Meeting Abstract
Quantitatively linking morphology with performance at one developmental stage is important because it allows us to better understand the functional, ecological, and evolutionary implications of morphological diversity. Links between morphology and performance may also be age dependent as the architecture needed for optimal performance may be underdeveloped in young animals. Few studies have examined how the relationship between form and function changes across ontogeny. Here, we assess this link in the amphibious, simultaneously hermaphroditic mangrove rivulus (Kryptolebias marmoratus) fish. This species is capable of transporting itself over terrestrial landscapes to new aquatic habitats using a behavior known as tail-flip jumping. Using tactile stimulation during timed trials and a clearing and staining procedure, we assess jumping performance and variance in caudal bone dimensions. We test the hypotheses that: i) morphology and jumping performance vary as a function of age; ii) jumping performance increases significantly with age, independent of size; and iii) phenotypic variance and covariance among morphological and performance traits change across ontogeny. We focus on describing variance in bones within the caudal peduncle (i.e. parahypural, epural, and hypurals) because this region is intimately involved in terrestrial jumping. In support of our hypotheses, we found a significant increase in size-adjusted jumping performance with age, and modification to the correlation structure among traits across ontogeny. The significant link between form and function found at prematurity, however, disappeared at later stages in ontogeny. This implies that different functional mechanisms may be associated with high jumping performance at different stages in development.
