Meeting Abstract
Far more species of organisms are found in the tropics than in the Earth’s temperate and polar regions, but the evolutionary and ecological causes of this pattern remain controversial. I explore the role that differential rates of speciation and extinction have played in generating large-scale gradients in the diversity of vertebrate animals in the oceans and on land. In the marine realm, tropical fish communities are much more diverse than coldwater communities found at higher latitudes, and a major class of explanations for this latitudinal diversity gradient proposes that warm reef environments serve as evolutionary “hotspots” for species formation. I assess relationship between latitude, species richness, and diversification rates across marine fishes, and I compare these patterns to those for several major groups of terrestrial vertebrates. I conclude by discussing ways in which the diversification-diversity relationship may vary across the Tree of Life.
