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  • evolution  (41)
  • Springer  (41)
  • Annual Reviews
  • Blackwell Publishing Ltd
  • National Academy of Sciences
  • 2005-2009
  • 1990-1994  (41)
  • 1980-1984
  • 1940-1944
  • 1992  (41)
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  • Springer  (41)
  • Annual Reviews
  • Blackwell Publishing Ltd
  • National Academy of Sciences
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  • 2005-2009
  • 1990-1994  (41)
  • 1980-1984
  • 1940-1944
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  • 1
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    Springer
    Cellular and molecular life sciences 48 (1992), S. 729-731 
    ISSN: 1420-9071
    Keywords: Urea cycle ; leech ; botryoidal tissue ; hirudineans ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Ornithine carbamoyltransferase (OCT) and arginase, but not arginine synthetase (AS), were detected in the body wall and gut tissues of the leech. The activities of these enzymes were not altered by starvation. The high activity of arginase in body wall is probably due to the association of the latter with botryoidal tissue. Hirudineans, which evolved from oligochaete ancestors, appear to have lost the citrulline-arginine segment of the urea cycle due to their ammonotelic mode of nitrogen excretion.
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  • 2
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    Journal for general philosophy of science 23 (1992), S. 85-103 
    ISSN: 1572-8587
    Keywords: life ; teleology ; evolution ; reality ; representation ; experience
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Nature of Science, Research, Systems of Higher Education, Museum Science
    Notes: Summary A comprehensive definition of the phenomenon called “life” led to the addition of many dimensions to the natural sciences, and especially the conscious mental dimension. Historical attention is paid not only to those employing the natural philosophical paradigms, but also to evolutionary theories and to the Kantian teleological philosophy. The belief that science can solve the riddle of life is a category of purposal thinking. A revised version of critical teleology is essential for comprehension of life.
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  • 3
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    Antonie van Leeuwenhoek 61 (1992), S. 1-33 
    ISSN: 1572-9699
    Keywords: Paracoccus denitrificans ; denitrification ; methylotrophy ; cytochromec ; cytochrome oxidase ; phylogeny ; evolution ; lateral gene transfer ; nitrogen fixation ; Thiosphaera pantotropha
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Denitrification and methylotrophy inParacoccus denitrificans are discussed. The properties of the enzymes of denitrification: the nitrate-nitrite antiporter, nitrate reductase, nitrite reductase, nitric oxide reductase and nitrous oxide reductase are described. The genes for none of these proteins have yet been cloned and sequenced fromP. denitrificans. A number of sequences are available for enzymes fromEscherichia coli, Pseudomonas stutzeri andPseudomonas aeruginosa. It is concluded that pathway specificc-type cytochromes are involved in denitrification. At least 40 genes are involved in denitrification. In methanol oxidation at least 20 genes are involved. In this case too pathway specificc-type cytochromes are involved. The sequence homology between the quinoproteins methanol dehydrogenase, alcoholdehydrogenase and glucose dehydrogenase is discussed. This superfamily of proteins is believed to be derived from a common ancestor. ThemoxFJGI operon determines the structural components of methanol dehydrogenase and the associatedc-type cytochrome. Upstream of this operon 3 regulatory proteins were found. The mox Y protein shows the general features of a sensor protein and the moxX protein those of a regulatory protein. Thus a two component regulatory system is involved in both denitrification and methylotrophy. The phylogeny of prokaryotes based on 16S rRNA sequence is discussed. It is remarkable that the 16S rRNA ofThiosphaera pantotropha is identical to that ofP. denitrificans. Still these bacteria show a number of differences.T. pantotropha is able to denitrify under aerobic circumstances and it shows heterotrophic nitrification. Nitrification and heterotrophic nitrification are found in species belonging to the β-and γ-subdivisions of purple non-sulfur bacteria. Thus the occurrence of heterotrophic nitrification inT. pantotropha which belongs to the α-subdivision of purple non-sulfur bacteria is a remarkable property. FurthermoreT. pantotropha contains two nitrate reductases of which the periplasmic one is supposed to be involved in aerobic denitrification. The nitrite reductase is of the Cu-type and not of the cytochromecd 1 type as inP. denitrificans. Also the cytochromeb of theQbc complex ofT. pantotropha is highly similar to its counterpart inP. denitrificans. It is hypothesized that the differences between these two organisms which both contain large megaplasmids is due to a combination of loss of genetic information and plasmid-coded properties. The distribution of a number of complex metabolic systems in eubacteria and in a number of species belonging to the α-group of purple non sulphur bacteria is reviewed. Two possibilities to explain this haphazard distribution are considered: 1. Lateral gene transfer between distantly related micro organisms occurs frequently. 2. The eubacterial ancestors must have possessed already these properties. The distribution of these properties is due to sporadic loss during evolutionary divergence. With respect to the occurrence and frequency of lateral gene transfer two opposing views exist. According to molecular biologists lateral gene transfer occurs frequently and is very easy. Bacteria are supposed to form one large gene pool. On the other hand population geneticists have provided evidence that strong systems operate that establish reproductive isolation between diverged species and even between closely related cell lines. Data on amino acid sequences of nitrogenase proteins, cytochromesc, cytochrome oxidases, β-subunits of ATP synthase and tryptophan biosynthetic enzymes of various micro organisms were reviewed. In all these cases phylogenetic trees could be constructed based on the amino acid sequence data. In all cases this phylogenetic tree was similar to the one based on 16S rRNA homology. Only in one case evidence for the occurrence of lateral gene transfer was obtained. Therefore it is concluded that lateral gene transfer played a minor role in the distribution of complex metabolic systems among prokaryotes. It must be stressed that this does not exclude the possibility that lateral gene transfer occurred frequently in the initial stage of bacterial evolution. It is hypothesized that the appearance of nitrogen fixation, denitrification and cytochrome oxidase formation were early events in the evolution of micro organisms. Both systems are supposed to have evolved only once. Subsequently the capacity to fix nitrogen or to denitrifymust have been lost many times, just as photosynthetic capacity is supposed to have been lost many times. During evolution many systems have been lost leading to a haphazard distribution of metabolic characters among bacteria. As an example it is suggested that organisms with a respiratory chain similar to that ofEscherichia coli arose by loss of the capacity to form the Qbc complex andc-type cytochromes. The remaining systems could be controlled much better however than in the ancestral organisms.
