Meeting Abstract
When sexual signals are perceived during growth and development they can provide information regarding the social conditions likely to be encountered as an adult. Perception of cues related to the presence and density of future mates and competitors can trigger plastic developmental mechanisms which result in adaptive phenotypes. Previous studies have shown that adult male Teleogryllus oceanicus field crickets from the island of Kauai, Hawaii reared alone and without hearing conspecific song are both strongly phonotactic, engaging in satellite behaviors when they hear a calling male, as well as reducing investment in body size and immunity. Such behavioral and physiological plasticity in response to the acoustic environment is particularly relevant for this particular population of T. oceanicus because a wing mutation has recently evolved there that renders >90% of males incapable of singing. Here we examined whether another source of population density information, i.e., the presence of other males, affects behavior, size, and immunity. Specifically, we examined satellite behavior, body condition residuals, and immune response by males reared singly and in groups in the presence or absence of conspecific song. Immune response did not vary with acoustic environment or rearing density; we therefore found no evidence for density-dependent prophylaxis. We did find, however, that males reared without song were significantly more phonotactic than those reared with song regardless of whether other individuals were present during their development or not. This finding suggests that song may be a special signal during development conferring information about adult mating competition, and that male crickets on the island of Kauai are likely engaging in adaptive satellite behavior regardless of population density.
