Meeting Abstract
Mangrove rivulus (Kryptolebias marmoratus) is a self-fertilizing hermaphroditic fish, giving rise to progeny that are isogenic clones of the parent generation. Found in mangrove swamps from central Florida, USA, to southern Brazil, these amphibious fish make occasional bouts onto land using the tail-flip to locomote when out of the water. Most often housed in the lab in small containers without the ability to access non-aquatic environments, we predicted that individuals from different populations, both genetically distinct and geographically distant, would decline in jumping performance when in captive conditions. We collected specimens in the field from three genetically different populations in the Florida Keys, USA (n = 5 individuals per population), and three populations from Lighthouse Reef Atoll, Belize (n = 12 individuals per population). All Florida individuals underwent an exercise assay once per month for a 13 month period. Six individuals from each Belize population underwent exercise assays for all 13 months, with the remaining individuals acting as a control, undergoing the exercise assay for only the first and final months to determine the effects of periodic exercise vs. no exercise on jumping performance. Individuals were placed in a shallow, empty wading pool covered with wetted bench liner paper with a camera (60 fps) suspended above the arena to record all behaviors. Fish were able to voluntarily move for two minutes, immediately followed by 30 seconds of being chased in the arena to elicit maximum jumping performance. Latency to first movement and jump performance changed through time for both geographically distant and genetically distinct populations, suggesting that captivity and genetic differences interact to produce changes in jumping performance.
