ABSTRACT
Department of Biology, University of Virginia, PO Box 400328, Charlottesville, VA 22904 (USA). * Corresponding author
Sexual selection arises from variance in mating success that occurs due to intrasexual (male-male or female-female competition) and intersexual mechanisms (mate choice), as well as from postcopulatory processes (sperm competition, cryptic female choice) that infl uence fertilization success. Lizards fi gure prominently in historical and current research in each of these areas, and much of this work focuses on the role of sexual selection in generating the dramatic sex differences in size, shape, coloration, behavior, physiology, and life history that characterize this group. Sexual dimorphism has also been studied with respect to selection arising from variance in fecundity, and though some defi nitions of sexual selection include fecundity selection (Cornwallis and Uller 2010), we retain the traditional Darwinian distinction between these terms (Darwin 1871; Andersson 1994; Fairbairn et al. 2007). In this chapter, we briefl y review the major patterns of sexual selection in lizards and tuatara, their roles in shaping sexual dimorphism, and the evolutionary dynamics that ensue. Our goal is not to thoroughly review the vast literature on these topics, but to provide a brief overview of the state of the fi eld while highlighting several exiting new directions in which studies of lizards are advancing evolutionary theory. In particular, we focus on lizards as models for the study of intralocus sexual confl ict, alternative reproductive tactics, and speciation.
