Meeting Abstract

P3.125  Friday, Jan. 6  Allometry of sex allocation for a simultaneous hermaphrodite: a contrast of patterns at high and low densities HART, Mary K; University of Kentucky mkhart0@yahoo.com

Recent studies have demonstrated that sex allocation patterns among populations and social groups vary continuously with differences in density and sperm competition. That is, greater density is positively correlated with sperm-competitive behavior and proportional male allocation in a simultaneous hermaphrodite, both within and among populations. In addition, proportional sex allocation is determined through a combination of reproductive investments in ovarian and testicular gonadal tissue relative to body size. In the present study, I examine whether the patterns of allometry associated with measures of sex allocation (proportional male allocation) are consistent over time for populations at high and low density. Populations of Serranus tortugarum in the Bocas del Toro, Panama region have been repeatedly sub-sampled across the representative size range from 2004-2007. These yearly sub-samples (n = 50-150 individuals each) can be divided based on high (N=6) and low reef densities (N=7). This study compiles a large dataset of allometric patterns in reproductive investments with size from individuals of a representative size range for the population. I predict that for the low density populations, I will see a consistently greater investment in ovarian tissue with size and for high density populations, I will see a consistently greater investment in testicular tissue with size.