Ecological co-optation in birds

Aköz, Gökçe
Natural selection is commonly thought as the engine of ecological diversification, where sexual selection has a secondary role in promoting speciation. Sexual selection is also attributed a primary role in the origin of species, where it produces divergence not in ecological traits, but in sexually selected traits. Ecological co-optation suggests an alternative to these prevailing ideas. Sexual selection alone could drive ecological diversification, where a sexually selected trait is co-opted for a novel viability trait. Such an ecological co-optation will then enable species with newly co-opted trait to exploit a novel niche. In the present study, we test the prediction of ecological co-optation in antbirds, tanagers, and blackbirds. We use sexually selected plumage coloration in these groups, and check whether the birds with colorful plumage differ in their niche use (i.e. habitat range, altitudinal range, and distributional range), by using phylogenetically independent contrasts method, and sister taxa comparisons. Our results show that increasing plumage coloration produces changes in niche uses. Similarly, increasing plumage color differences between sexes leads to changes in niche width, which is a trend consistent with ecological co-optation hypothesis.
Citation Formats
G. Aköz, “Ecological co-optation in birds,” M.S. - Master of Science, Middle East Technical University, 2013.