LAUSR

Significance Whole genome duplications have played an important role in animal evolution, often preceding major radiations and adaptive novelties. Despite this, animals with multiple genome copies (called polyploids) are rare. To understand what factors contribute to the formation and survival of polyploid animals, I analyzed a biogeographical dataset in three animal groups: amphibians, ray-finned fishes, and insects. Each group exhibited a latitudinal gradient, with polyploid species more likely to occur at higher latitudes. This gradient appears to be largely driven by climate cycles, with polyploid species more likely to inhabit areas that have recently experienced deglaciation or severe temperature changes. This result demonstrates how polyploidy is correlated with newer, more extreme environments and may indicate genome duplication’s role in facilitating adaptation.