Meeting Abstract

85.1  Tuesday, Jan. 6  Heritability and genetic correlation of call duration and condition in gray treefrogs: a test of genic-capture WELCH, A.M.*; SMITH, M.J.; GERHARDT, H.C.; College of Charleston, SC; Arthur Rylah Institute, Victoria, AU; Univ. of Missouri, Columbia welcha@cofc.edu

Genetic variation in male sexual displays is a key ingredient in sexual selection, fueling the evolution of more attractive displays, allowing choosy females to gain the benefit of attractive sons, and facilitating correlated evolution of female preference and male display. What prevents sexual selection from quickly eroding genetic variation in display attractiveness? The genic-capture model suggests that this variation persists because condition-dependence of display traits translates genetic variation in condition into genetic variation in the display. We tested this model in gray treefrogs (Hyla versicolor). Male gray treefrogs produce energetically expensive advertisement calls, and females prefer long-duration calls. To test the predictions of genic-capture, we assessed genetic variance in call duration and in body condition, as well as genetic covariance between condition and call duration. Offspring from artificial fertilizations were raised to maturity in the laboratory, body condition was measured at several points during development, and calls of male offspring were recorded in a controlled acoustic environment. We find significant heritability in both body condition and call duration, but no significant genetic correlation between the two. Heritability of call duration demonstrates the potential for this trait to evolve in response to sexual selection. In addition, females mating with males that produce longer calls are expected to benefit via enhanced sexual attractiveness of their male offspring. However, a lack of genetic correlation between call duration and condition suggests that the ample genetic variation in call duration is likely maintained by some mechanism other than genic capture.