DISSERTATION RESEARCH: Mate choice, parasites and immune response in Western bluebirds'

Parasites can influence many aspects of their hosts' lives, including the mates they chose. Animals may mate with less-parasitized individuals, and, by doing so, ensure that genes for parasite resistance are passed on to their offspring. A large body of work has focused on examining how parasites influence mate choice by measuring immune response and determining whether preferred mates have a stronger immune response. This assumes that a stronger immune response results in fewer parasites infecting the host. However, this assumption is rarely tested. Moreover, many studies have found conflicting results, with some reporting that preferred mates have a stronger immune response, while others report the exact opposite result. Dr. Zuk and Ms. Jacobs will clarify the role of immunity in determining parasite levels and mate choice using an experiment conducted on western bluebirds. They will use feeding trials, in which some individuals receive supplemental food, while others are left alone as controls, to examine how immune response influences parasite levels in wild birds. Supplemental food has been shown to allow individuals to mount a stronger immune response; if a strong immune response always results in lower parasite loads, then fed birds should have fewer parasites, and birds with stronger immunity and fewer parasites should be preferred as mates. The investigators will use new molecular methods to accurately measure infection with avian malaria, a common parasite of birds. This project will help researchers better understand what affects immune response and parasite levels in wild animals. Such knowledge has important consequences for human health, as many emerging diseases in humans come from animals. Results of this project will be broadly disseminated using open access journals, and the project itself will provide an opportunity to train undergraduate research assistants in basic field and research techniques.