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The Determination of Sex and Polymorphism in Microevolution1

Published online by Cambridge University Press:  31 May 2012

G. Stehr
Affiliation:
Section of Cytology and Genetics, c/o Forest Insect Laboratory, Sault Ste. Marie, Ontario

Abstract

Environmental instabilities may be grouped into three broad categories each with different conseqences for the organism which has to survive the stress of these instabilities. On one side are irreversible changes of the environment which will lead to complete adaptive compliance or conformity of the population, brought about by natural selection. On the other side are short-term recurrent instabilities, fluctuations, or oscillations; if their cycle is short enough so that all phases are experienced by all individuals of each generation, natural selection will promote the ability of each individual to withstand the whole range of environmental recurrent fluctuations. Between these extremes are recurrent instabilities that are not experienced by all individuals, or by each generation; here natural selection will evolve mechanisms that prevent the population from conforming with any temporary selection pressure. Polymorphism is such a mechanism, specifically polymorphism based on a gene potency balance system modelled on the same principles as the system that determines sex, the most common example of polymorphism. Instances of such polymorphism in a genus of tortricid moths include haemolymph pigment, adult wing colour, and rate of larval development. The latter exemplifies polymorphism of a quantitative character.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1964

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References

Ford, E. B. 1953. The genetics of polymorphism in Lepidoptera. Biol. Rev. 12: 461503.CrossRefGoogle Scholar
Ford, E. B. 1961. The theory of genetic polymorphism. Symp. R. ent. Soc. Lond. 1: 1119.Google Scholar
Hansen-Melander, E., and Melander, Y.. 1963. Sex-chromosome dimorphism in germline and soma. Hereditas 49: 4860.CrossRefGoogle Scholar
Harvey, G. T. 1957. The occurrence and nature of diapause-free development in the spruce budworm, Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae). Canad. J. Zool. 35: 549572.CrossRefGoogle Scholar
Hovanitz, W. 1953. Polymorphism and evolution. Symp. Soc. exp. Biol. 7: 238253. Cambridge Univ. Press.Google Scholar
Mather, K. 1955. Polymorphism as an outcome of disruptive selection. Evolution 9: 5261.CrossRefGoogle Scholar
Richards, O. W. 1961. An introduction to the study of polymorphism in insects. Symp. R. ent. Soc. Lond. 1: 110.Google Scholar
Sheppard, P. M. 1961a. Some contributions to population genetics resulting from the study of the Lepidoptera. Advanc. Genet. 10: 165216.CrossRefGoogle Scholar
Sheppard, P. M. 1961b. Recent genetical work on polymorphic mimetic Papilios. Symp. R. ent. Soc. Lond. 1: 2029.Google Scholar
Siegel, S. 1956. Nonparametric statistics for the behavioral sciences. McGraw-Hill Book Co., New York, Toronto, London.Google Scholar
Stehr, G. 1954. A laboratory method for rearing the spruce budworm, Choristoneura fumiferana (Clem.). Canad. Ent. 86: 423428.CrossRefGoogle Scholar
Stehr, G. 1955. Brown female — A sex-linked and sex-limited character. J. Hered. 46: 263266.CrossRefGoogle Scholar
Stehr, G. 1959. Hemolymph polymorphism in a moth and the nature of sex-controlled inheritance. Evolution 13: 537560.CrossRefGoogle Scholar
Watt, K. E. F. 1963. Dynamic programming, “look-ahead programming” and the strategy of insect pest control. Canad. Ent. 95: 525536.CrossRefGoogle Scholar
Wigglesworth, V. B. 1961. Insect polymorphism — a tentative synthesis. Symp. R. ent. Soc. Lond. 1: 103113.Google Scholar