but not in 9 other more distantly related Nicotiana species, nor in various other solanaceous and non-solanaecous plants. DNA sequence analysis of 18 GRD copies reveal 4 distinct, but highly related, sub-families: GRD5, GRD3 and GRD53 in tobacco; GRD5 in N. tomentosiformis and N. kawakamii; and GRD2 in N. tomentosa. In addition to novel sequences, all elements share significant but varying lengths of DNA sequence similarity with the geminiviral replication origin plus the adjacent rep gene. There is extended sequence similarity to REP protein at the deduced amino acid sequence level, including motifs associated with other rolling circle replication proteins. Our data suggest that all GRD elements descend from a unique geminiviral integration event, most likely in a common ancestor of these Tomentosae species.
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    URL: http://dx.doi.org/10.1023/A:1005885200550
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    Mitochondrial Dehydrogenases in Different Taxa of Tetrahymena: Effect of Insulin (1997)
    Springer
    Bioscience reports 17 (1997), S. 529-535 
    Details
    ISSN: 1573-4935
    Keywords: Mitochondria ; mt-dehydrogenase ; evolution ; insulin ; hormonal effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Mitochondrial dehydrogenase activity was measured in seven taxa of Tetrahymena (T. pyriformis G1, T. hegewishi, T. malaccensis, T. pigmentosa, T. shapiro, T. thermophila CU-399, T. thermophila MS-1). Enzyme activity was different in the taxa investigated. Insulin reduced enzyme activity in six of the seven taxa studied. The duration of activity reduction was relatively long (5–10 min.) in most of the cases, and in T. hegewishi this lasted up to the end of the measurements (30 min.). There was no interrelation between the basic dehydrogenase activity of the taxon and the effect of insulin. There was also no correlation between the degree of relationship (of the taxa) and the dehydrogenase profile after insulin treatment.
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    URL: http://dx.doi.org/10.1023/A:1027308223168
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    Imprinting Effects of Proline Containing Dipeptides (Proline-Glycine, Proline-Leucine, Proline-Valine and Their Retro Variants) in Tetrahymena. Evolutionary Conclusions (1997)
    Springer
    Bioscience reports 17 (1997), S. 537-542 
    Details
    ISSN: 1573-4935
    Keywords: Tetrahymena ; evolution ; hormones ; peptides ; signal molecule ; imprinting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Proline-glycine, proline-leucine and proline-valine dipeptides and their retro variants were used in the experiments to study the effects of pretreatment (imprinting) in Tetrahymena, by investigating fluorescein isothiocyanate (FITC)-conjugated peptide binding. The protozoan organism could differentiate between the proline-dipeptides containing different partner amino-acids and between the dipeptides having the amino acids in reversed positions. The effect of imprinting was positive or negative and this was dependent on the type of the partner amino acid and on its position. Pro-Gly and Pro-Leu induced positive imprinting (elevated FITC-dipeptide binding) and Pro-Val induced negative imprinting (decrease of FITC-peptide binding). There was positive imprinting induction in two cases for the retro FITC-peptide and in one case for the FITC-conjugate of the imprinter peptide itself. The highest positive imprinting (almost 60% increase) was induced by Pro-Gly for FITC-Gly-Pro. Considering earlier—chemotaxis—experiments, the results of the present—binding—studies run parallel with the physiological effects. The experiments call attention to the sharp differentiating ability of small peptides at a unicellular level, that could have some role in the selection of molecules for hormone formation, during evolution.
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    URL: http://dx.doi.org/10.1023/A:1027360207238
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    Modification of Clay Forms by Tufted Capuchins (Cebus apella) (1997)
    Springer
    International journal of primatology 18 (1997), S. 455-467 
    Details
    ISSN: 1573-8604
    Keywords: Cebus ; Homo ; evolution ; Paleolithic art ; tool-use
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We examined modification of clay forms by tufted capuchins (Cebus apella) by presenting groups of subjects with clay, paint, stones, leaves, and sticks. In Experiment 1, 7 of 10 subjects reshaped portable forms with their hands and with stones, and decorated them with leaves and paint. In Experiment 2, 9 subjects marked clay slabs manually and with stick and stone tools. The manipulative propensities of Cebus can help us to understand psychological processes that underlie artistic expression in Homo and Pan.
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    URL: http://dx.doi.org/10.1023/A:1026394618857
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    To mark the host or the patch: Decisions of a parasitoid searching for concealed host larvae (1997)
    Springer
    Evolutionary ecology 11 (1997), S. 145-168 
    Details
    ISSN: 1573-8477
    Keywords: evolution ; Halticoptera laevigata ; host-marking pheromone ; parasitoids ; patch mark ; Tephritidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We found evidence for patch marking in the parasitic wasp Halticoptera laevigata (Hymenoptera: Pteromalidae) foraging for concealed hosts. Wasps attack larvae of the fruit fly Myoleja lucida (Diptera: Tephritidae) in fruits of honeysuckle. A special feature of this host-parasitoid system is the limited food supply of a patch (i.e. a fruit of honeysuckle), which allows the successful development of only a single host fly larva. Females of the parasitoid H. laevigata were found to mark the host patch with a pheromone and to abandon the patch following oviposition into a single host larva. Field data revealed that eggs of the parasitoid were spread out evenly among infested patches, with several larvae of the host fly left unparasitized in those patches that contained more than one host. Since many parasitic insects mark the parasitized host after oviposition, we assumed host marking to be the ancestral character state and studied the patch-marking behaviour of H. laevigata as a derived character state as an alternative foraging strategy. We used stochastic dynamic modelling to investigate under what conditions mutant (patch) markers would be able to invade a population of normal (larval) markers. The models suggested that, under a variety of conditions, wasps marking the patch obtained higher fitness than wasps only marking the larva. Consequently, the results from our model predict the evolution of the patch-marking behaviour found in the empirical investigation. Finally, we discuss alternative pathways to the evolution of patch marking and point out under what circumstances the evolution of a patch-marking behaviour can generally be expected.
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    URL: http://dx.doi.org/10.1023/A:1018495731755
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    Evolution of flower shape inVeroniceae (Scrophulariaceae) (1997)
    Springer
    Plant systematics and evolution 205 (1997), S. 1-25 
    Details
    ISSN: 1615-6110
    Keywords: Veroniceae ; Scrophulariaceae ; Flower shape ; flower development ; quantitative developmental character ; phylogeny ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Floral evolution in the tribeVeroniceae was examined using phylogenetic analysis combining 24 adult morphology and chromosome number characters with 22 qualitative and quantitative floral development characters. Taxa sampled included nine species ofVeroniceae and as an outgroup one species each ofDigitaleae andVerbasceae. Veronica, Besseya, andSynthyris formed one clade, subtended byPseudolysimachion and then by theHebe group;Veronicastrum orWulfenia represent the basal-most branch of the tribe. The ancestral flowers of theVeroniceae may have been small with moderately short corolla tubes and lobes; long corolla tubes arose four times in the tribe and large corolla lobes twice.
