My research concerns the natural selection of social behavior. Emphasizing quantitative and experimental approaches in the study of natural populations, I am interested in sexual selection, the economy and evolution of mating systems, spatial dispersion, and communication.

I am currently conducting a field and laboratory investigation of sexual selection in a group of passerine birds in Australia, the fairy-wrens. Fairy-wrens live in socially-monogamous groups, but most individuals mate promiscuously with individuals from other groups. Using a combination of field observations, direct manipulation of group size and composition, and DNA fingerprinting analysis of parentage, I am studying both the evolutionary causes and consequences of reproductive promiscuity in five species in this group. In a new study, I am studying taxonomy and phylogenetics in fairy-wrens, testing hypotheses for the evolution of sexual dimorphism in this group.

In addition to field work on birds in Australia, I am involved in theoretical studies of social behavior and decision making in animals, and a local study of population biology and behavior of Monk Parakeets. The underlying themes in these studies are the questions of how interactions among individuals and the mating decisions that individuals make affect the process of sexual selection and the evolution of alternative reproductive tactics.

Projects that my graduate students are currently involved in include: 1) geographical variation and the evolution of toxicity in the genus Pitohui; 2) sexual selection and mating systems in birds; and 3) the evolution of sexual cannibalism.

Recent Publications

Tibbetts, E., and S. Pruett-Jones. 1999.

Habitat and nest-site partitioning in the splendid and variegated fairy-wrens (Aves: Maluridae). Australian Journal of Zoology 47:317-326.

Swaddle, J. P., J. Karubian, and S. Pruett-Jones. 2000.

A novel evolutionary pattern of reversed sexual dimorphism in fairy-wrens: implications for sexual selection. Behavioral Ecology 11:345-349.

South, J., and S. Pruett-Jones. 2000.

Patterns of flock size, diet, and vigilance of naturalized monk parakeets in Hyde Park, Chicago. Condor 102:848-854.

Regosin, J. V., and S. Pruett-Jones. 2001.

Sexual dimorphism in the scissor-tailed flycatcher. Auk, 118:167-175.

Zelano, B., K. A. Tarvin, and S. Pruett-Jones. 2001.

Singing in the face of danger: the anomalous type II song of the splendid fairy-wren. Ethology 107:201-216.

Swaddle, J. P., and S. Pruett-Jones. 2001.

Starlings can categorize symmetry differences in dot displays. American Naturalist 158:300-307.

Driskell, A. C., S. Pruett-Jones, K. A. Tarvin, and S. Hagevik. 2002.

A preliminary analysis of genetic differentiation in the white-winged fairy-wren (Aves: Maluridae). Australian Journal of Zoology, in press.

Swaddle, J. P., S. J. Arnold, and S. Pruett-Jones. 2002.

A test for sexual differences in phenotypic variance. Evolution, in press.