Journal ArticleDOI
Enzyme Polymorphism and Biosystematics: The Hypothesis of Selective Neutrality
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TLDR
An examination of the possible role of selection in maintaining enzyme polymorphisms in natural populations with respect to electrophoretic variation at enzyme loci is addressed.Abstract:
In the last few years there has been an explosion of information concerning electrophoretic variation at enzyme loci. These data are being increasingly employed in attempts to elucidate biosystematic and phylogednetic relationships. As the evolutionary role of these allozyme polymorphisms is not well understood, the assumptions inherent in such approaches warrant careful consideration. The following review addresses itself to an examination of the possible role of selection in maintaining enzyme polymorphisms in natural populations. Selected for discussion here are those papers which seem to me to bear importantly upon central issues; the literature citations are not intended to be comprehensive or complete. EXPERIMENTAL ASPECTS OF ELECTROPHORETIC ANALYSIS Before discussing either the patterns of allozyme variation which have been observed or their possible evolutionary significance, it is necessary to consider what has been examined: the classes of protein variants detectable by current methods, the organisms which have been examined for such variants, and the enzyme reactions which have been used as screens. It is necessary to state carefully the experimental question which allozyme surveys pose in order to evaluate possible limitations and bias in the results obtained. Experimental approaches involving electrophoretic analysis have dealt with three related sorts of questions: (a) those concerning relative amounts of variation; (b) those concerning the genetic nature of polymorphic variation; (c) those employing comparisons of variant types. Work in each of these areas may entail important assumptions about the nature of the variation. When assessing the levels of electrophoretic variation in a natural population, the assumption is generally made, implicitly or explicitly, that electrophoretically deread more
Citations
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The search for a general theory of behavior
TL;DR: In this paper, the authors combine the approaches and data of biologists and social scientists in analyzing reciprocity in social interactions, considering six principal aspects: group-living, sexual competition, incest avoidance, nepotism, reciprocity, and parenthood.
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Sample sizes required to detect linkage disequilibrium between two or three loci.
TL;DR: Estimates of the degree of nonrandom association among genes (linkage disequilibrium) can provide evidence of the role of natural selection in maintaining allozyme polymorphisms in natural populations and the maximum likelihood procedures for such estimates based on gametic or zygotic frequencies at the level of two loci are outlined.
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Geographic protein variation and divergence in populations of the salamander plethodon cinereus.
TL;DR: The red-backed salamander Plethodon cinereus (Green) is the most widely distributed member of a group in which morphological divergence is limited and there has been no satisfactory resolution of the evolutionary relationships among its populations.
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Evolution of Phenotypic Diversity in Gasterosteus Aculeatus Superspecies on the Pacific Coast of North America
TL;DR: A conceptual model for the evolution of phenotypic diversity of the threespine stickleback on the Pacific coast of North America is presented and it is found that in Gasterosteus aculeatus, in the absence of gene flow for periods sufficient to allow Morphological divergence, morphological divergence seems almost inevitable but usually is held within well defined limits.
References
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Journal ArticleDOI
Genetic distance between populations
TL;DR: If enough data are available, genetic distance between any pair of organisms can be measured in terms of D, and this measure is applicable to any kind of organism without regard to ploidy or mating scheme.
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Evolution in Mendelian Populations.
TL;DR: Page 108, last line of text, for "P/P″" read "P′/ P″."
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Evolutionary Rate at the Molecular Level
TL;DR: Calculating the rate of evolution in terms of nucleotide substitutions seems to give a value so high that many of the mutations involved must be neutral ones.