Evolution and drivers of long-distance vocal communication in mammals

Abstract Long distance communication is important for life history processes in many species. Long-standing debate exists about the type of evolutionary history and environmental drivers which have shaped the propagation of animal sounds. We compare the maximal propagation distance of calls for 103 mammalian species using comparative analysis. While maximal propagation distances in aquatic mammals are best explained by body mass, in terrestrial mammals the effects of home range, with call type, habitat, and sociality best explain maximal propagation distances. The difference between effects of body mass and home range on maximal propagation distances of mammal sound signals suggests that sound propagation strongly depends on environmental pressures and evolutionary mechanisms, within physical laws. Evidence is provided that the acoustic adaptation hypothesis may be more associated with home range than body mass in terrestrial mammals, while predation may be an important component that facilitates this adaptation for mammals in different environments. Understanding these evolutionary trait drivers provides one key step to answer whether vocal species could be affected by environmental and anthropogenic acoustic pressures, and whether they can evolve in response to those pressures.