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    URL: http://dx.doi.org/10.1007/BF00982795
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    Floral divergence and convergence in the genusPelargonium (Geraniaceae) in southern Africa: Ecological and evolutionary considerations (1997)
    Springer
    Plant systematics and evolution 208 (1997), S. 71-97 
    Details
    ISSN: 1615-6110
    Keywords: Geraniaceae ; Pelargonium ; Bees ; beeflies ; birds ; butterflies ; long-proboscid flies ; convergence ; evolution ; floral ecology ; pollination ; pollination guilds ; pollination syndromes ; Southern Africa
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Based on field observations and a survey of the available literature, the functional and evolutionary significance of floral characters ofPelargonium is investigated in relation to a recent infrageneric re-classification. Most of the 208Pelargonium taxa (recognized as species, subspecies or varieties) involved show bee and long-proboscid hovering fly pollination syndromes (about 60% and 25%, respectively), only 7% of the taxa are pollinated by butterflies, some 2 to 4% by hawkmoths and presumably 1% by birds. The heterogeneity ofPelargonium in terms of structural blossom types and pollination syndromes indicates an independent and repeated evolution of convergent flower morphs in the genus and even in sections.
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    URL: http://dx.doi.org/10.1007/BF00986083
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    Hybridization and evolution inCardamine (Brassicaceae) at Urnerboden, Central Switzerland: Biosystematic and molecular evidence (1997)
    Springer
    Plant systematics and evolution 204 (1997), S. 233-256 
    Details
    ISSN: 1615-6110
    Keywords: Brassicaceae ; Cardamine amara ; C. ×insueta ; C. rivularis ; C. schulzii ; Hybridization ; evolution ; amphiploidy ; introgression ; cpDNA ; isozymes ; RAPD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Hybridization between two diploid (2n = 2x = 16) species ofBrassicaceae, Cardamine rivularis andC. amara, at Urnerboden, Central Switzerland, resulted in the rather unusual triploid hybridC. insueta (2n = 3x = 24), and later on in the amphiploidC. schulzii (2n = 6x = 48). The hybrid and the neopolyploid species colonized successfully some man-made biotopes. Plants ofC. insueta are mostly functional females with non-dehiscent anthers, but true hermaphrodite individuals with partly sterile pollen grains also occur within the population. Analyses of cpDNA and nuclear DNA permitted to establish the parentage of the hybrid: the maternal parent which contributed unreduced egg cells proved to beC. rivularis whereas the normally reduced pollen originated fromC. amara. The pronounced genetic variability inC. insueta revealed by isozyme and RAPD analyses, at variance with the polarized segregation, heterogamy and strong vegetative reproduction of the hybrid, is possibly influenced by recurrent formation ofC. insueta which party results from backcrosses betweenC. insueta andC. rivularis but may also proceed by other pathways. The amphiploidCardamine schulzii has normally developed anthers but its pollen is sometimes highly sterile. The surprisingly uniform genetic make-up of the new amphiploid species might be related to its possible monotopic origin and/or young phylogenetic age but should be further assessed. Site management seems to be very important to a further development of hybridogenous populations and their parent species. In conclusion, the evolution at Urnerboden is discussed in the context of the traditional concept of multiple plant origins.
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    URL: http://dx.doi.org/10.1007/BF00989208
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    Fruit component analysis of south Pacific coconut palm populations (1997)
    Springer
    Genetic resources and crop evolution 44 (1997), S. 327-335 
    Details
    ISSN: 1573-5109
    Keywords: Cocos nucifera ; diversity ; evolution ; germplasm ; genetic resources ; morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The south Pacific region contains a large genetic resource for the genetic improvement of coconut palms (Cocos nucifera L.). A study of the diversity in the species was made during 1992/3 using fruit component analysis on a representative sample from 29 distinct south Pacific populations in order to characterise the germplasm present in the region. A large diversity in fruit morphology was found that ranged from populations exhibiting wild-type characters in central Pacific to populations displaying domesticated characteristics in Rennell Island, the Sikaiana Islands, the Marquesas Islands, and in Papua New Guinea. Many populations exhibited fruit characteristics intermediate between the two, which were thought to have arisen due to introgressive hybridisation between the wild and domesticated populations. Continuous variation in fruit morphology was found in these populations, and cluster analysis arbitrarily divided the continuum into discrete groups which were consistent with geographic affinities. Groups were defined in Melanesia, Western Polynesia and Eastern Polynesia. The continuum displayed clinal variation from populations with small fruit and low husk content in the west to large fruit and more husk in the east of the region. The wild and domesticated populations were found in disjunct pockets throughout the area, and did not form part of the clines. Most populations consisted of a wide range of fruit morphology, from individuals expressing wild-type characters to those with domestic-type characters. The occurrence of both wild and domesticated populations within the clinal variation indicates that further exploration should be made to determine the presence of other potentially useful populations. While this activity is proceeding, collection and conservation can proceed using the classification already defined.
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    URL: http://dx.doi.org/10.1023/A:1008652618350
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    Phylogeny of the Acipenseriformes: cytogenetic and molecular approaches (1997)
    Springer
    Environmental biology of fishes 48 (1997), S. 127-155 
    Details
    ISSN: 1573-5133
    Keywords: sturgeon ; paddlefish ; Huso ; Acipenser ; Scaphirhynchus ; Pseudoscaphirhynchus ; Polyodon ; Psephurus ; karyotype ; chromosome ; macrochromosome ; microchromosome ; genome ; DNA content ; 18S rRNA gene ; cytochrome ; 12S mtrRNA gene ; 16s mtrRNA gene ; rate of molecular evolution ; phylogeny ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The review of the data on karyology and DNA content in Acipenseriformes shows that both extant families, the Polyodontidae and Acipenseridae, originated from a tetraploid ancestor which probably had a karyotype consisting of 120 macro- and microchromosomes and DNA content of about 3.2–3.8 pg per nucleus. The tetraploidization of the presumed 60-chromosome ancestor seems to have occurred at an early time of evolution of the group. The divergence of the Acipenseridae into Scaphirhyninae and Acipenserinae occurred without polyploidization. Within the genus Acipenser, polyploidization was one of the main genetic mechanisms of speciation by which 8n and 16n-ploid species were formed. Individual gene trees constructed for sequenced partial fragments of the 18S rRNA (230 base pairs, bp), 12S rRNA (185 bp), 16S rRNA (316 bp), and cytochrome b (270 bp) genes of two Eurasian (A. baerii and A. ruthenus) and two American (A. transmontanus and A. medirostris) species of Acipenser, Huso dauricus, Pseudoscaphirhynchus kaufmanni, Scaphirhynchus albus, and Polyodon spathula showed a low level of resolution; the analysis of a combined set of data for the four genes, however, gave better resolution. Our phylogeny based on molecular analysis had two major departures from existing morphological hypotheses: Huso dauricus is a sister-species to Acipenser instead of being basal to all acipenseriforms, and Scaphirhynchus and Pseudoscaphirhynchus do not form a monophyletic group. The phylogenetic tree constructed for the cytochrome b gene fragments (with inclusion of 7 additional species of Acipenser) supported the conclusion that octoploid species appeared at least three times within Acipenser.