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  • 4
    ISSN: 1420-9098
    Keywords: Isoptera ; Termitidae ; Nasutitermitinae ; caste differentiation ; phylogeny ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The developmental pattern of the neuter castes was studied in the mandibulate nasute generaCornitermes, Embiratermes andRhynchotermes. InCornitermes walkeri, all the workers and soldiers are male. There are two larval and a single worker instar. Workers can molt into presoldiers. InEmbiratermes chagresi andRhynchotermes perarmatus, both sexes are present among the neuters. A slight sexual dimorphism (males 〉 females) is discernible among both larval instars and among workers ofE. chagresi; female workers can molt into presoldiers. InR. perarmatus, the sexual dimorphism is conspicuous from the first larval instar on. Male larvae go through two instars, then give rise to workers, which do not molt. InR. perarmatus, there is no worker stage in females, but a third larval instar, preceding the presoldier. Hypotheses are proposed as to the evolution of these caste patterns, attempting to conciliate present knowledge of Nasutitermitinae phylogeny and known evolutionary trends affecting termite caste patterns, according to the species' ecology.
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  • 5
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    Insectes sociaux 39 (1992), S. 425-438 
    ISSN: 1420-9098
    Keywords: Formicidae ; Nothomyrmecia ; evolution ; sociogram ; ethogram ; recognition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Results of laboratory-based ethological studies on twoNothomyrmecia macrops colonies with individually marked workers are reported. Interactive behavioural acts constituted less than 1% of all those recorded, revealing a strong tendency by the ants not to engage in social contact. Very few workers performed queen-directed acts. They stayed near the queen, though seldom in direct contact. Division of labour was otherwise barely apparent, except that some individuals showed a propensity to guard the nest entrance. No exchange of food was observed between workers, workers and queen, or adults and larvae (apart from worker placement of prey items with larvae). A queen fed from aDrosophila carcass retrieved from the nest floor, without assistance from workers. Systematic scanned observations confirmed levels of inactivity higher than previously observed in ants (comprising almost 2/3 of recorded behavioural acts). The time budget for activities directed toward the immature stages was the same in both colonies, and fluctuated during the circadian period. Non-nestmate larvae added to worker groups were more frequently licked than nestmate larvae, but this might not involve the particular recognition of nestmateversus non-nestmate brood. These observations support the hypothesis thatNothomyrmecia is primitively eusocial, and of special significance in myrmecology.
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  • 6
    ISSN: 1420-9071
    Keywords: Biological clock ; cell division cycle ; diaminopimelate ; evolution ; FSu ; lysine ; muramate ; muramyl dipeptide ; peptidoglycan ; sleep muropeptide ; tumor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Degradation products of peptidoglycan, the universal bacterial cell wall constituent, were previously found in animal tissues and urine. Reassessment and quantitative analysis of available data lead to an original concept, i.e. that eukaryotic cells synthesize peptidoglycan. We present a model in which this endogenously synthesized peptidoglycan is essential for the processes of eukaryotic cell division and sleep induction in animals. Genes for peptidoglycan metabolism, like those for lysine biosynthesis in plants, are probably inherited from endosymbiotic bacteria, the ancestors of mitochondria and chloroplasts. Corollaries of this concept, i.e. roles for peptidoglycan metabolism in tumor formation and in the biological clock, are supported by abundant evidence. We propose that many interactions between bacteria and eukaryotes are conditioned by their common genetic heritage.
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  • 7
    ISSN: 1420-9071
    Keywords: Molluscan insulin-related peptides ; schistosomin ; neuropeptide gene family ; generation of neuropeptide diversity ; stimulus-dependent expression ; information-handling capacity ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We review recent experiments showing that the cerebral neuroendocrine Light Green Cells (LGCs) of the freshwater snail,Lymnaea stagnalis, express a family of distinct though related molluscan insulin-related peptide (MIP) genes. The LGCs are involved in the regulation of a wide range of interrelated life processes associated with growth, (energy) metabolism and reproduction. We consider the mechanism of generation of diversity among MIPs, and present evidence that conditions with distinct effects on growth, metabolism and reproduction also can induce distinct patterns of expression of the MIP and schistosomin genes. The stimulus-dependent expression of multiple neuropeptide genes enormously increases the adaptive potential of a peptidergic neuron. We suggest that this contributes significantly to the information-handling capacity of the brain.
