The role of frequency-dependent selection in the outcome of experimental populations in evolution

✍ Scribed by D. Anxolabéhère; G. Périquet

• Publisher: Springer Netherlands
• Year: 1981
• Tongue: English
• Weight: 569 KB
• Volume: 55
• Category: Article
• ISSN: 0016-6707
• DOI: 10.1007/bf00133995

✦ Synopsis

In this paper, the equilibrium states obtained by two kinds of models involving frequency-dependent selection at one locus are analyzed in order to explain the experimental evolution usually attributed to the interaction between the locus studied and another, uncontrolled, locus.

Under linear allelic frequency-dependent selection, only one stable equilibrium may be obtained and cases with two stable equilibria require at least a quadratic frequency-dependent model. The latter leads to a maximum of three equilibria where only two situations are possible: an unstable equilibrium being found between two stable ones or, inversely, a stable equilibrium between two.unstable ones. Numerical examples are proposed to discuss cases of biological interest such as the advantage of the rarest genotype and to draw attention to some misleading interpretations arising from the linearization of fitness curves. Finally, the results of evolution in some experimental populations that lead to different equilibria are discussed and an explanation of them is proposed without invoking selection at a second locus.