Charlyn Partridge

Cryptic gamete choice in the broad-nosed pipefish, Syngnathus typhle
Postcopulatory sexual selection has become a subject of considerable discussion in animal behaviour.  One area that has been much debated over the past few years is the importance of cryptic mate choice, the most controversial form of which is gamete (usually sperm) choice.  Gamete choice is defined as the ability of one sex, usually the female, to bias offspring parentage through its morphology, physiology, or other behaviours that occur after copulation.  Two fundamental questions in mate choice theory are, first, whether or not gamete choice occurs in a wide range of biological systems and, second, whether or not such a mechanism of choice can lead to directional sexual selection.  Here, we use the ability to manipulate perceived female quality in order to determine the importance of cryptic gamete choice in a sex-role reversed pipefish.

Effects of a micropollutant, 17α-ethynylestradiol (EE2), on mate choice and reproductive fitness in the Gulf pipefish, Syngnathus scovelli
Over the past twenty years a number of synthetic compounds have been shown to exhibit estrogen-like activity causing a disruption to specific endocrine pathways; which in turn possess the potential to have a major impact on the reproductive viability of a number of different systems.  The long-term goal of this research is to determine if endocrine disruptors can disrupt sexual selection mechanisms and optimal mate choice behaviors in natural populations.  The model system used in this experiment is the Gulf pipefish due to its reversal of sex roles concerning mating behavior.  Female competition over access to mates has led to secondary sexual characteristics that are used as visual signals by males to determine female quality.  Because these sexual traits appear to be estrogen regulated, the manipulation of perceived mate quality through exposure to a synthetic estrogen (EE2) can be achieved.  This study will therefore allow us to determine the effects of estrogenic exposure on mate recognition and offspring fitness. 

Partridge, C., Ahnesjö, I., Kvarnemo, C., Mobley, K., Berglund, A.,  and Jones, A.  Egg competition without cryptic gamete choice in a sex-role reversed pipefish.  Proceedings of the Royal Society of London B, in review.

Partridge, C., Shardo, J., and Boettcher, A.  Osmoregulatory role of the brood pouch in the euryhaline Gulf pipefish, Syngnathus scovelli.  Comparative Biochemistry and Physiology A, in review.

Ueda, N., Partridge, C., Bolland, J., Hemming, J., Sherman, T., and Boettcher, A.  2005.  Effects of environmental estrogens on male gulf pipefish, Syngnathus scovelli.  Bulletin of Environmental Contamination and Toxicology 74:1207 – 1212.

Partridge, C., Cazalas, C., Rozelle, J., Hemming, J., and Boettcher, A.  2003.  Small-Scale Captive Breeding of a Euryhaline Pipefish.  World Aquaculture September:51-54. 

Dupre, T., Granier, T., Keife, S., Marino, R., O’Rourke, S., Partridge, C., Schultz, D., Manhare, K., and Beck, J.  1999.  Variation of Mercury Concentration in Fish Taken from Lake Boeuf, Southeastern Louisiana.  Microchemical Journal 61:156-164. 

2006 Biology Department Student Travel Grant (Texas A&M).  Travel to Evolution 2006, Stony Brook, NY
2004 Environmental Protection Agency STAR Fellowship
2003 Excellent Teaching Assistant Award – Georgia Institute of Technology
2003 Best Student Presentation – Graduate Student Symposium at Georgia Institute of Technology