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  • 8
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    Molecular engineering 1 (1992), S. 377-399 
    ISSN: 1572-8951
    Keywords: Origin of life ; molecular engineering ; biology ; evolution ; genetic code ; translation machine ; self instruction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In attempting to understand how life originated, we search for a detailed sequence of experimentally testable physico-chemical steps in an appropriately structured system. This goal is approached in two stages. First we search for the organizational structure of processes leading to systems with the basic features of living organisms. This is an engineering problem: finding a certain construct by taking care of logical requirements and restrictions from physics. Then we face this construct with the chemical and geophysical reality, and this leads to the view that systems with the essential features of early living organisms evolve following a distinct pathway. Energy supply and the presence of a particular structure in space and time are necessary to induce and drive the processes triggered by stochastic events; but if these particular conditions are given, the broad line of the evolutionary processes is determined by logical requirements and by chemical and geophysical constrains and invariants. The genetic machinery considered to evolve in this manner agrees, in its organizational structure and in many details, with the actual genetic machinery of biosystems. A surprising simplicity and transparency is observed in the logic of the basic processes involved in the origin of life. In the present view, the processes leading to the origin of life begin in a very particular, highly structured, small region where the relevant chemistry can be quite different from overall prebiotic chemistry. Energy-rich compounds are present in ample amounts and a succession of physico-chemical processes, which are per se thermodynamically allowed, takes place. This is in contrast to popular views that the origin of life is connected with fundamental thermodynamic questions related to the problem of getting order out of chaos.
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  • 9
    ISSN: 1573-5028
    Keywords: Angiopteris lygodiifolia ; atpB ; chloroplast genome ; evolution ; rbcL ; trnR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To elucidate the evolutionary relationship between the Spermatophyta, Pteridophyta and Bryophyta, we cloned a fragment of chloroplast DNA from the fernAngiopteris lygodiifolia (Pteridophyta) and determined its nucleotide sequence. The fragment contained theatpB,rbcL,trnR-CCG,dedB andpsaI genes. Comparisons of the deduced amino acid and nucleotide sequences of these genes from the three plant groups indicate thatAngiopteris sequences are more closely related to those of Bryophyta species (85% identity on average) than to those of seed plants (76% identity on average), supporting a hypothesis that the Bryophyta and Pteridophyta diverged more recently from one another than their common progenitor diverged from that of the Spermatophyta.
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  • 10
    ISSN: 1573-5028
    Keywords: translation elongation factor genes ; promoter analysis ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In Arabidopsis thaliana, the activation process of the A1 EF-1α gene depends on several elements. Using the GUS reporter gene, transient expression experiments have shown that mutations of upstream cis-acting elements of the A1 promoter, or the deletion of an intron located within the 5′ non-coding region, similarly affect expression in dicot or monocot protoplasts. The results reported here strongly suggest that this 5′ intron is properly spliced in Zea mays. We show that two trans-acting factors, specifically interacting with an upstream activating sequence (the TEF 1 box), are present in nuclear extracts prepared from A. thaliana, Brassica rapa, Nicotiana tabacum and Z. mays. In addition, a DNA sequence homologous to the TEF 1 box, found at approximately the same location within a Lycopersicon esculentum EF-1α promoter, interacts with the same trans-acting factors. Homologies found between the A. thaliana and L. esculentum TEF 1 box sequences have allowed us to define mutations of this upstream element which affect the interaction with the corresponding trans-acting factors. These results support the notion that the activation processes of A. thaliana EF-1α genes have been conserved among angiosperms and provide interesting data on the functional structure of the TEF 1 box.
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  • 11
    ISSN: 1573-5028
    Keywords: Cyanidium caldarium Geitler ; evolution ; Galdieria sulphuraria ; inverted repeat ; plastid DNA ; psbD-psbC operon ; red algae ; 5S rRNA ; rpl21 ; rps16
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The four inverted repeat (IR) flanking regions of the Cyanidium caldarium plastid DNA were cloned. Southern blotting, transcript and sequence analyses of the border regions revealed the psbD-psbC operon and the rps16 gene within the large single-copy region upstream of the 16S rDNA gene and the rpl21 gene downstream of the 5S rDNA within the 16 kb small single-copy region. The size of the IR is ca. 5 kb. The nucleotide sequences of the psbD-psbC, rps16, rpl21 and 5S rRNA genes with the corresponding alignments and physical maps of the regions are presented. Northern analysis revealed a less complex psbD-psbC transcription pattern than has been found in higher plants. Comparisons to other red algal data point to structural diversity within red algal plastid DNA.
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  • 12
    ISSN: 1573-5028
    Keywords: higher plants ; sunflower ; chloroplast genome ; mitochondrial genome ; tRNAHis genes ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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  • 13
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    Plant molecular biology 18 (1992), S. 777-780 
    ISSN: 1573-5028
    Keywords: Cyanidium caldarium ; evolution ; Galdieria sulphuraria ; rRNA operon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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  • 14
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    Plant systematics and evolution 180 (1992), S. 53-64 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Euphorbiaceae ; Macaranga ; Ant-plant interactions ; domatia ; evolution ; myrmecophytism ; Flora of Malaysia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The paleotropical tree genusMacaranga (Euphorbiaceae) comprises all stages of interaction with ants, from facultative associations to obligate myrmecophytes. In SE.-Asia food availability does not seem to be the limiting factor for the development of a close relationship since all species provide food for ants in form of extrafloral nectar and/or food bodies. Only myrmecophyticMacaranga species offer nesting space for ants (domatia) inside internodes which become hollow due to degeneration of the pith. Non-myrmecophytic species have a solid stem with a compact and wet pith and many resin ducts. The stem interior of some transitional species remains solid, but the soft pith can be excavated. The role of different ant-attracting attributes for the development of obligate ant-plant interactions is discussed. In the genusMacaranga, the provision of nesting space seems to be the most important factor for the evolution of obligate myrmecophytism.
