The evolution of autotomy in leaf-footed bugs

Sacrificing body parts is one of many behaviors that animals use to escape predation. This trait, termed autotomy, is classically associated with lizards. However, several other taxa also autotomize, and this trait has independently evolved multiple times throughout Animalia. Despite having multiple origins and being an iconic anti-predatory trait, much remains unknown about the evolution of autotomy. Here, we combine morphological, behavioral, and genomic data to investigate the evolution of autotomy within leaf-footed bugs and allies (Insecta: Hemiptera: Coreidae + Alydidae). We found that the ancestor of leaf-footed bugs autotomized and did so slowly; rapid autotomy (< 2 min) then arose multiple times. The ancestor likely used slow autotomy to reduce the cost of injury or to escape non-predatory entrapment but could not use autotomy to escape predation. This result suggests that autotomy to escape predation is a co-opted benefit (i.e., exaptation), revealing one way that sacrifici...