Meeting Abstract

P2.136  Tuesday, Jan. 5  Sperm competition and mate order effects in red-sided garter snakes FRIESEN, Chris/R.*; MASON, Robert/T.; Oregon State University friesenc@science.oregonstate.edu

Female promiscuity creates the potential for high variance in male mating success and thus sexual selection due to postcopulatory processes. In addition, the dynamics of a mating system can be strongly affected by female promiscuity—i.e., when and if a female remates. In the mating system of the red-sided garter snakes of Manitoba, Canada, female choice seems to be extremely limited in large courtship aggregations within the den, where male mating success is random with respect to his size. Once mating occurs in the den, females may then remate in less dense aggregations away from the den to ensure that a large (fit) male will sire at least some of her offspring. This hypothesis requires that second-male precedence prevails. We tested this hypothesis using controlled matings where after a female mated with one male we mated her with a second male. We report the results of paternity analysis, and correlates of male paternity success. No other study has investigated the combined effects of mate order, copulation duration, and male size as correlates with paternity success in any species of snake. Further, one curious result is suggestive of potential female control over paternity.