Christine M. Drea
Earl D. McLean Professor
I have two broad research interests, sexual differentiation and social behavior, both focused on hyenas and primates. I am particularly interested in unusual species in which the females display a suite of masculinized characteristics, including male- like or exaggerated external genitalia and social dominance. The study of naturally occurring hormones in such unique mammals can reveal general processes of hormonal activity, expressed in genital morphology, reproductive development, and social behavior. Taking a combined laboratory and field approach allows me to relate captive data to various facets of the animals' natural habitat, thereby enhancing the ecological validity of assay procedures and enriching interpretation in an evolutionary framework. The goal of comparative studies of hyenas and lemurs is to help elucidate the mechanisms of mammalian sexual differentiation.
My research program in social behavior focuses on social learning and group cohesion. Using naturalistic tasks that I present to captive animals in socially relevant contexts, I can investigate how social interaction modulates behavior, problem- solving, and cognitive performance. By studying and comparing models of carnivore and primate foraging, I can better understand how group-living animals modify their actions to meet environmental demands. A primary interest is determining whether similar factors, related to having a complex social organization, influence learning and performance across taxonomic groups. I am also interested in how animals learn rules of social conduct and maintain social cohesion, as evidenced by their patterns of behavioral developmental, the intricate balance between aggression and play, the expression of scent marking, and the social facilitation or inhibition of behavior.
Drea, Christine M. “Sex and seasonal differences in aggression and steroid secretion in Lemur catta: are socially dominant females hormonally 'masculinized'?” Hormones and Behavior, vol. 51, no. 4, Apr. 2007, pp. 555–67. Epmc, doi:10.1016/j.yhbeh.2007.02.006. Full Text
Scordato, E. S., and C. M. Drea. “Scents and sensibility: information content of olfactory signals in the ringtailed lemur, Lemur catta.” Animal Behaviour, vol. 73, no. 2, Feb. 2007, pp. 301–14. Scopus, doi:10.1016/j.anbehav.2006.08.006. Full Text
Glickman, Stephen E., et al. “Mammalian sexual differentiation: lessons from the spotted hyena.” Trends in Endocrinology and Metabolism: Tem, vol. 17, no. 9, Nov. 2006, pp. 349–56. Epmc, doi:10.1016/j.tem.2006.09.005. Full Text
Drea, Christine M. “Studying primate learning in group contexts: Tests of social foraging, response to novelty, and cooperative problem solving.” Methods (San Diego, Calif.), vol. 38, no. 3, Mar. 2006, pp. 162–77. Epmc, doi:10.1016/j.ymeth.2005.12.001. Full Text
Drea, C. M. “Morphological and hormonal correlates of 'masculinization' in ringtailed lemurs (Lemur catta).” American Journal of Physical Anthropology, WILEY-LISS, Jan. 2006, pp. 85–85.
Drea, Christine M. “Bateman revisited: the reproductive tactics of female primates.” Integrative and Comparative Biology, vol. 45, no. 5, Nov. 2005, pp. 915–23. Epmc, doi:10.1093/icb/45.5.915. Full Text
Drea, Christine M., et al. “Responses to olfactory stimuli in spotted hyenas (Crocuta crocuta): I. Investigation of environmental odors and the function of rolling.” Journal of Comparative Psychology (Washington, D.C. : 1983), vol. 116, no. 4, Dec. 2002, pp. 331–41. Epmc, doi:10.1037/0735-7036.116.4.331. Full Text
Drea, Christine M., et al. “Responses to olfactory stimuli in spotted hyenas (Crocuta crocuta): II. Discrimination of conspecific scent.” Journal of Comparative Psychology (Washington, D.C. : 1983), vol. 116, no. 4, Dec. 2002, pp. 342–49. Epmc, doi:10.1037/0735-7036.116.4.342. Full Text
Place, Ned J., et al. “Effects of prenatal treatment with antiandrogens on luteinizing hormone secretion and sex steroid concentrations in adult spotted hyenas, Crocuta crocuta.” Biology of Reproduction, vol. 67, no. 5, Nov. 2002, pp. 1405–13. Epmc, doi:10.1095/biolreprod.102.004226. Full Text
Drea, C. M., et al. “Exposure to naturally circulating androgens during foetal life incurs direct reproductive costs in female spotted hyenas, but is prerequisite for male mating.” Proceedings. Biological Sciences, vol. 269, no. 1504, Oct. 2002, pp. 1981–87. Epmc, doi:10.1098/rspb.2002.2109. Full Text