New paper in Science on how metabolic asymmetry shapes the global diversity of marine predators
Generally, biodiversity is higher in the tropics than at the poles. This pattern is present across taxa as diverse as plants and insects. Marine mammals and birds buck this trend, however, with more species and more individuals occurring at the poles than at the equator. We ask why this is (see the Perspective by Pyenson). We analyzed a comprehensive dataset of nearly 1000 species of shark, fish, reptiles, mammals, and birds. We found that predation on ectothermic (“cold-blooded”) prey is easier where waters are colder, which generates a larger resource base for large endothermic (“warm-blooded”) predators in polar regions.