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    Biopolitics: the newest synthesis? (1997)
    Springer
    Genetica 99 (1997), S. 173-184 
    Details
    ISSN: 1573-6857
    Keywords: evolution ; genetics ; neurophysiology ; philosophy ; politics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract On first impression, the disciplines of genetics and political science would appear to be unrelated. And yet, commencing more than 30 years ago, the interdisciplinary field known as Biopolitics has now taken hold. This essay traces the central thrust of the biopolitical research agenda. It describes, analyzes, and assesses how political scientists have sought to show connections between our species' genetic constitution and our species' political behavior. Important bridges between the two are the neurophysiology of the human brain and the role of evolutionary theory in charting man's adaptational political profile. The parameters of the emerging biopolitical literature raise profound policy questions, some of which are also characterized.
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    URL: http://dx.doi.org/10.1023/A:1018381714851
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    Evolutionary links between telomeres and transposable elements (1997)
    Springer
    Genetica 100 (1997), S. 73-84 
    Details
    ISSN: 1573-6857
    Keywords: evolution ; heterochromatin ; retrotransposable elements ; telomerase ; telomeres
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Transposable elements are abundant in the genomes of higher organisms but are usually thought to affect cells only incidentally, by transposing in or near a gene and influencing its expression. Telomeres of Drosophila chromosomes are maintained by two non-LTR retrotransposons, HeT-A and TART. These are the first transposable elements with identified roles in chromosome structure. We suggest that these elements may be evolutionarily related to telomerase; in both cases an enzyme extends the end of a chromosome by adding DNA copied from an RNA template. The evolution of transposable elements from chromosomal replication mechanisms may have occurred multiple times, although in other organisms the new products have not replaced the endogenous telomerase, as they have in Drosophila. This is somewhat reminiscent of the oncogenes that have arisen from cellular genes. Perhaps the viruses that carry oncogenes have also arisen from cellular genetic systems.
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    The evolution of Ty1-copia group retrotransposons in eukaryote genomes (1997)
    Springer
    Genetica 100 (1997), S. 185-195 
    Details
    ISSN: 1573-6857
    Keywords: biodiversity ; copia ; evolution ; genome organization ; retrotransposon ; Ty element
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Ty1-copia group of LTR retrotransposons has been studied extensively in yeast and Drosophila, the organisms in which they were first discovered, and more recently in higher plant and vertebrate species. Their properties, such as copy number, sequence homogeneity, transcriptional and transpositional activity vary greatly between these different hosts. We will try to resolve these apparent discrepancies between these properties, explain any fundamental differences in the biology of the Ty1- copia group between hosts, and propose a general model for LTR retrotransposon evolution.
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    URL: http://dx.doi.org/10.1023/A:1018385713293
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    Bare-Id, a representative of a family of BARE-like elements of the barley genome (1997)
    Springer
    Genetica 100 (1997), S. 231-240 
    Details
    ISSN: 1573-6857
    Keywords: barley ; evolution ; Hordeum ; retrotransposon ; Ty1-copia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In our search for transposable elements in barley, Hordeum vulgare, we have isolated and cloned two BamHI-fragments of 4.7 and 4.2 kb in length containing very abundant DNA sequences. The 4.7 kb fragment is homologous to the extended region, including more than half of the 5′-LTR and some part of the coding domain of BARE-1, a member of copia-like retrotransposon family of barley. The 4.2 kb fragment, bearing homology to BARE-1 and the WIS-2 family isolated from wheat, is unique among studied retroelements of cereals because it consists of two inverted parts, each containing homology to the LTR and UTL of BARE-1. Functional motifs for reverse transcription, two TATA-boxes and two primer-binding sites, were found within the LTRs. The element contained within this fragment was generated by significant rearrangement of a BARE-like retrotransposon, which included inversion of the extended 5′-terminal region and deletion of the internal domain. Therefore this element is named BARE-ID (BARE-inverted, deleted). A family of BARE-like elements is amplified in the H. vulgare genome compared with wild barley species. The terminal inverted repeat of BARE-ID was used as a probe for examination of evolutionary diversity within genus Hordeum. Our data are basically in agreement with the modern classification system. However, they do not support the combination of H. vulgare and H. bulbosum into one group with the same type of genome. New data concerning the possible origin of the polyploid species, H. secalinum, confirm that retrotransposons are a useful tool for phylogenetic studies.
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    URL: http://dx.doi.org/10.1023/A:1018350100089
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    Biopolitics: the newest synthesis? (1997)
    Springer
    Genetica 99 (1997), S. 173-184 
    Details
    ISSN: 1573-6857
    Keywords: evolution ; genetics ; neurophysiology ; philosophy ; politics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract On first impression, the disciplines of genetics and political science would appear to be unrelated. And yet, commencing more than 30 years ago, the interdisciplinary field known as Biopolitics has now taken hold. This essay traces the central thrust of the biopolitical research agenda. It describes, analyzes, and assesses how political scientists have sought to show connections between our species' genetic constitution and our species' political behavior. Important bridges between the two are the neurophysiology of the human brain and the role of evolutionary theory in charting man's adaptational political profile. The parameters of the emerging biopolitical literature raise profound policy questions, some of which are also characterized.
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    URL: http://dx.doi.org/10.1007/BF02259521
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    Mapping chromosomal homology between humans and the black-handed spider monkey by fluorescence in situ hybridization (1997)
    Springer
    Chromosome research 5 (1997), S. 527-536 
    Details
    ISSN: 1573-6849
    Keywords: Ateles geoffroyi ; chromosome painting ; cytogenetics ; evolution ; phylogeny ; Platyrrhini ; taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We hybridized human chromosome-specific DNA probes to metaphases of the New World monkey Ateles geoffroyito map the chromosomal homology between these two species. In the haploid Ateles geoffroyi karyotype the total number of signals was 51 for the 22 human autosomal probes used. Compared with Old World monkeys, the number of translocations found in the black-handed spider monkey karyotype was quite striking. The majority of these translocations are apparently Robertsonian and no reciprocal translocations were revealed. Nine autosomal human chromosome probes (11, 13, 14, 17, 18, 19, 20, 21, 22) provided only two signals each per metaphase, but six of these were translocated to subregions of different spider monkey chromosomes. The other 13 autosomal human chromosome paints (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 16) provided fragmented signals. Three human probes (5, 8, 10) provided signals located on two pairs of spider monkey chromosomes. Four human paints (2, 3, 4, 12) provided hybridization signals on three pairs of chromosomes. Probes 6, 7, 15 provided six signals each on two pairs of chromosomes; probe 16 gave eight signals on two pairs of spider monkey chromosomes and probe 1 gave 12 signals on four pairs of chromosomes. The synteny between segments to human 18/8 appears to be an apomorphic ancestral condition for all New World monkeys. A synteny between regions homologous to human 16/10, 5/7 and 2/16 HSA is probably an apomorphic ancestral condition for all Cebidae. The syntenic association 3/15 and 4/1 is an apomorphic condition for the Atelinae.