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  • 15
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    Plant systematics and evolution 180 (1992), S. 137-156 
    ISSN: 1615-6110
    Keywords: Angiosperms ; evolution ; origin ; ancestral angiosperm ; morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The ancestral angiosperm is commonly interpreted as an arborescent to shrubby magnolialean with large, multiparted, complex flowers. We examined this hypothesis using a phylogenetic analysis of new and reevaluated characters polarizabled with outgroup comparison. Our cladistic analysis of basal angiosperms placed the nonmagnolialeanChloranthaceae andPiperaceae at the bottom of the tree. We further inferred the probable ancestral states of characters not polarizable with outgroup comparison by examining their distribution among taxa at the base of our cladogram. The sum of ancestral character states suggests that the protoangiosperm was a diminutive, rhizomatous to scrambling perennial herb, with small, simple flowers.
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  • 16
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    Plant systematics and evolution 181 (1992), S. 33-43 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Fabaceae ; Medicago murex ; M. lesinsii ; Systematics ; evolution ; isozymes ; chromosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Chromosomal studies ofMedicago lesinsii (n = 8) and its close relativeM. murex (n = 7) have led to the competing hypotheses that the latter is derived directly from the former, or that both originated from a common ancestor. In contrast to the relatively variableM. murex, M. lesinsii proved to be almost uniform isozymically, except that most populations of Greece differed by one allele from plants of the remainder of the range. This Greek variant ofM. lesinsii was indistinguishable from one of the isozyme variants ofM. murex. The greater level of allozyme variation inM. murex was consistent with its greater ecological amplitude and competitive ability. Also, this suggests thatM. murex is unlikely to have originated directly from the less variableM. lesinsii. The data suggest that either both species originated from a common ancestor, or that the n = 8 species evolved from the n = 7 species, a mode of chromosome evolution not previously hypothesized for the genus.
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  • 17
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    Plant systematics and evolution 181 (1992), S. 179-202 
    ISSN: 1615-6110
    Keywords: Hyacinthaceae ; Ornithogalum ; Heliocharmos ; O. algeriense ; O. kochii ; O. orthophyllum ; O. umbellatum ; Numerical taxonomy ; phenetics ; systematics ; biogeography ; evolution ; Flora of North Africa ; Mediterranean ; Morocco ; Spain ; France
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A macromorphological study is made on taxa of the genusOrnithogalum subg.Heliocharmos in North Africa, Spain, and France. The results obtained are consistent with data from cytogenetics, reproductive biology and strategies of reproduction. They allow the retention of two species:O. algeriense andO. umbellatum. A biogeographical and phylogenetic interpretation of the subgenus is proposed for the western Mediterranean. Theoretical views on phenetics are discussed.
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  • 18
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    Plant systematics and evolution 183 (1992), S. 235-247 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Mimosaceae ; Acacia ; 5S DNA ; evolution ; phylogeny ; chromosomal lineages
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The DNA sequence structure of 5S DNA units inAcacia species, including representatives from the three subgenera ofAcacia, have been determined. The data was interpreted to suggest that at least three lineages of 5S DNA sequences exist inAcacia and the proposal was made that the lineages be named5S Dna-1, 5S Dna-2, and5S Dna-3. The5S Dna-1 lineage was represented by units fromA. boliviana andA. bidwilli, the5S Dna-2 lineage by units fromA. melanoxylon, A. pycnantha, A. ulicifolia, A. boliviana, A. bidwillii, andA. albida, and the5S Dna-3 lineage by units fromA. bidwillii, A. boliviana, andA. senegal. Based on this interpretation of the sequence data, the Australian species of subg.Phyllodineae grouped together as a cluster, quite separate from the subgeneraAculeiferum andAcacia. As expected from the analyses of morphological characters, the 5S DNA units fromAcacia albida (syn.Faidherbia albida) were quite separate from the otherAcacia spp.
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  • 19
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    Plant systematics and evolution 183 (1992), S. 249-264 
    ISSN: 1615-6110
    Keywords: Poaceae ; Oryza ; 5S DNA ; phylogeny ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Relationships between 9Oryza species, covering 6 different genomes, have been studied using hybridization and nucleotide sequence information from the5S Dna locus. Four to five units of the major size class of 5S DNA in each species, 55 units in all, were cloned and sequenced. Both hybridization and sequence data confirmed the basic differences between the A and B, C, D genome species suggested by morphological and cytological data. The 5S DNA units of the A genome species were very similar, as were the ones from the B, C, and D genome-containing species. The 5S DNA ofO. australiensis (E genome) grouped with the B, C, D cluster, while the units ofO. brachyantha (F genome) were quite different and grouped away from all other species. 5S DNA units fromO. minuta, O. latifolia, O. australiensis, andO. brachyantha hybridized strongly, and preferentially, to the genomic DNA from which the units were isolated and hence could be useful as species/genome specific probes. The 5S DNA units fromO. sativa, O. nivara, andO. rufipogon provided A genome-specific probes as they hybridized preferentially to A genome DNA. The units fromO. punctata andO. officinalis displayed weaker preferential hybridization toO. punctata DNA, possibly reflecting their shared genome (C genome).
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  • 20
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    Biology and philosophy 7 (1992), S. 1-12 
    ISSN: 1572-8404
    Keywords: Cognitive ethology ; mental content ; mental representations ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract Cognitive ethology is the comparative study of animal cognition from an evolutionary perspective. As a sub-discipline of biology it shares interest in questions concerning the immediate causes and development of behavior. As a part of ethology it is also concerned with questions about the function and evolution of behavior. I examine some recent work in cognitive ethology, and I argue that the notions of mental content and representation are important to enable researchers to answer questions and state generalizations about the function and volution of behavior.
