Meeting Abstract
Across taxa, parents have major effects on their offspring by influencing the early developmental environment. In birds, one of the most important aspects of the developmental environment is egg incubation. Small changes (<1°C) in average incubation temperature have large effects on offspring post-hatch phenotypes. Further, it has recently been shown that average incubation temperatures differ among eggs within the same nest, to the extent (i.e., >1°C) to which differences in offspring phenotypes should result. A potential, yet unstudied, consequence of within-nest incubation temperature variation is inequality in competitive ability among individuals in the same brood. This could alter early social dynamics, and thus further affect offspring phenotypes. To investigate if incubation temperature affects competitive behavior, we incubated wood duck (Aix sponsa) eggs randomly at either 35 or 36°C and formed mixed-incubation temperature broods of similar-age ducklings once hatched. We conducted four behavioral trials to determine duckling competitive ability for heat and food. Contrary to our predictions, we found no effect of incubation temperature on duckling competitive behavior. However, we found that ducklings incubated at the higher temperature had larger body sizes than those incubated at the lower temperature throughout the study. Thus, our results suggest that individuals incubated at low temperatures are at a physiological deficit, but this is not exacerbated by decreased competitive ability.
