Meeting Abstract
Autotomy, self-controlled limb loss, is an extreme trait observed throughout the animal kingdom; lizards can drop their tails, crabs can drop their claws, and crickets can release their legs. These repeated evolutionary origins suggest that autotomy is adaptive. Yet, it remains unclear what selective pressures promote and maintain this extreme trait. While multiple adaptive hypotheses exist, research has generally focused on autotomy’s adaptive value as a form of predator escape. However, autotomy could also be selected to reduce the cost of an injured limb. Previously, this alternative hypothesis has been challenging to directly test because when an injury occurs on an autotomizable limb that limb is almost always dropped. However, we have recently identified a species, Narnia femorata (Insecta: Hemiptera: Coreidae), where some individuals autotomize limbs in response to injury, but some do not. This natural variation allowed us to investigate both the survival costs of retaining an injured limb and the benefits of autotomizing it. In this study, we find a positive association between autotomizing injured limbs and survival, providing evidence of a new, and likely widespread, benefit of autotomy — reducing the cost of injury.
