Meeting Abstract
Over the past decade, evolutionary ecologists have begun to focus on the physiological mechanisms underlying trade-offs among traits. Since von Schantz et al.’s (1999) groundbreaking paper, oxidative stress (OS) biology has become a focal point in the integration of proximate mechanisms with ultimate explanations, and has been especially influential in the study of sexually selected condition-dependent traits. One area of research that has been left behind in the integration of evolution and OS biology is postcopulatory sexual selection—sperm competition and cryptic female choice. It is noteworthy that OS has been linked to infertility in human males for almost twenty years, but very few studies have addressed OS in the context of sperm competition. Here we present data on the effect of whole-body oxidative status on sperm traits and an interaction with a signal trait, brightly colored gular bibs, in painted dragon lizards, Ctenophorus pictus. Furthermore, we test for an interaction effect between exhaustive exercise and the possession of bibs on sperm traits. We demonstrate a link between a signal trait, sperm traits and activity levels.