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    Zoo-fluorescence in situ hybridization analysis of human and Indian muntjac karyotypes (Muntiacus muntjak vaginalis) reveals satellite DNA clusters at the margins of conserved syntenic segments (1997)
    Springer
    Chromosome research 5 (1997), S. 254-261 
    Details
    ISSN: 1573-6849
    Keywords: chromosome ; evolution ; comparative mapping ; Indian muntjac ; satellite DNA ; zoo-fluorescence in situ hybridization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Zoo-fluorescence in situ hybridization (FISH) with human whole chromosome-specific paint probes revealed extensive homoeologies between Indian muntjac (2n=6, 7 female, male) and human karyotypes (2n=46). Forty-two conserved syntenic segments, corresponding to all human chromosomes except the Y chromosome, produced a near-complete coverage of the muntjac complement and revealed margins of interspecific segmental homoeology. To test the hypothesis that interstitial satellite DNA loci, illuminated by a Chinese muntjac C5-satellite probe in Indian muntjac chromosome arms, mark ancestral fusion points (Lin CC, Sasi R, Fan YS, Chen Z-Q (1991) New evidence for tandem chromosome fusions in the karyotypic evolution of the Asian muntjacs. Chromosoma 101: 19–24), we combined Zoo-FISH with C5 satellite mapping. Twenty-six interstitial satellite DNA loci were detected in the haploid Indian muntjac genome and were found to co-localize with the margins of conserved human/Indian muntjac syntenic segments. These results were confirmed by two-colour FISH and are in accordance with the tandem fusion hypothesis for Indian muntjac chromosomes. Furthermore, conserved syntenic segment combinations detected in pig, cattle and Indian muntjac Zoo-FISH maps reveal ancestral artiodactyl chromosomes.
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    URL: http://dx.doi.org/10.1023/B:CHRO.0000032298.22346.46
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    The Ty1-copia group of retrotransposons in plants: genomic organisation, evolution, and use as molecular markers (1997)
    Springer
    Genetica 100 (1997), S. 205-217 
    Details
    ISSN: 1573-6857
    Keywords: Ty1-copia ; retrotransposons ; retroelements ; plants ; genomic organisation ; evolution ; molecular marker
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The genomic organisation and diversity of the Ty1-copia group retrotransposons has been investigated in several crop plants and their relatives from both dicotyledonous and monocotyledonous families, including potato ( Solanum tuberosum), faba beans ( Vicia faba), Vicia melanops, Vicia sativa, barley ( Hordeum vulgare), rye ( Secale cereale), and onion ( Allium cepa). Extreme heterogeneity in the sequence of the Ty1-copia retrotransposons from all these plants was revealed following sequence analysis of reverse transcriptase fragments. The estimated copy numbers of the Ty1-copia group retrotransposons for the genomes of S. tuberosum, L. esculentum, A. cepa, S. cereale, and V. faba is highly variable, ranging from a few hundred to approximately a million copies per genome. In situ hybridisation data from metaphase and prophase chromosomes of V. faba, S. cereale, and H. vulgare suggest that retrotransposon sequences are dispersed throughout the euchromatic regions of the genome but are almost undetectable in most heterochromatic regions. In contrast, similar data from metaphase chromosomes of A. cepa suggests that although retrotransposon sequences are dispersed throughout the euchromatic regions of the genome, they are predominantly concentrated in the terminal heterochromatin. These results are discussed in the context of the role played by the Ty1-copia group retrotransposons in the evolution of the plant genome. Lastly, the application of retrotransposon sequences as genetic markers for mapping genomes and for studying genetic biodiversity in plants is presented.
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    URL: http://dx.doi.org/10.1023/A:1018393931948
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    Old age, multiple formations or genetic plasticity? Clonal diversity in the uniparental Caucasian rock lizard, Lacerta dahli (1997)
    Springer
    Genetica 101 (1997), S. 125-130 
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    ISSN: 1573-6857
    Keywords: evolution ; Lacertadahli ; parthenogenesis ; uniparentality ; unisexuality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Allozyme variation at 35 gene loci is investigated in 161 specimens of the uniparental Caucasian lizard Lacerta dahli from several locations in Armenia and Georgia. All individuals are heterozygotic at 12 loci, and homozygotic at 21 loci. Variation at two loci results in five uniparental clones. One clone is widespread whereas four are geographically restricted and are represented by only one or two individuals. Because successful formation of uniparental clones is rare, and because the biparental species forming them are now allopatric, the most probable explanation for the origin of the observed clonal diversity is either mutation or recombination within the common clone. The rare clones have lower levels of enzyme activity at four loci, suggesting that these organisms may be genetically deficient. Although the evidence points to change in a pre-existing clone, the possibility of multiple origins cannot be ruled out.
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    On the origin of photosynthesis as inferred from sequence analysis (1997)
    Springer
    Photosynthesis research 51 (1997), S. 27-42 
    Details
    ISSN: 1573-5079
    Keywords: Photosystem I ; Photosystem II ; photosynthetic reaction center ; bacteriorhodopsin ; evolution ; UV-protection ; t Rhodopseudomonasviridis ; t Heliobacillus mobilis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sequence alignments between membrane-spanning segments of pheophytin-quinone-type photosynthetic reaction centers, FeS-type photosynthetic reaction centers, core chlorophyll-proteins of PS II, chlorophyll t a/t b-containing antenna proteins of plants and light-harvesting complexes of purple bacteria led us to postulate a large common ancestral pigment-carrying protein with more than 10 membrane spans. Its original function as a UV-protector of the primordial cell is discussed. It is conceivable that a purely dissipative photochemistry started still in the context of the UV-protection. We suggest that mutations causing the t loss of certain porphyrin-type pigments led to the acquisition of redox cofactors and paved the way for a gradual transition from dissipative to productive photochemistry.
