Meeting 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 limbs when threatened, and through subsequent molts, regenerate the lost limb. Autotomizing a limb is therefore costly not only in terms of loss of function, but also in terms of limb re-growth; failing to autotomize a limb, however, could be deadly. Here we examine variation in latency to autotomize the snapper claw in Alpheus angulosus. We measured latency to autotomy of mature snapper claws in a large cohort of shrimp (nf=36, nm=36). After initial snapper autotomy, we also measured latency to autotomize the regenerating claw based on molt stage. We found autotomy to be based on threat type rather than duration among all shrimp, as a distinct pattern in latency to autotomize appeared in our data. We also found significantly longer latency to autotomize in males, suggesting a greater cost of snapper autotomy to males than females. Surprisingly, amount of investment in claw regrowth (as measured by molt stage) did not affect latency to autotomize. Regarding post-autotomy claw transformation, we have found that plunger/socket formation occurs rapidly, restoring snap behavior after the first molt, despite reduced claw size. Our analysis of sensory plasticity exhibits appearance and proliferation of a new setae type by molt two of transformation, suggesting that sensory setae follow behind snapping functionality and may be less important for shrimp fitness. Through these perspectives, we will present the evolutionary tradeoffs of autotomy and plasticity in the snapping shrimp.
