Welcome to The Department of Biological Sciences!

The department consists of a lot of people: faculty, administrative staff, technical staff, and graduate research/teaching assistants. One strong thing bonding us together is that we are working hard at things we really like, advanced biological education and research.

There is a lot to see on this website, so look around. You can get a very good overview of our research endeavors by visiting the web pages of the individual faculty members and their research labs. If you are a current or prospective undergraduate student, you will find detailed descriptions of our various majors, information about our courses and undergraduate research, and links to interdisciplinary opportunities. If you are looking around for opportunities at the graduate level, peruse the pages describing our doctoral programs in molecular cell biology, biochemistry, and integrative biology and neuroscience, or our highly focused master's program in molecular biology that is exclusively by distance.

If you have questions about any aspects of our department, feel free to e-mail any faculty member or post-doctoral scientist, or any member of our administrative or technical staff. Anyone will be glad to answer your questions or put you in touch with someone who can.

Candice Klingerman Ph.D. Candidate

Estrogens, one of the active components of most birth control pills, are naturally occurring hormones important for reproductive function and general health. Candice Klingerman and her mentor, Professor Jill Schneider, suspect that during evolution, a major function of estrogens has been to orchestrate the appetites for food and sex in a way that allows animals to optimize their reproductive success in environments where energy availability fluctuates.  When animals must work for their food, low levels of estradiol increase the appetite for food, and thereby ensure vigilant foraging and eating.  High levels of estradiol (such as those that occur at the time of ovulation) decrease the urge to forage and eat while simultaneously increasing the urge for sexual adventure. 

Klingerman’s work with Syrian hamsters shows that after a period of food insecurity (limited food availability), hamsters spend most of the available time foraging and hoarding while ignoring the male hamsters that try to court them.  Food-limited females are fixated on food until their estradiol levels rise, at which time they become more interested in male hamsters.  At the time of ovulation and highest estradiol secretion, female hamsters become fixated on males and show little interest in food.  These wild fluctuations in behavioral priorities are only apparent in hamsters that are energetically challenged. In contrast, females with all the food they want, and little opportunity for exercise, do not fluctuate in their appetites for food and sex.  They prefer sexual stimuli on all days of their estrous cycle.  Similarly, women who are not on diets have little fluctuation in appetite over the menstrual cycle, whereas women on calorie-restricting diets find it very difficult to stay on their diets during the second half of their menstrual cycles, when estrogen levels are low.  Other studies show that women are most likely to take sexual risks around the time of ovulation.  Our research suggests that this menstrual fluctuation in sexual appetite would be greater in women who are dieting or binge eating.

The interaction between energy availability and estradiol, allows Klingerman to explore the underlying physiological mechanisms. For example, correlated with effects of food restriction on the preference for sexual vs. food stimuli, Klingerman finds changes in a brain peptide RFamide-RP-3 (in collaboration with members of the Kriegsfeld laboratory at University of California, Berkeley).  In contrast, these mild metabolic challenges did not increase the activation of neurons in the mesolimbic dopamine system, a brain area involved in reward.  Research in progress examine other hormones that have formerly been seen as “satiety” or “feeding” hormones.

Candice’s research is relevant for understanding obesity, diabetes, fertility and sexual libido.  Candice has published four peer-reviewed manuscripts from her master’s and doctoral research and has received The Gorden C. Thorne Fellowship from the Department of Biological Sciences and a research grant from Sigma Xi.

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Department of Biological Sciences
Lehigh University
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