Effects of sexual selection and viability selection on a chromosomal inversion polymorphism

#posted by Maren Wellenreuther

Dear all,
sorry for the late posting. At next week's EXEB lab meeting we will dive into the world of seaweed flies and discuss a recent paper by Edward and Gilburn on the interaction of sexual selection and viability selection on the maintenance of a large chromosomal inversion polymorphism. Hanna Rosenquist will present the paper.

Evolution. 2013 Jan;67(1):295-302. doi: 10.1111/j.1558-5646.2012.01754.x. Epub 2012 Aug 27.
Male-specific genotype by environment interactions influence viability selection acting on a sexually selected inversion system in the seaweed fly, Coelopa frigida.
Edward DA, Gilburn AS.

Abstract
In the seaweed fly, Coelopa frigida, a large chromosomal inversion system is affected by sexual selection and viability selection. However, our understanding of the interaction between these two selective forces is currently limited as research has focused upon a limited range of environments. We allowed C. frigida larvae to develop in two different algae, Fucus and Laminaria, and then measured viability and body size for each inversion genotype. Significant male-specific genotype-by-environment interactions influenced viability and body size. For males developing in Laminaria, the direction of viability selection acts similarly on the inversion system as the direction of sexual selection. In contrast, for males developing in Fucus, viability selection opposes sexual selection. These results demonstrate that through considering viability selection in different environments, the costs and benefits associated with sexual selection can be found to vary.