Journal ArticleDOI
Genetic response to environmental heterogeneity.
Reads0
Chats0
TLDR
Results are reported from an experiment designed to test the hypothesis that different genetic variants are favoured in different environmental niches, in which populations of Drosophila were exposed to experimental environments of various degrees of heterogeneity.Abstract:
ONE of the major problems of contemporary population genetics is how to account for the large amount of genetic variation occurring in natural populations. Considerable controversy exists between those people proposing that the variation is adaptively neutral, and those arguing that most of the variation is maintained by balancing selection. One of the processes of balancing selection postulated, is based on the idea that different genetic variants are favoured in different environmental niches. We report results from an experiment designed to test this hypothesis in which populations of Drosophila were exposed to experimental environments of various degrees of heterogeneity. The rationale is simple—if genetic variation is adaptively neutral, all populations should maintain about the same amount of genetic variation; if the ‘environmental heterogeneity’ hypothesis is correct, the degree of genetic variation in a population should be correlated with the degree of heterogeneity of its environment.read more
Citations
More filters
Journal ArticleDOI
Genotype-environment interaction and the evolution of phenotypic plasticity.
Sara Via,Russell Lande +1 more
TL;DR: These models utilize the statistical relationship which exists between genotype‐environment interaction and genetic correlation to describe evolution of the mean phenotype under soft and hard selection in coarse‐grained environments.
Journal ArticleDOI
Genetic variation in natural populations: patterns and theory.
TL;DR: Analysis of allozymic variation in natural populations of plants, animals, and humans based on studies published prior to early 1976 and involving 243 species, suggests that the amounts of genetic polymorphism and heterozygosity vary nonrandomly between loci, populations, species, habitats, and life zones, and are correlated with ecological heterogeneity.
Journal ArticleDOI
Relationships Between Life History Characteristics and Electrophoretically Detectable Genetic Variation in Plants
TL;DR: It is found that habitat generalists and animal species with cosmopolitan or tropical distributions were typically more variable than species with specialized habitat preferences or temperate distributions.
Book ChapterDOI
The Evolutionary Significance of Genetic Diversity: Ecological, Demographic and Life History Correlates
TL;DR: The evolutionary significance of genetic diversity of proteins in nature remains controversial despite the numerous protein studies conducted electrophoretically during the last two decades.
Journal ArticleDOI
Genetic polymorphism in heterogeneous environments: a decade later
TL;DR: The purpose of this review is to evaluate the research of the intervening decade on genetic polymorphism in variable environments and to review the theoretical developments in the past decade.
References
More filters
Book
Genetics and the Origin of Species
TL;DR: In this article, the authors present a taxonomy of diverse and diverse populations in the United States, including the following: 1.ORGANIC DIVERSITY 3 GENE MUTATION 15 MUTation as a basis for RACIAL and SPECIFIC DIFFERENCES 39 CHROMOSOMAL CHANGES 73 VARIATION in NATURAL POPULATION 118 SELECTION 149 POLYPLOIDY 192 ISOLATING MECHANISMS 228 HYBRID STERILITY 259 SPECIES AS NATUREAL UNITS 303 L
Journal ArticleDOI
Genetic Equilibrium When More Than One Ecological Niche is Available
TL;DR: The question arose of whether it was in fact possible to have equilibrium without the heterozygote being superior to both homozygotes in any single niche and it is shown below that under certain assumptions the answer is yes.
Journal ArticleDOI
Enzyme variability in the drosophila willistoni group. iv. genic variation in natural populations of drosophila willistoni
TL;DR: The observations support the conclusion that balancing natural selection is the major factor responsible for the considerable genetic variation observed in D. willistoni.
Journal ArticleDOI
Polymorphism as an outcome of disruptive selection
TL;DR: Polymorplhism would seem to be a possible alternative to isolation as an outcome of disruptive selection, acting under conditions and in ways which the authors shall now examine; and being an alternative it is not necessarily a step on the way to isolation, even though both spring from the same type of selection.