Abstract
Understanding the importance of intraspecific phenotypic differentiation among wide ranging populations remains at the core of life history research. Phenotypic variation in life history traits such as offspring size, growth, and survivorship are the target of studies attempting to understand the coevolution of these traits. Species with a wide geographic range have long been used for these studies because adaptation to local environmental conditions is expected. We collected diamondback terrapin, Malaclemys terrapin, eggs from multiple sights within its range to quantify variation in egg size and the amount of stored energy reserves provided within the eggs. Females in southern populations produce significantly larger eggs than females in northern populations. The larger eggs contain a larger yolk and have higher lipid stores. Eggs from three populations were incubated at three temperatures to compare the thermal influence of lipid utilization and development rates among the populations. The variation in incubation period was explained by the incubation temperature and the source population. We will present preliminary results on hatchling energetics and metabolic rates resulting from different incubation temperatures.