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    Economics and Biological Evolution (1997)
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    Environmental and resource economics 9 (1997), S. 429-449 
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    ISSN: 1573-1502
    Keywords: evolution ; economics ; pesticide resistance ; antibiotic resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
    Notes: Abstract The employment of insecticides raises the relative fitness of resistant insects; the use of antibiotics applies selection pressure in favour of resistant strains of bacteria; lower limits on fish net mesh size raises the advantages of smaller adults. These are some of the many examples of the unintended impact of human activity upon biological evolution. Often this evolution has economic significance, as it does in the examples quoted. This paper examines some of the principles involved and provides a preliminary analysis of the extent to which the economically optimal inducement of evolution differs from that arising when changes in selection pressures are not anticipated.
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    URL: http://dx.doi.org/10.1023/A:1026411423178
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    Cuticular Hydrocarbons as Chemotaxonomic Characters of Pine Engraver Beetles (Ips spp.) in the grandicollis Subgeneric Group (1997)
    Springer
    Journal of chemical ecology 23 (1997), S. 1053-1099 
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    ISSN: 1573-1561
    Keywords: Scolytidae ; Ips ; Orthotomicus ; Pinus ; evolution ; cuticular hydrocarbons ; chemotaxonomy ; methyl-branched hydrocarbons ; mass spectrometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Cuticular hydrocarbons were extracted, identified, and evaluated as chemotaxonomic characters from all species of adult Ips pine engraver beetles in the grandicollis subgeneric group. The grandicollis group consists of Ips grandicollis (Eichhoff), I. cribricollis (Eichhoff), I. lecontei Swaine, I. montanus (Eichhoff), I. paraconfusus Lanier, I. confusus (LeConte), and I. hoppingi Lanier. In order to provide outgroups for a phylogenetic analysis, cuticular hydrocarbons were also analyzed from Orthotomicus caelatus (Eichhoff), I. latidens (LeConte) (latidens subgeneric group), and I. pini (Say) (pini subgeneric group). Two hundred forty-eight hydrocarbon components were identified by gas chromatography–mass spectrometry. The members of the grandicollis group provided 206 of these compounds. The components represented eight classes: n-alkanes, alkenes, alkadienes, terminally branched methylalkanes, internally branched methylalkanes, dimethylalkanes, trimethylalkanes, and tetramethylalkanes. Different populations of O. caelatus, I. grandicollis, I. lecontei, I. montanus, I. paraconfusus, I. confusus, and I. hoppingi provided no evidence for interpopulational variation in cuticular hydrocarbons. Single populations only were analyzed for I. latidens, I. pini, and I. cribricollis. Sexual dimorphism in cuticular hydrocarbons occurred only in I. lecontei where females produced eight unique components with a pentatriacontane parent chain. Several phylogenetic analyses based on hydrocarbon phenotypes agreed in general with the established morphologically based system of relatedness and with published phylogenies reconstructed from protein and nucleic acid characters. Nearly all hydrocarbon analyses suggested a close relationship between I. grandicollis and I. cribricollis; between I. lecontei and I. montanus; and among the sibling species I. paraconfusus, I. confusus, and I. hoppingi. The presence or absence of specific n-alkanes (n-docosane, n-triacontane); certain dimethylalkanes (terminally branched with octacosane and triacontane parent chains and internally branched with heptacosane, hentriacontane, and docotriacontane parent chains); and 3,7,11-; 3,7,15-trimethylheptacosane permit facile discrimination of I. paraconfusus, I. confusus, and I. hoppingi. These three sibling species are difficult to resolve by external morphology. These data support the species status of I. hoppingi rather than it being considered a host race of the I. confusus complex. They also support the species status of I. cribricollis rather than it being considered part of I. grandicollis. In contrast to other published phylogenies reconstructed from molecular data, phylogenies reconstructed from cuticular hydrocarbons repeatedly place I. lecontei as an integral part of the grandicollis subgeneric group. Thus, cuticular hydrocarbon and pheromone alcohol composition of I. lecontei support its inclusion in the grandicollis subgeneric group.
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    The effect of various host species on the feeding performance of immature stages of the tick Hyalomma truncatum (Acari: Ixodidae) (1997)
    Springer
    Experimental and applied acarology 21 (1997), S. 551-559 
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    ISSN: 1572-9702
    Keywords: Ticks ; Hyalomma truncatum ; feeding performance ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In order to determine the effect of various hosts on the feeding performance of the tick Hyalomma truncatum, we used three mammalian species as hosts. Larvae and nymphs of H. truncatum were fed, under controlled laboratory conditions, on gerbils, guinea-pigs and rabbits. The larvae fed for 4.3±1.4 days on gerbils, 5.6±1.3 days on guinea-pigs and 4.7±1.2 days on rabbits. The mean weights of the larvae which fed on the rabbits, guinea-pigs and gerbils were 0.58± 0.09, 0.46±0.04 and 0.45±0.04 mg. respectively. The feeding periods of the nymphs on gerbils, guinea-pigs and rabbits were 7.9±1.3, 8.6±1.3 and 9.6±2.2 days respectively. The mean weights of the nymphs which fed on the gerbils, guinea-pigs and rabbits were 22.5±2.8, 19.7±1.3 and 15.8±1.4 mg, respectively. Hyalomma truncatum demonstrated a life cycle of a three-host tick on gerbils and guinea-pigs and of a two-host tick on rabbits. The evolutionary advantage of a two-host cycle over a three-host cycle in metastriate ticks is discussed.
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    Bacterial evolution and silicon (1997)
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    Antonie van Leeuwenhoek 71 (1997), S. 271-276 
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    ISSN: 1572-9699
    Keywords: bacteria ; evolution ; molecular ; silicon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This review examines the possible role of silicon in molecular evolution. It is possible silicon participated in early molecular evolution by providing a stable mineral surface or gel structure where the assembly and replication of primitive genetic information occurred. However, as molecular evolution proceeded, silicon was not required in the evolution of C-based organisms. Silicon can be accumulated by diatoms and other living organisms such as silicoflagellates, some xanthophytes, radiolarians and actinopods and plants such as grasses, ferns, horseradish, some trees and flowers, some sponges, insects and invertebrates and bacteria and fungi. Silicon also has a role in synthesis of DNA, DNA polymerase and thymidylate kinase activity in diatoms. It is not unreasonable to examine the role of silicon in early molecular evolution as it may have been part of a micro-environment in which assembly of genetic information occurred.