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  • 21
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    Biology and philosophy 7 (1992), S. 27-33 
    ISSN: 1572-8404
    Keywords: Additivity ; ANOVA ; evolution ; hierarchical selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract It has been proposed that natural selection occurs on a hierarchy of levels, of which the organismic level is neither the top nor the bottom. This hypothesis leads to the following practical problem: in general, how does one tell if a given phenomenon is a result of selection on level X or level Y. How does one tell what the units of selection actually are? It is convenient to assume that a unit of selection may be defined as a type of entity for which there exists, among all entities on the same “level” as that entity, an additive component of variance for some specific component F of fitness which does not appear as an additive component of variance in any decomposition of this F among entities at any lower level. But such a definition implicitly assumes that if f(x, y) depends nonadditively on its arguments, there must be interaction between the quantities which x and y represent. This assumption is incorrect. And one cannot avoid this error by speaking of “transformability to additivity” instead of merely “additivity”. A general mathematical formulation of the concepts of interaction and non-interaction is proposed, followed by a correspondingly modified approach to the definition of a unit of selection. The practical difficulty of verifying the presence of hierarchical selection is discussed.
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  • 22
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    Biology and philosophy 7 (1992), S. 35-60 
    ISSN: 1572-8404
    Keywords: Action principles ; ecosystem structure ; evolution ; information ; natural selection ; non-equilibrium thermodynamics ; teleology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract The general attributes of ecosystems are examined and a naturally occurring “reference ecosystem” is established, comparable with the “isolated” system of classical thermodynamics. Such an autonomous system with a stable, periodic input of energy is shown to assume certain structural characteristics that have an identifiable thermodynamic basis. Individual species tend to assume a state of “least dissipation”; this is most clearly evident in the dominant species (the species with the best integration of energy acquisition and conservation). It is concluded that ecosystem structure results from the antagonistic interaction of two nearly equal forces. These forces have their origin in the Principle of Most Action (“least dissipation” or “least entropy production”) and the universal Principle of Least Action. “Most action” is contingent on the equipartitioning of the energy available, through uniform interaction of similar individuals. The trend to “Least action” is contingent on increased dissipation attained through increasing diversity and increasing complexity. These principles exhibit a basic asymmetry. Given the operation of these opposing principles over evolutionary time, it is argued that ecosystems originated in the vicinity of thermodynamic equilibrium through the resonant amplification of reversible fluctuations. On account of the basic asymmetry the system was able to evolve away from thermodynamic equilibrium provided that it remained within the vicinity of “ergodynamic equilibrium” (equilibrium maintained by internal work, where the opposing forces are equal and opposite). At the highest level of generalization there appear to be three principles operating: i) maximum association of free-energy and materials; ii) energy conservation (deceleration of the energy flow) through symmetric interaction and increased homogeneity; and iii) the principle of least action which induces acceleration of the energy flow through asymmetrical interaction. The opposition and asymmetry of the two forces give rise to natural selection and evolution.
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  • 23
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    Biology and philosophy 7 (1992), S. 61-68 
    ISSN: 1572-8404
    Keywords: Altruism ; evolution ; group selection ; selfishness
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract I examine the relationship between evolutionary definitions of altruism that are based on fitness effects and psychological definitions that are based on the motives of the actor. I show that evolutionary altruism can be motivated by proximate mechanisms that are psychologically either altruistic or selfish. I also show that evolutionary definitions do rely upon motives as a metaphor in which the outcome of natural selection is compared to the decisions of a psychologically selfish (or altruistic) individual. Ignoring the precise nature of both psychological and evolutionary definitions has obscured many important issues, including the biological roots of psychological altruism.
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  • 24
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    Biology and philosophy 7 (1992), S. 161-175 
    ISSN: 1572-8404
    Keywords: Altruism ; evolution ; Prisoner's Dilemma ; sociobiology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract I first argue against Peter Singer's exciting thesis that the Prisoner's Dilemma explains why there could be an evolutionary advantage in making reciprocal exchanges that are ultimately motivated by genuine altruism over making such exchanges on the basis of enlightened long-term self-interest. I then show that an alternative to Singer's thesis — one that is also meant to corroborate the view that natural selection favors genuine altruism, recently defended by Gregory Kavka, fails as well. Finally, I show that even granting Singer's and Kavka's claim about the selective advantage of altruism proper, it is doubtful whether that type of claim can be used in a particular sort of sociobiological argument against psychological egoism.
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    Biology and philosophy 7 (1992), S. 177-187 
    ISSN: 1572-8404
    Keywords: Altruism ; evolution ; game theory ; group selection ; kin selection ; prisoner's dilemma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract A simple and general criterion is derived for the evolution of altruism when individuals interact in pairs. It is argued that the treatment of this problem in kin selection theory and in game theory are special cases of this general criterion.
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  • 26
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    Biology and philosophy 7 (1992), S. 295-313 
    ISSN: 1572-8404
    Keywords: Clade ; class ; composite whole ; definition ; defining property ; essentialism ; evolution ; individual ; intension ; name ; ostensive definition ; phylogeny ; population ; set ; species ; taxon ; taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract An examination of the post-Darwinian history of biological taxonomy reveals an implicit assumption that the definitions of taxon names consist of lists of organismal traits. That assumption represents a failure to grant the concept of evolution a central role in taxonomy, and it causes conflicts between traditional methods of defining taxon names and evolutionary concepts of taxa. Phylogenetic definitions of taxon names (de Queiroz and Gauthier 1990) grant the concept of common ancestry a central role in the definitions of taxon names and thus constitute an important step in the development of phylogenetic taxonomy. By treating phylogenetic relationships rather than organismal traits as necessary and sufficient properties, phylogenetic definitions remove conflicts between the definitions of taxon names and evolutionary concepts of taxa. The general method of definition represented by phylogenetic definitions of clade names can be applied to the names of other kinds of composite wholes, including populations and biological species. That the names of individuals (composite wholes) can be defined in terms of necessary and sufficient properties provides the foundation for a synthesis of seemingly incompatible positions held by contemporary individualists and essentialists concerning the nature of taxa and the definitions of taxon names.
