Meeting Abstract
With this artificial selection experiment, we want to quantify the effects of two sexual selection mechanisms on the male phenotype in guppies. Secondary sexual traits in males are the result of a range of selection mechanisms acting on them, pushing traits in one or another direction. The outcome depends on the relative contribution of i.a. the two main sexual selection mechanisms: intra- and intersexual selection, namely male-male competition and female mate choice. In guppies (Poecilia reticulata), epigamic selection is believed to be the dominant evolutionary force in the elaboration of male ornaments, but agonistic interactions between males have been underestimated. In this study, we have set up breeding lines to test the individual effects of intra- and intersexual selection on male phenotypes, without possible mutual interference. A random breeding line was also maintained. We test effects after 5 generations on male appearance and behaviour, and test whether both evolutionary forces shape traits in the same way, and whether female preferences evolve accordingly within treatments.
