Gills, growth and activity across fishes

Life history theory suggests that maximum size and growth evolve to maximize fitness. In contrast, the Gill Oxygen Limitation Theory (GOLT) in fishes other aquatic, water-breathing organisms is constrained by body mass-scaling of gill surface area. Here, we use new data a novel phylogenetic Bayesian multilevel modelling framework test this idea asking three questions posed GOLT regarding size, gills. Across fishes, ask whether area explains (1) variation von Bertalanffy coefficient (k) above beyond explained asymptomatic (W∞), (2) performance (a trait integrates tradeoff between k W∞) (3) more compared activity (as approximated caudal fin aspect ratio). Overall, find there only weak relationship among across species. Indeed, does not explain much (especially for those species reach same or performance. Activity five times Our results suggest factor growth, covariates (e.g. activity) are likely important understanding how life traits vary