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    Evolutionary ecology 6 (1992), S. 187-197 
    ISSN: 1573-8477
    Keywords: parental care ; resource allocation ; ESS ; inclusive fitness ; menopause ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary To understand the evolution of parental care behaviour, the cost of care must be evaluated in terms of lost reproductive potential. Using population genetics theory, a quantitative model of parental care is presented here to evaluate the allocation of resources between production and care of offspring, and care of grandoffspring. The results show that the evolutionarily stable investment ratio of resources to offspring versus grandoffspring is equal to 2∶1. The expected investment in grandoffspring will decrease when there is a lower probability of survival of the parents to a late stage of the life cycle. These results are discussed in the context of general life history theory, inclusive fitness models, animal behaviour field studies, and the evolution of human menopause.
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    Plant systematics and evolution 179 (1992), S. 141-153 
    ISSN: 1615-6110
    Keywords: Gymnosperms ; Conifers ; Pinaceae ; Pinus ; rDNA ; restriction fragments ; molecular systematics ; evolution ; phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phylogenetic relationships among 30 species of the genusPinus were studied using restriction site polymorphism in the large subunit of nuclear rDNA. Of the 58 restriction sites scored, 48 were phylogenetically informative, and the 30 species reduced to ten taxa when species with identical restriction site patterns were combined. These ten taxa corresponded to the currently recognized subsections of the genus, with the sole exception ofP. leiophylla, which was identical in its pattern of restriction sites to all three species included from subsect.Oocarpae despite its being in a different section of subg.Pinus (Pinea instead ofPinus). A measure of the proportion of phylogenetic information contained within the data set (Homoplasy Excess Ratio, or HER) revealed that the character states were significantly non-randomly distributed among the ten taxa (HER = 0.71, p 〈 0.01). Branchand-bound searches using either Wagner or Dollo parsimony as the optimization criterion were carried out using PAUP in order to estimate phylogenetic relationships among the ten taxa. Three taxa (Picea pungens, Tsuga canadensis, andLarix decidua) were used independently as outgroups for purposes of rooting the trees. Despite the extreme differences in the assumptions underlying the Wagner and Dollo parsimony, the two gave surprisingly similar estimates of phylogeny, with both analyses supporting the monophyly of the two major subgeneraPinus andStrobus and differing in topology only in the placement of subsect.Ponderosae within subg.Pinus. The likelihood for the Wagner tree was only slightly higher than that computed for the Dollo tree.
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  • 29
    ISSN: 1573-5060
    Keywords: bridging crosses ; chromosome addition lines ; Endosperm Balance Number ; evolution ; 2n gametes ; imprinting ; interspecific crosses ; ploidy manipulations ; tuber-bearing Solanum species
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Endosperm failure is considered the primary reason for the lack of success in intra-and interspecific crosses. The Endosperm Balance Number (EBN) hypothesis is a unifying concept for predicting endosperm function in intraspecific, interploidy, and interspecific crosses. In the EBN system, every species has an ‘effective ploidy’ (EBN), which must be in a 2:1 maternal to paternal ratio in the endosperm for crosses to succeed. The knowledge of EBN is very useful in the transfer of genes from exotic germplasm, and in the development of new breeding schemes in potato. The paper describes the strategies for introducing 2x(1EBN), 2x(2EBN), 4x(2EBN) and 6x(4EBN) germplasm into the cultivated 4x(4EBN) potato gene pool. A new methodology for producing 4x(4EBN) and 2x(2EBN) chromosome addition lines is also discussed. EBN has evolutionary importance in the origin of tuber-bearing Solanums. The role of the EBN in the origin of diploid and polyploid potato species, and as a barrier for hybridization and speciation of sympatric species within the same ploidy level is demonstrated. The origin of 3x and 5x cultivated tuber-bearing Solanums may also be explained using the EBN concept. EBN has been reported to exist in other plant species: alfalfa, beans, blueberries, rice, soybeans, squashes, tomato, forage legumes, grasses, ornamentals and Datura stramonium. This indicates that EBN may have broad application and could be useful for germplasm transfer and breeding in other crop species.
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    Photosynthesis research 33 (1992), S. 163-170 
    ISSN: 1573-5079
    Keywords: biosynthetic pathway ; evolution ; free energy ; photochemistry ; photosynthesis ; porphyrin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Living matter is an organized system which requires a continual flux of energy for its survival. As a working assumption, the flux of energy required for the origin of a self-duplicating cell is taken as the power required for the maintenance of a modern cell: 10 mW per g of carbon or some 105 times the output per gram of the sun. Solar photochemistry supplies the energy for the continuing evolution of life and, by continuity, for its origin. The iron oxide-sulfide photosynthetic unit proposed by S. Granick 35 years ago was meant to supply this energy. The evolution of complex organic photosensitizers is rationalized by the Granick hypothesis that biosynthetic pathways recapitulate their evolution. These concepts are discussed in the context of the evolution of photosynthetic systems and the known properties of these pigments.
