Is the medium the message? Functional diversity across abiotic gradients in freshwater electric fish
This article was originally published here
Incorporates Comp Biol. March 28, 2022: icac010. doi: 10.1093/icb/icac010. Online ahead of print.
Evolutionary transitions across abiotic gradients can occur among habitats at multiple spatial scales, and among taxa and biota across a range of ecological and evolutionary timeframes. Two diverse groups of electric fishes, the Neotropical Gymnotiformes and the Afrotropical Mormyroidea, offer interesting examples of potentially convergent evolution in aspects of morphological, physiological, and life-history traits. We examined the biogeographic, morphological, and functional patterns of these two groups to assess the degree of convergence in association with abiotic environmental variables. Although there are superficial similarities between groups and continents, we found many more differences in habitat occupancy, electrical signal diversity, and morphological disparity. These differences likely correlate to differences in biogeographic histories between the Neotropics and Afrotropics, biotic factors associated with aquatic life and electrical signals, and sampling issues that plague both groups. Further research and sampling is needed to make further inferences about how electric fish move through various freshwater habitats across the microevolutionary and macroevolutionary scales. We find little evidence that abiotic gradients in the freshwater habitat milieu have driven convergent evolution of functional traits in these two continental radiations of electric fishes.