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    URL: http://dx.doi.org/10.1023/A:1000183732698
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    Chloroplast DNA diversity in brinjal eggplant (Solanum melongena L.) and related species (1997)
    Springer
    Euphytica 97 (1997), S. 295-301 
    Details
    ISSN: 1573-5060
    Keywords: chloroplast DNA ; brinjal eggplant ; Solanum incanum ; Solanum melongena ; Solanum aethiopicum ; systematics ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Chloroplast DNA (cpDNA) samples of brinjal eggplant (S. melongena) and representative related species including S. incanum sensu lato (or S. campylacanthum sensu stricto), S. lichtensteinii, S. marginatum, S. macrocarpon, S. anguivi and S. aethiopicum and also S. nigrum as an outgroup taxon, were digested by 14 restriction enzymes and analyzed by using electrophoresis and a cpDNA probe. All the species used here were clearly separated in the cpDNA analysis, except the pair S. anguivi and S. aethiopicum. From the dendrogram constructed by the unweighted pair-group method, it is suggested that S. incanum is the closest to S. melongena and the next closest species is S. macrocarpon followed by S. aethiopicum (and S. anguivi), S. lichtensteinii, S. marginatum and finally the outgroup taxon S. nigrum. The tree derived by the neighbour-joining method suggests phyletic relationships that agree with those indicated by crossability and seed coat anatomy, but conflict with conventional classifications based on morphology. In particular, members of sections Oliganthes and Melongena are not separated and no cpDNA variation was found within either of the morphologically diverse cultigens, S. aethiopicum and S. melongena. Paradoxically, the morphologically similar species S. incanum, S. lichtensteinii and S. marginatum have diverged greatly in their cpDNA. The significance of these results is discussed.
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    URL: http://dx.doi.org/10.1023/A:1003000612441
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    The impact of molecular systematics on hypotheses for the evolution of root nodule symbioses and implications for expanding symbioses to new host plant genera (1997)
    Springer
    Plant and soil 194 (1997), S. 185-192 
    Details
    ISSN: 1573-5036
    Keywords: actinorhizal plants ; evolution ; nitrogen fixation ; phylogenetic hypotheses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Current taxonomic schemes place plants that can participate in root nodule symbioses among disparate groups of angiosperms. According to the classification scheme of Cronquist (1981) which is based primarily on the analysis of morphological characters, host plants of rhizobial symbionts are placed in subclasses Rosidae and Hamamelidae, and those of Frankia are distributed among subclasses Rosidae, Hamamelidae, Magnoliidae and Dilleniidae. This broad phylogenetic distribution of nodulated plants has engendered the notion that nitrogen fixing endosymbionts, particularly those of actinorhizal plants, can interact with a very broad range of unrelated host plant genotypes. New angiosperm phylogenies based on DNA sequence comparisons reveal a markedly different relationship among nodulated plants and indicate that they form a more coherent group than has previously been thought (Chase et al., 1993; Swensen et al., 1994; Soltis et al., 1995). Molecular data support a single origin of the predisposition for root nodule symbiosis (Soltis et al., 1995) and at the same time support the occurrence of multiple origins of symbiosis within this group (Doyle, 1994; Swensen, 1996; Swensen and Mullin, In Press).
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    Biological nitrogen fixation in non-leguminous field crops: Facilitating the evolution of an effective association between Azospirillum and wheat (1997)
    Springer
    Plant and soil 194 (1997), S. 65-79 
    Details
    ISSN: 1573-5036
    Keywords: Azospirillum brasilense ; evolution ; nifA-lacZ ; nifH-lacZ ; nitrogen fixation ; para-nodules ; symbiosis ; wheat ; 2 ; 4-D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Recent advances towards achieving significant nitrogen fixation by diazotrophs in symbioses with cereals are reviewed, referring to the literature on the evolution of effective symbioses involving rhizobia and Frankia as microsymbionts. Data indicating that strains of Acetobacter and Herbaspirillum colonizing specific cultivars of sugarcane as endophytes make a significant contribution to the nitrogen economy of this crop improves the prospects that similar associative systems may be developed for other gramineous species such as rice and wheat. By contrast, the transfer of nodulation genes similar to those in legumes or Parasponia to achieve nodulation in crops like rice and wheat is considered to be a more ambitious and distant goal. Progress in developing an effective associative system for cereals has been materially assisted by the development of genetic tools based on the application of lacZ and gusA fusions with the promoters of genes associated with nitrogen fixation. These reporter genes have provided clear evidence that ‘crack-entry’ at the points of emergence of lateral roots or of 2,4-D induced para-nodules is the most significant route of endophytic colonization. Furthermore, using the laboratory model of para-nodulated wheat, there is now evidence that the ability of azospirilla and other nitrogen fixing bacteria to colonize extensively as endophytes can be genetically controlled. The most successful strain of Azospirillum brasilense (Sp7-S) for endophytic colonization and nitrogen fixation in wheat seedlings is a mutant with reduced exopolysaccharide production. Most other strains of azospirilla do not colonize as endophytes and it is concluded that though these are poorly adapted to providing nitrogen for the host plant, they are well adapted for survival and persistence in soil. A research program combining the study of endophytic colonization by azospirilla with an examination of the factors controlling the effectiveness of association (oxygen tolerance and nitrogen transfer) is now being pursued. It is proposed that a process of facilitated evolution of para-nodulated wheat involving the stepwise genetic improvement of both the prospective microsymbionts and the cereal host will eventually lead to effective nitrogen-fixing associations. In the attempt to achieve this goal, continued study of the endophytes occurring naturally in sugar cane and other grasses (e.g. Azoarcus sp.) should be of assistance.
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    Mutation in a novel gene required for photomixotrophic growth leads to enhanced photoautotrophic growth of Synechocystis sp. PCC 6803 (1997)
    Springer
    Photosynthesis research 53 (1997), S. 243-252 
    Details
    ISSN: 1573-5079
    Keywords: cyanobacteria ; evolution ; glucose-sensitivity ; photoacclimation ; photosynthesis ; polymorphism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the glucose-tolerant strain of Synechocystis sp. PCC 6803, we found two types of cells with distinct growth properties. Under photoautotrophic conditions at any light intensity, one type gave larger colonies (designated WL) than the other (designated WS). Notably, the WL cells produced much larger colonies than the WS cells at higher light intensity. In contrast, growth of the WL cells was severely suppressed under mixotrophic conditions with glucose and light, while the WS cells grew normally. A gene which could complement the WL phenotype was obtained from a wild-type genomic library. The gene, designated pmgA, coded for a 23 kDa polypeptide of 204 amino acid residues with no apparent homology to known genes. In the WL genome, the base substitution of T for C at position 193 of pmgA caused replacement of Leu with Phe at position 65 of the product. The phenotype of pmgA disruption mutants was similar to that of the WL cells, indicating that the WS cells expressed a functional pmgA product. By direct sequencing of polymerase chain reaction-amplified pmgA from genomic DNA, it was revealed as an example of microevolution that WL had expelled WS from the photoautotrophic culture of wild-type in our laboratory for a year or so. Mixed culture in liquid also demonstrated that the WL cells increased gradually under photoautotrophic conditions, while they decreased rapidly under photomixotrophic conditions. These results suggest that pmgA product is essential for photomixotrophic growth, whereas it represses photoautotrophic growth. To our knowledge, the WL cells and pmgA-disrupted mutants are the first in cyanobacteria, which shows much improved photosynthetic growth than wild-type especially at high light intensity.