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  • 31
    ISSN: 1573-5079
    Keywords: iron-sulfur centers ; evolution ; green sulfur bacteria ; bacteriochlorophyll g
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Photosynthetic reaction centers isolated from Heliobacillus mobilis exhibit a single major protein on SDS-PAGE of 47 000 Mr. Attempts to sequence the reaction center polypeptide indicated that the N-terminus is blocked. After enzymatic and chemical cleavage, four peptide fragments were sequenced from the Heliobacillus mobilis apoprotein. Only one of these sequences showed significant specific similarity to any of the protein and deduced protein sequences in the GenBank data base. This fragment is identical with 56% of the residues, including both cysteines, found in the highly conserved region that is proposed to bind iron-sulfur center FX in the Photosystem I reaction center peptide that is the psaB gene product. The similarity to the psaA gene product in this region is 48%. Redox titrations of laser-flash-induced photobleaching with millisecond decay kinetics on isolated reaction centers from Heliobacterium gestii indicate a midpoint potential of −414 mV with n=2 titration behavior. In membranes, the behavior is intermediate between n=1 and n=2, and the apparent midpoint potential is −444 mV. This is compared to the behavior in Photosystem I, where the intermediate electron acceptor A1, thought to be a phylloquinone molecule, has been proposed to undergo a double reduction at low redox potentials in the presence of viologen redox mediators. These results strongly suggest that the acceptor side electron transfer system in reaction centers from heliobacteria is indeed analogous to that found in Photosystem I. The sequence similarities indicate that the divergence of the heliobacteria from the Photosystem I line occurred before the gene duplication and subsequent divergence that lead to the heterodimeric protein core of the Photosystem I reaction center.
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  • 32
    ISSN: 1573-6857
    Keywords: Compositae ; DNA amount ; evolution ; Guizotia ; karyotype
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The present communication deals with 2C nuclear genome size variation in a fairly small genus Guizotia. Twenty-four accessions belonging to six species, out of seven known, were analysed in order to elucidate the extent of DNA variation both at an intra—as well as interspecific level. At the intraspecific level none of the species exhibited significant differences in their genome size. Between the species, the 2C DNA amounts ranged from 3.61 pg in G. reptans to 11.37 pg in G. zavattarii; over three-fold DNA variation is evident. Apparently these interspecific DNA differences have been achieved independent of the numerical chromosomal change(s), as all the Guizotias share a common chromosome number 2n=2x=30. The cultivated oilseed crop, G. abyssinica (7.57 pg), has accommodated nearly 78% extra DNA in its chromosome complement during the evolutionary time scale of its origin and domestication from the wild progenitor G. schimperi (4.25 pg). The extent of genomic DNA difference(s) between the species has been discussed in the light of their interrelationships and diversity.
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    Genetica 86 (1992), S. 203-214 
    ISSN: 1573-6857
    Keywords: Copia ; Ty element ; evolution ; retrotransposon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Ty1-copia group retrotransposons are among the best studied transposable elements in the eukaryotes. This review discusses the extent of these transposons in the eukaryote kingdoms and compares models for the evolution of these genetic elements in the light of recent phylogenetic data. These data show that the Ty1-copia group is widespread among invertebrate eukaryotes, especially in the higher plant kingdom, where these genetic elements are unusually common and heterogeneous in their sequence. The phylogenetic data also suggest that the present day spectrum of Ty1-copia group retrotransposons has been influenced both by divergence during vertical transmission down evolving lineages and by horizontal transmission between distantly related species. Lastly, the factors affecting Ty1-copia group retrotransposon copy number and sequence heterogeneity in eukaryotic genomes and the effects of transpositional quiescence and defective retrotransposons upon evolution of Ty1-copia group retrotransposons are discussed.
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    Journal of bioenergetics and biomembranes 24 (1992), S. 415-424 
    ISSN: 1573-6881
    Keywords: ATPases ; evolution ; eukaryotes ; endomembranes ; archaebacteria ; progenote ; bioenergetics ; flagella assembly ; endosymbiont theory
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Physics
    Notes: Abstract Proton pumping ATPases/ATPsynthases are found in all groups of present-day organisms. The structure of V- and F-type ATPases/ATP synthases is very conserved throughout evolution. Sequence analysis shows that the V- and F-type ATPases evolved from the same enzyme already present in the last common ancestor of all known extant life forms. The catalytic and noncatalytic subunits found in the dissociable head groups of the V/F-type ATPases are paralogous subunits, i.e., these two types of subunits evolved from a common ancestral gene. The gene duplication giving rise to these two genes (i.e., encoding the catalytic and noncatalytic subunits) predates the time of the last common ancestor. Mapping of gene duplication events that occurred in the evolution of the proteolipid, the noncatalytic and the catalytic subunits, onto the tree of life leads to a prediction for the likely subunit structure of the encoded ATPases. A correlation between structure and function of V/F-ATPases has been established for present-day organisms. Implications resulting from this correlation for the bioenergetics operative in proto-eukaryotes and in the last common ancestor are presented. The similarities of the V/F-ATPase subunits to an ATPase-like protein that was implicated to play a role in flagellar assembly are evaluated. Different V-ATPase isoforms have been detected in some higher eukaryotes. These data are analyzed with respect to the possible function of the different isoforms (tissue specific, organelle specific) and with respect to the point in their evolution when these gene duplications giving rise to the isoforms had occurred, i.e., how far these isoforms are distributed.
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    Genetic resources and crop evolution 39 (1992), S. 9-22 
    ISSN: 1573-5109
    Keywords: Cuba ; evolution ; genetic resources ; homegarden ; in situ conservation ; landraces
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Cuban homegardens are called ‘conucos’. On the basis of new case studies additional information is provided about these ‘conucos’, their history, composition and importance. They and other gardens of similar type are characterized as suitable environment for in situ conservation and for the continuation of evolutionary processes.
