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David Westneat


Ph.D. Univ. of North Carolina, 1986
B.A. Carleton College, 1981


Behavioral ecology: I am interested in the biology of social behavior, particularly the interactions between the sexes in birds. This is fascinating because such inetractions are often a mix of cooperation and conflict. Their study demands integration across multiple levels of biological organization and requires a diversity of approaches. I like the conceptual challenges of understanding the ecological causes and evolutionary consequences of social interactions. I also enjoy the insights gained by employing different techniques to answer a particular question. My program involves detailed observations of the behavior of free-living animals, use of molecular and biochemical techniques to uncover processes linked to mating interactions, experimental manipulations of key ecological and social factors, and empirical and theoretical work on the developmental and mechanistic processes producing behavior. Three major phenomena are being studied in my lab (you can learn more by going to my lab web page):

Extra-pair paternity in birds

For most of my career, I have focused on three main questions about avian reproductive behavior: (1) the tradeoff for males between the benefits of pursuing additional copulations versus the benefits of paternal care, (2) the factors influencing female behavior during attempted copulations by both the social mate and extra-pair males, and (3) the consequences of these copulations for the process of sexual selection. I have been studying these questions in red-winged blackbirds and house sparrows, with my students using either those systems or developing their own.

Development and function of plumage signals

I have also been interested in how male and female social interactions in a variety of contexts affect reproductive behavior, how signals might be involved in such interactions, and the underlying physiological, psychological, and developmental processes leading to signal production by the signaler and decision-making by the receiver. House sparrows, with their sexually dimorphic plumage, have been the focus of most of my recent work on these topics.

Personality, plasticity, and the nature of phenotypic variation 

I have recently begun an array of studies investigating the interplay between personality and plasticity, which are elements to a broader understanding of the hierarchical nature of phenotypic variation. Behavior is particularly fascinating because it can vary among species, among populations within species, among individuals, and within individuals. Within-individual variation can be due to phenotypic plasticity, but could also come from stochastic processes. There is the possibility that stochastic variation could differ between individuals or within-individuals via adpative flexibility (e.g., variance sensitivity). I am currently using parental care in house sparrows to explore the ecological causes, proximate mechanisms, and the selective forces affecting the nature of phenotypic variation.