The dorso-ventral righting reflex of purple shore crabs is impeded by sexually selected claws but not by leg autotomy

Abstract

ABSTRACTLocomotion has been a well-studied avenue for questions regarding the costs of autotomy. However, previous studies have focused on traditional means of locomotion such as walking, running, or swimming; an unexplored aspect of locomotion as it relates to the costs of autotomy is the dorso-ventral righting reflex, or DVRR. Using a comprehensive set of treatment groups, we explored how autotomy affects the DVRR in the crab Hemigrapsus nudus. Our results suggested that missing walking legs had no impact on an animal’s ability to complete the DVRR. However, the enlarged claws of males were shown to impede the speed at which males can right themselves out of the compromising, supine position. This is a novel example of how a sexually selected trait can negatively affect animal locomotion.