Autotomization and Recovery in the Snapping Shrimp, <i>Alpheus angulosus<i>
Loading...
Date
Authors
Cooney, Patricia
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The snapping shrimp (Alpheus spp.) exhibit extreme claw lateralization, presenting a large snapper and a small pincer, which are used for different behaviors. Like most crustaceans, the snapping shrimp is able to autotomize, or drop, limbs when threatened, and through subsequent molts, regenerate the lost limb. Though autotomy is costly in terms of loss of function and limb re-growth, failing to autotomize a limb could be deadly. In this study, we document the breakage plane of A. angulosus and examine variation in “drop latency”, or the latency to autotomize the snapper claw in response to a standardized physical threat. We measured drop latency of mature snapper claws in a large cohort of shrimp (n=96). We found autotomy to be responsive to threat type rather than threat duration among all shrimp. Specifically, autotomy occurrences were distributed in clusters around threat intensity changes, rather than normally distributed throughout threat time. We also found significantly longer drop latency in males than females, suggesting a greater cost of mature snapper autotomy to males (p=0.004). After initial snapper autotomy, we also measured latency to autotomize the regenerating claw based on molt stage. Surprisingly, transforming molt stages exhibited significantly shorter average drop latency than mature snapper autotomy (p=0.008). The breakage plane in this species differs from that of related organisms, suggesting interesting implications for phylogenetic divisions in crustacean anatomy. Our assessment of mature snapper and transforming claw autotomy behaviors provides insight into the costs of autotomy and the differing values of these claws throughout individuals’ lives. Through these perspectives, we present the evolutionary costs of autotomy and transformation in the snapping shrimp.
Description
Keywords
Snapping shrimp, Alpheus angulosus, Autotomy, Claw Transformation