P2.156 Thursday, Jan. 5 The relative contributions of allometry, individual behavior, and group dynamics to reproductive success in the bluebanded goby (Lythrypnus dalli) SOLOMON-LANE, TK*; PRADHAN, DS; WILLIS, MC; GROBER, MS; Georgia State Univ., Atlanta; Georgia State Univ., Atlanta; Georgia State Univ., Atlanta; Georgia State Univ., Atlanta firstname.lastname@example.org
Although the fitness benefits of sociality are undisputed, it remains unclear how individual social behavior contributes to emergent group dynamics and subsequent individual / group fitness optimization. To test whether certain classes of social behavior and/or group dynamics maximize reproductive success, we quantified egg production and recorded agonistic, affiliative, and reproductive behavior in stable social groups of bluebanded gobies (Lythrypnus dalli), a highly social, marine fish that forms harems of a dominant male and multiple subordinate females. The male fertilizes and cares for eggs contributed by each female in the group. As males increase their fitness by increasing the reproductive success of their females, two factors, in combination, determine reproductive output: 1) the number of eggs laid and 2) the percentage of those eggs that males fertilize, keep healthy, and protect from predation (e.g., females). Single behaviors or traits, such as female size, male courtship, or male approach or displacement rates, do not explain the variation in fitness, eggs laid, or male egg retention. In contrast, males with high agonistic efficiency, the percent of approaches that result in displacement, have higher egg retention. Agonistic efficiency, however, is neither necessary nor sufficient for high fitness. Rather, it is an example of a broader class of socially apt behaviors that are associated with certain emergent properties of social group interactions. This work explores the fitness consequences of these behavioral phenotypes.