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    The role of marine biota in the evolution of terrestrial biota: Gases and genes (1997)
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    Biogeochemistry 39 (1997), S. 139-164 
    Details
    ISSN: 1573-515X
    Keywords: atmospheric composition ; elemental composition ; evolution ; marine biota ; soils ; terrestrial biota
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract There is greater biodiversity (in the senseof genetic distance among higher taxa) ofextant marine than of terrestrialO2-evolvers. In addition tocontributing the genes from one group ofalgae (Class Charophyceae, DivisionChlorophyta) to produce by evolution thedominant terrestrial plants (Embryophyta),the early marine O2-evolvers greatlymodified the atmosphere and hence the landsurface when the early terrestrialO2-evolvers grew. The earliestterrestrial phototrophs (from geochemicalevidence) occurred 1.2 Ga ago, over 0.7 Gabefore the Embryophyta evolved, but wellafter the earliest marine (cyanobacterial)O2 evolvers (3.45 Ga) and marineeukaryotic O2 evolvers (2.1 Ga). Evenby the time of evolution of the earliestterrestrial O2-evolvers the marineO2-evolvers had modified the atmosphereand land environment in at least thefollowing five ways. Once photosyntheticO2 paralleling organic C burial hadsatisfied marine (Fe2+, S2-reductants, atmospheric O2 built (1) upto a considerable fraction of the extantvalue (although some was consumed inoxidising terrestrial exposed Fe2+ and(2) provided stratospheric O3 and thusa UV-screen. (3) CO2 drawdown to∼20-30times the extant level is attributableto net production, and burial, of organic Cin the oceans (plus other geologicalprocesses). Furthermore, (4) theirproduction of volatile organic S compoundscould have helped to supply S to inland sitesbut also (5) delivered Cl and Br to thestratosphere thus lowering the O3 leveland the extent of UV screening.
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    Independent amplification of two classes of Tourists in some Oryza species (1997)
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    Genetica 101 (1997), S. 145-152 
    Details
    ISSN: 1573-6857
    Keywords: evolution ; Oryza ; Tourist ; transposable element
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Transposable elements similar to Tourist elements from maize were isolated from the rice genome. The elements were about 300 bp, exhibited short terminal inverted repeats (TIR), and appeared to show preferential insertion at TAA sites. Some rice Tourist elements seem to have recently transposed. Based on the sequences of cloned elements, two classes of rice Tourist elements have been identified. Members of these two classes apparently amplified independently at different times in the past.
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    The chromosomal distributions of Ty1-copia group retrotransposable elements in higher plants and their implications for genome evolution (1997)
    Springer
    Genetica 100 (1997), S. 197-204 
    Details
    ISSN: 1573-6857
    Keywords: in situ ; hybridization ; centromeres ; retrotransposons ; genome organization ; evolution ; sequence evolution ; Arabidopsis ; barley
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Retrotransposons make up a major fraction – sometimes more than 40% – of all plant genomes investigated so far. We have isolated the reverse transcriptase domains of the Ty1-copia group elements from several species, ranging in genome size from some 100 Mbp to 23 000 Mbp, and determined the distribution patterns of these retrotransposons on metaphase chromosomes and within interphase nuclei by DNA:DNA in situ hybridization. With some exceptions, the reverse transcriptase domains were distributed over the length of the chromosomes. Exclusion from rDNA sites and some centromeres (e.g., slash pine, 23 000 Mbp, or barley, 5500 Mbp) is frequent, whereas many species exclude retrotransposons from other sites of heterochromatin (e.g., intercalary and centromeric sites in broad bean). In contrast, in the plant Arabidopsis thaliana, widely used for plant molecular genetic studies because of its small genome (c. 100 Mbp), the Ty1-copia group reverse transcriptase gene domains are concentrated in the centromeric regions, collocalizing with the 180 bp satellite sequence pAL1. Unlike the pAL1 sequence, however, the Ty1-copia signal is also detectable as weaker, diffuse hybridization along the lengths of the chromosomes. Possible mechanisms for evolution of the contrasting distributions are discussed. Understanding the physical distribution of retrotransposons and comparisons of the distribution between species is critical to understanding their evolution and the significance for generation of the new patterns of variability and in speciation.
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    Cytogenetics of the Genus Leporinus (Pisces, Anostomidae). II. Molecular Cytogenetics, Organization and Evolutionary Conservation of a Chromosome-Specific Satellite DNA from Leporinus obtusidens (1997)
    Springer
    Chromosome research 5 (1997), S. 325-331 
    Details
    ISSN: 1573-6849
    Keywords: evolution ; fish molecular cytogenetics ; Leporinus ; satellite DNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A chromosome-specific satellite DNA from the South American fish species Leporinus obtusidens has been isolated and characterized. Sequence analysis and Southern hybridization studies indicate that the cloned 483-bp fragment is 60% AT rich and appears to comprise two diverged monomers. A highly variable low-copy number polymorphism was detected and, thus, this satellite DNA may serve as a valuable genetic marker. Using a Southern blot approach, the cloned satellite DNA cross-hybridized strongly to the DNA of Leporinus elongatus but failed to detect homologous sequences in the genomes of other closely related Leporinus species and higher vertebrates. Using fluorescence in situ hybridization to mitotic metaphase spreads of L. obtusidens and L. elongatus, this satellite DNA was located to the (peri)centromeric region of one single chromosome pair in both species. As the cloned satellite DNA sequence clearly evolved along a chromosomal lineage and is highly variable, it may serve as a very useful marker in further genetic, molecular and cytogenetic studies of the genus Leporinus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/B:CHRO.0000038763.52875.48
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    Do the integrases of LTR-retrotransposons and class II element transposases have a common ancestor? (1997)
    Springer
    Genetica 100 (1997), S. 63-72 
    Details
    ISSN: 1573-6857
    Keywords: DDE signature ; evolution ; integrase ; transposable elements ; transposase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The integrases of retrotransposons (class I) and retroviruses and the transposases of bacterial type elements (class II) were compared. The DDE signature that is crucial for the integration of these elements is present in most of them, except for the non-LTR retrotransposons and members of the hAT and P super-families. Alignment of this region was used to infer the relationships between class II elements, retrotransposons, and retroviruses. The mariner-Tc1 and the Pogo-Fot1 super-families were found to be closely related and probably monophyletic, as were LTR retrotransposons and retroviruses. The IS elements of bacteria were clustered in several families, some of them being closely related to the transposase of the mariner-Tc1 super-family or to the LTR retrotransposon and retrovirus integrases. These results plus that of Xiong and Eickbush (1990) were used to develop an evolutionary history suggesting a common ancestral origin(s) for the integrases and transposases containing the DDE signature. The position of the telomeric elements (Het-A and TART) was assessed by comparing their gag and reverse transcriptase domains (when present) to those of group II introns and non-LTR retrotransposons. This preliminary analysis suggests that telomeric elements may be derived from non-LTR retrotransposons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018300721953
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    Genomic distribution of the retrovirus-like element ZAM in Drosophila (1997)
    Springer
    Genetica 100 (1997), S. 131-140 
    Details
