Hostname: page-component-8448b6f56d-c4f8m Total loading time: 0 Render date: 2024-04-25T00:26:45.281Z Has data issue: false hasContentIssue false
  • English
  • Français

Genetic variation in varying environments

Published online by Cambridge University Press:  14 April 2009

Trudy F. C. Mackay
Trudy F. C. Mackay
Affiliation:
Institute of Animal Genetics, West Mains Road, Edinburgh EH9 3JN
Rights & Permissions [Opens in a new window]

Summary

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

In order to assess the relationship between genetic and environmental variability, a large natural population of Drosophila melanogaster was replicated as eight subpopulations, which were subjected to four different patterns of environmental variation. The environmental variable imposed was presence of 15% ethanol in the culture medium. Experimental treatments of the populations were intended to simulate constant environmental conditions, spatial heterogeneity in the environment, and two patterns of temporal environmental variation with different periodicity (long- and short-term temporal variation). Additive genetic and phenotypic variation in sternopleural and abdominal chaeta number, and body weight, were estimated in two successive years, and measurements were taken of the genotype–environment correlation of body weight and sternopleural bristle score with medium type.

Additive genetic variance of sternopleural chaeta number and of body weight was significantly greater in the three populations experiencing environmental heterogeneity than in the control population, but additive genetic variance of abdominal bristle score was not clearly affected by exposing populations to varying environments. Temporal environmental variation was equally, if not more, efficient in promoting the maintenance of genetic variation than spatial heterogeneity, but the cycle length of the temporal variation was of no consequence. Specific genotype–environment interactions were not present, therefore adaptation to heterogeneous environments is by selection of heterozygosity per se, rather than by differential survival of genotypes in the alternate niches.

Type
Research Article
Information
Genetics Research , Volume 37 , Issue 1 , February 1981 , pp. 79 - 93
Copyright
Copyright © Cambridge University Press 1981

References

REFERENCES

Beardmore, J. A. (1961). Diurnal temperature fluctuation and genetic variance in Drosophila populations. Nature 189, 162–163.CrossRefGoogle ScholarPubMed
Beardmore, J. A., Dobzhansky, T. & Pavlovsky, O. A. (1960). An attempt to compare the fitness of polymorphic and monomorphic experimental populations of Drosophila pseudoobscura. Heredity 14, 19–33.CrossRefGoogle Scholar
Beardmore, J. A. & Levine, L. (1963). Fitness and environmental variation. I. A study of some polymorphic populations of Drosophila pseudoobscura. Evolution 17, 121–129.CrossRefGoogle Scholar
Bryant, E. H. (1976). A comment on the role of environmental variation in maintaining polymorphisms in natural populations. Evolution 30, 188–190.CrossRefGoogle ScholarPubMed
Felsenstein, J. (1976). The theoretical population genetics of variable selection and migration. Annual Review of Genetics 10, 253–280.CrossRefGoogle ScholarPubMed
Gillespie, J. H. (1974). The role of environmental grain in the maintenance of genetic variation. American Naturalist 108, 831–836.CrossRefGoogle Scholar
Hedrick, P. W. (1974). Genetic variation in a heterogeneous environment. I. Temporal heterogeneity and the absolute dominance model. Genetics 78, 757–770.CrossRefGoogle Scholar
Hedrick, P. W. (1976). Genetic variation in a heterogeneous environment. 1I. Temporal heterogeneity and directional selection. Genetics 84, 145–157.CrossRefGoogle Scholar
Hill, W. G. (1970). Design of experiments to estimate heritability by regression of offspring on selected parents. Biometrics 26, 566–571.CrossRefGoogle ScholarPubMed
Long, T. (1970). Genetic effects of fluctuating temperature in populations of Drosophila melanogaster. Genetics 66, 401–416.CrossRefGoogle ScholarPubMed
Mackay, T. F. C. (1979). Genetic variation in varying environments. Ph.D. thesis, University of Edinburgh.Google Scholar
McDonald, J. F. & Ayala, F. J. (1974). Genetic response to environmental heterogeneity Nature 250, 572–574.CrossRefGoogle ScholarPubMed
Nevo, E. (1978). Genetic variation in natural populations: Patterns and theory. Theoretical Population Biology 13, 121–177.CrossRefGoogle ScholarPubMed
Powell, J. R. (1971). Genetic polymorphism in varied environments. Science 174, 1035–1036.CrossRefGoogle ScholarPubMed
Powell, J. R. & Wistrand, H. (1978). The effect of heterogeneous environments and a competitor on genetic variation in Drosophila. American Naturalist 112, 935–947.CrossRefGoogle Scholar
Reeve, E. C. R. (1955). The variance of the genetic correlation coefficient. Biometrics 11, 357–374.CrossRefGoogle Scholar
Reeve, E. C. R. & Robertson, F. W. (1954). Studies in quantitative inheritance. VI. Sternite chaeta number in Drosophila: a metamerie quantitative character. Molecular and General Genetice 86, 269–288.CrossRefGoogle Scholar
Robertson, A. (1959). The sampling variance of the genetic correlation coefficient. Biometrics 15, 469–485.CrossRefGoogle Scholar
Sokal, R. R. & Rohlf, F. J. (1969). Biometry. W. H. Freeman, San Francisco.Google Scholar
Strobeck, C. (1975). Selection in a fine-grained environment. American Naturalist 109, 419–425.CrossRefGoogle Scholar
Templeton, A. R. (1977). Survival probabilities of mutant alleles in fine-grained environments. American Naturalist 111, 951–966.CrossRefGoogle Scholar
U F A W Handbook on the care and management of laboratory animals. 1967. E. and S. Livingstone, Edinburgh.Google Scholar