DISSERTATION RESEARCH: Ornament evolution in Anolis lizards: the interaction between survival and reproductive selection in a manipulative field experiment with replication

Harvard University, Cambridge MA

Investigators

Abstract

Animals that attract mates using visual signals are casting their message into a world full of hostile entities - predators, prey, competitors - all of which are eager to intercept their message. Creating signals that will capture the attention of the intended target without attracting unwanted attention is a constant challenge for wild animals. The objective of this study is to uncover how variation in signal color influences how competing selective forces act on the individual using lizards in the neotropical genus Anolis. Specifically, the ornament color of males in the wild will be manipulated to see how this affects individual survival and reproductive success. Another component of this study will be to determine how an individual's outcome can change depending on population-level variation in the strength of competition, which will be altered by manipulating the sex ratio in six experimental populations. This study will help elucidate how several competing forces can act in conflict or in concert to shape animal signals, a key question in the study of ecological and evolutionary biology. The diversity of animal signals, especially visual signals, is thought to be an important force in creating species diversity; the results of this research may therefore also contribute to our understanding of how natural processes create and maintain species diversity.