    ISSN: 1573-6857
    Keywords: Drosophila ; evolution ; FISH on Drosophila chromosomes ; genomic distribution ; retrotransposons retrovirus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The mobile element ZAM, recently identified in Drosophila melanogaster, is similar in structure and coding potential to vertebrate retroviruses. In this paper, we analyze the insertional and structural polymorphism of this element and show that members of this family appear to have a long evolutionary history in the genome of Drosophila. It is present in all the species of the D. melanogaster subgroup and in more distantly related species like D. takahashii, D. ananassae, or D. virilis but in a lower copy number or with a lower homology. Two categories of strains have been previously identified in D. melanogaster: strains with a high copy number of ZAM and strains with a low copy number. Here, we show that ZAM is at least in a low copy number in each tested strain of the species analyzed. The study of ZAM's genomic distribution by FISH mapping analysis to salivary gland polytene chromosomes or on mitotic chromosomes indicates that most of the insertion sites of ZAM elements are associated with the constitutive heterochromatin regardless of the ZAM copy number. In addition, our results suggest that multiple ZAM elements are present at the insertion sites visualized by in situ experiments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018317209658
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    Molecular and morphological characterization of monosomic additions in Beta vulgaris, carrying extra chromosomes of B. procumbens or B. patellaris (1997)
    Springer
    Molecular breeding 3 (1997), S. 147-157 
    Details
    ISSN: 1572-9788
    Keywords: Beta vulgaris ; Beta patellaris ; Beta procumbens ; section Procumbentes ; monosomic additions ; DNA fingerprinting ; repetitive probe ; morphological characteristics ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract DNA fingerprinting with three repetitive DNA sequences (OPX2, PB6-4 and Sat-121) was carried out on a set of 10 monosomic additions of Beta procumbens and 75 anonymous B. patellaris-derived monosomic additions in B. vulgaris, for characterization of the alien chromosomes at the DNA level. The probes are Procumbentes-specific and distributed over all chromosomes. Morphological characteristics were also used for the classification of B. patellaris monosomic addition families and for comparison with the morphology of the addition families of B. procumbens. DNA fingerprinting revealed unique patterns for almost all individual addition chromosomes of B. procumbens. However, it was concluded that chromosomes 1 and 6 of B. procumbens may be identical with the only difference that the chromosome referred to as 6 carries a susceptible allele for beet cyst nematode (BCN) resistance. In contrast, it was concluded that the two addition types with chromosome 2 are carrying different chromosomes of B. procumbens, so that one of them was renumbered to become the new chromosome 6. DNA fingerprinting of 75 anonymous B. patellaris-derived monosomic additions facilitated the identification and characterization of the alien chromosomes and the grouping of these additions into nine different groups. Several of these groups could be divided in two sub-groups on the basis of small differences in banding patterns. The results of the DNA fingerprinting led to the conclusion that B. patellaris most likely is an allotetraploid. It was also deduced that the BCN gene(s) in this species are homozygous and located on chromosome 1, while the pair of homoeologous chromosomes does not carry such BCN gene(s). Because of the allotetraploid nature of B. patellaris, preferential association occurs between the two homologous chromosomes containing the allele(s) for BCN resistance. Each group of B. patellaris addition families united by DNA fingerprinting had comparable morphological characteristics. Some of these morphological traits appeared to be chromosome-specific and were very useful for primary classification of the addition families. However, the present study showed that these morphological traits are not adequate for the identification of all alien chromosomes without the aid of additional markers. Because of similarities observed between molecular characteristics or the effects on plant morphology of several chromosomes of B. procumbens and B. patellaris it was concluded that B. procumbens could have been involved in the evolutionary history of B. patellaris.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009693619852
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    New raninid crabs (Crustacea, Decapoda, Brachyura) from the late Maastrichtian of the Netherlands (1997)
    Springer
    Netherlands journal of geosciences 76 (1997), S. 293-299 
    Details
    ISSN: 1573-9708
    Keywords: Raninidae ; new taxa ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Three new raninid crabs, Lyreidina pyriformis gen. n., sp. n., Raniliformis chevrona sp. n., and Raniliformis prebaltica sp. n., are described from the Maastrichtian type area (SE Netherlands). The new genus Lyreidina is the third member within the subfamily Lyreidinae Guinot 1993, and the first anterolateral-spines-lacking representative from the Cretaceous. The evolutionary development of the genus Raniliformis Jagt, Collins & Fraaye (1993) seems to include a continuous lineage occlusa-prebaltica-baltica. R. chevrona is considered as an offshoot.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003139315718
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    Economics and biological evolution (1997)
    Springer
    Environmental and resource economics 9 (1997), S. 429-449 
    Details
    ISSN: 1573-1502
    Keywords: evolution ; economics ; pesticide resistance ; antibiotic resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
    Notes: Abstract The employment of insecticides raises the relative fitness of resistant insects; the use of antibiotics applies selection pressure in favour of resistant strains of bacteria; lower limits on fish net mesh size raises the advantages of smaller adults. These are some of the many examples of the unintended impact of human activity upon biological evolution. Often this evolution has economic significance, as it does in the examples quoted. This paper examines some of the principles involved and provides a preliminary analysis of the extent to which the economically optimal inducement of evolution differs from that arising when changes in selection pressures are not anticipated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02441760
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    The theory of everything and molecular evolution (1997)
    Springer
    World journal of microbiology and biotechnology 14 (1997), S. 171-176 
    Details
    ISSN: 1573-0972
    Keywords: Bacteria ; DNA ; evolution ; molecular ; optimization ; RNA ; theory ; time
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The theory of everything is discussed in relationship to early bacterial molecular evolution. The emphasis is on time, space (or location at the molecular level), the universal construction kit (elements contained in periodic table) and change per units of time that were necessary for early bacterial molecular evolution to occur.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008817726536
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    Bacterial population genetics (1997)
    Springer
    World journal of microbiology and biotechnology 14 (1997), S. 1-5 
    Details
    ISSN: 1573-0972
    Keywords: Bacteria ; DNA ; evolution ; genetics ; genome ; molecular ; population
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Bacterial population genetics is the study of natural bacterial genetic diversity arising from evolutionary processes. The roles of molecular mistakes, restriction–modification, plasmids and gene transfer in bacteria are also important components of population genetics. These aspects are of considerable scientific importance from a fundamental perspective, because of the short generation times of bacteria, their microscopic cell size, the large population sizes bacteria can achieve and their different mechanisms of gene transfer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008897128837
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