Team DeNardo

Emily Taylor

Education:

B.A. English, 1998, University of California, Berkeley (UC Berkeley)

Ph.D. Biology, 2005, Arizona State University

Current Position:

Assistant Professor, Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, CA 93407.

Email:

etaylor@calpoly.edu

Web site:

http://bio.calpoly.edu/Faculty/Taylor.html

Research Interests:

My research interests are environmental physiology, natural history, and conservation of reptiles. I am particularly interested in how environmental and hormonal mechanisms affect the processes of growth and reproduction, and ultimately, sexual size dimorphism.

Dissertation Work:

My dissertation research addressed the question, "Why are male rattlesnakes larger than females?" from a mechanistic, physiological viewpoint. My research involved theoretical ideas and techniques from many disciplines, including physiological ecology, endocrinology, and evolutionary biology.

I addressed my research question using a combination of field and laboratory approaches. I studied free-ranging Western Diamond-backed Rattlesnakes (Crotalus atrox) at our field site for four years using radiotelemetry and mark-recapture, and I conducted several laboratory experiments to examine specific factors in a controlled setting. Specific topics I investigated include:

· reproductive ecology and natural history

· hormonal regulation of reproduction

· thermal biology

· effects of food supplementation on reproduction

· growth plasticity of snakes in the lab

· effects of castration on growth

Overall, I found that growth is extremely plastic in C. atrox, with food intake and the energetic cost of reproduction heavily influencing growth. Testosterone does not appear to affect growth in this species, as it does in many other vertebrates. It appears that male C. atrox are larger than females primarily due to differential energy expenditure on reproduction, in which females expend much more energy on reproduction than males, resulting in less energy left over for growth. In a food-limited environment such as the Sonoran Desert, this differential energy expenditure can have profound effects on adult body size and sexual size dimorphism.

Past Research:

As an undergraduate at the University of California at Berkeley, I conducted a research project with Dr. Harry Greene on the feeding habits of the Baja California Rattlesnake.

Publications

1. Taylor, E. N. 2001. Diet of the Baja California rattlesnake, Crotalus enyo (Viperidae). Copeia 2001:552-554. (already linked on DeNardo web site)

2. Lourdais, O., X. Bonnet, R. Shine and E. N. Taylor. 2003. When does a reproducing female viper (Vipera aspis) "decide" on her litter size? Journal of Zoology London 259:123-129.

3. Taylor, E. N. and G. W. Schuett. 2004. Effects of temperature and storage duration on the stability of steroid hormones in blood samples from Western Diamond-backed Rattlesnakes. Herpetological Review 35:14-17.

4. Taylor, E. N., D. F. DeNardo, and D. H. Jennings. 2004. Seasonal steroid hormone levels and their relation to reproduction in the Western Diamond-backed Rattlesnake, Crotalus atrox (Serpentes: Viperidae). General and Comparative Endocrinology 136:328-337.

5. Taylor, E. N., D. F. DeNardo, and M. A. Malawy. 2004. A comparison between point- and semi-continuous sampling for assessing body temperature in a free-ranging ectotherm. Journal of Thermal Biology 29:91-96.

6. Schuett, G. W., E. N. Taylor, E. A. Van Kirk, and W. J. Murdoch. 2004. Handling stress and plasma corticosterone levels in captive male Western Diamond-backed Rattlesnakes (Crotalus atrox). Herpetological Review 35:229-233.

7. Taylor, E. N. and D. F. DeNardo. 2005. Reproductive Ecology of Western Diamond-backed Rattlesnakes (Crotalus atrox) in the Sonoran Desert. Copeia 2005:152-158.

8. Taylor, E. N. and D. F. DeNardo. 2005. Sexual size dimorphism and growth plasticity in snakes: an experiment on the Western Diamond-backed Rattlesnake (Crotalus atrox). Journal of Experimental Zoology 303A:598-607.

9. Taylor, E. N., M. A. Malawy, D. M. Browning, S. V. Lemar, and D. F. DeNardo. 2005. Effects of food supplementation on the physiological ecology of the Western Diamond-backed Rattlesnake (Crotalus atrox). Oecologia. In press.