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  • 36
    ISSN: 1573-5060
    Keywords: chemical defense ; Colorado potato beetle ; Empoasca fabae ; Epitrix cucumeris ; evolution ; germplasm ; green peach aphid ; insect resistance ; Leptinotarsa decemlineata ; Macrosiphum euphorbiae ; morphology ; Myzus persicae ; potato aphid ; potato flea beetle ; potato leafhopper ; relationship ; Solanum ; taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The past 25 years, 1686 potato accessions, representing 100 species in the genus Solanum L., subgenus Potatoe, section Petota, were evaluated for field resistance to one or more of the following insect pests: green peach aphid, Myzus persicae (Sulzer); potato aphid, Macrosiphum euphorbiae (Thomas); Colorado potato beetle, Leptinotarsa decemlineata (Say); potato flea beetle, Epitrix cucumeris (Harris); and potato leafhopper, Empoasca fabae (Harris). Accessions highly resistant to green peach aphid were identified within 36 species, to potato aphid within 24 species, to Colorado potato beetle within 10 species, to potato flea beetle within 25 species, and to potato leafhopper within 39 species. Resistance levels were characteristic within Solanum species. Insect resistance appears to be a primitive trait in wild potatoes. Susceptibility was most common in the primitive and cultivated Tuberosa. Insect resistance was also characteristic of the most advanced species. The glycoalkaloid tomatine was associated with field resistance to Colorado potato beetle and potato leafhopper. Other glycoalkaloids were not associated with field resistance at the species level. Dense hairs were associated with resistance to green peach aphid, potato flea beetle, and potato leafhopper. Glandular trichomes were associated with field resistance to Colorado potato beetle, potato flea beetle, and potato leafhopper. Significant correlations between insect score and altitude of original collection were observed in six of thirteen species. Species from hot and arid areas were associated with resistance to Colorado potato beetle, potato flea beetle, and potato leafhopper. Species from cool or moist areas tended to be resistant to potato aphid.
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  • 37
    ISSN: 1573-5168
    Keywords: larval lampreys ; exocrine pancreas ; lipase ; amylase ; chymotrypsin ; trypsin ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The activities of trypsin (EC 3.4.21.4), chymotrypsin (EC 3.4.21.1), lipase (EC 3.1.1.3) and amylase (EC 3.2.1.1) were measured in different regions of the alimentary tract of ammocoetes from each of the three extant lamprey families. In the southern hemisphere speciesGeotria australis (Geotriidae), and even more particularlyMordacia mordax (Mordaciidae), enzymatic activity was almost entirely confined to prominent diverticular extensions which arise at the oesophageal-intestinal junction. However, in the holarcticLampetra richardsoni (Petromyzontidae), which does not possess a diverticulum, the enzymatic activity was highest in the upper anterior intestine. It is not clear whether the presence of significantly higher amylolytic and lower lipolytic activities in the diverticulum ofG. australis than in the exocrine tissue of the other two species reflects interspecific differences in the composition of their diets. The capacity of exocrine tissue extracts for chymotryptic and tryptic digestion was assayed before and afterin vitro exposure to trypsin and enteropeptidase, their respective catalytic activators. Prior to exposure to these exogenous activators, both proteolytic enzymes were fully active inL. richardsoni, partially active inG. australis and totally inactive inM. mordax. Maximal chymotryptic activity was greater inM. mordax than inL. richardsoni andG. australis. In contrast, maximal tryptic activity was greater inL. richardsoni than inG. australis and was very low inM. mordax. Since trypsin is the only known activator of chymotrypsinogen, the negligible activity of trypsin inM. mordax would appear anomalous unless a trypsin inhibitor is present in the protopancreas of this species. Differences in the distribution of enzymatic activity within the alimentary tract of the three species is discussed in relation to proposed phylogenetic relationships amongst the extant lamprey families.
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    Human evolution 7 (1992), S. 41-47 
    ISSN: 1824-310X
    Keywords: evolution ; origin of man ; nature and essence of humanity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract It is proposed that the peculiarity of the specific nature of man consists in his polarisation into an ape-like «Australopithecoid» and specifically human sides. Its possible origin, as well as, differences between the concepts of the taxonomic distinction, species specific nature and essence of man are discussed.
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    Human evolution 7 (1992), S. 25-31 
    ISSN: 1824-310X
    Keywords: Epigenesis ; evolution ; history
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    Human evolution 7 (1992), S. 85-91 
    ISSN: 1824-310X
    Keywords: Japan ; Japanese ; evolution ; microevolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The trends in evolutionary research in Japan have largely changed through the introduction of new methodologies such as molecular genetics and multivariate statistics since the 1960’s. The development of ecology and primatology brought another new wave into fields of physical anthropology. This paper reviews briefly general trends in anthropological research now on-going in Japan. Microevolutionary studies of the Japanese and neighboring populations which have a long history in Japan will be reviewed in more detail.
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    Evolutionary ecology 6 (1992), S. 1-14 
    ISSN: 1573-8477
    Keywords: evolution ; habitat selection ; life history ; litter size ; Ontario ; Peromyscus ; seasonality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Analysis of 6 years' data on a population of free-living white-footed mice documents both phenotypic and environmental control of litter size. Litter size was positively correlated with maternal body size. Maternal size depended upon both seasonal and annual variation. Paradoxically, the proportion of small versus large litters varied among habitats independently of the effects of body size. The result is an influence of habitat on life history that yields patterns of reproduction and survival opposite to the predictions of demographic theory. The habitat producing the largest litters had a relatively high ratio of adult/juvenile survival. Litter size was small in the habitat where the adult/juvenile survival ratio was smallest. All of these anomalous patterns can be explained through density-dependent habitat selection by female white-footed mice. Life-history studies that ignore habitat and habitat selection may find spurious correlations among traits that result in serious misinterpretations about life history and its evolution.
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