Toward an integrated understanding of animal weapons

Abstract Animals resolve conflict using an astonishing array of weapons—from electric fields and sonic shock waves to deadly venom and high-impact strikes. Yet, most weapon research has been narrowly focused, for example, only considering mechanical weapons under sexual selection. Furthermore, few studies have examined how weapons are integrated into animal phenotypes. For these reasons, it is not surprising that major questions remain about why weapons have evolved such extraordinary diversity in form and function. By synthesizing insights across weapon modalities and research traditions, we identify key themes for future research on animal weapons and discuss several ways in which research into animal weapons can provide broad insights into evolutionary processes.