P2.32 Thursday, Jan. 5 More of a good thing: The positive relationship between vertebral number and performance ACKERLY, K. L.*; WARD, A. B.; Adelphi University; Adelphi University firstname.lastname@example.org
Environmental conditions significantly affect the development, morphology, and performance of aquatic vertebrates, as shown by previous research in diverse groups of aquatic vertebrates, including fishes and amphibians. Studies have shown that temperature during development affects vertebral morphology, such that individuals reared at higher temperatures tend to develop a lower number of vertebrae than individuals reared at lower temperatures. Studies have also displayed the impact of vertebral morphology on performance. In order to demonstrate the relationship between environmental conditions and performance through morphology, we investigated the relationship between the effect of temperature on vertebral development, and the subsequent effect of any discrepancy on burst swimming performance in two model aquatic vertebrates, zebrafish (Danio rerio) and axolotls (Ambystoma mexicanum). Embryos of both species were collected and evenly distributed among a range of species appropriate temperatures prior to the onset of somitogenesis. Following development, startle responses were recorded and individuals were analyzed for either vertebral number or muscle fiber composition. Our results indicate that small fluctuations in temperature can significantly influence an individual’s vertebral development, which can then subsequently impact survival. We found that individuals reared in higher temperatures develop a lower number of total vertebrae and a less favorable ratio of pre-caudal to caudal vertebrae for maximum performance. As a result of these morphological discrepancies, these individuals were found to have decreased burst swimming performance, as they achieved significantly less velocity and a slower overall response time. Placing these results in the context of a changing climate, these results indicate the significant impacts of rising temperatures on aquatic vertebrates.