As a defense strategy, many crustaceans perform one of two well described stereotyped single fast tailflips (~6 ms in adult crayfish), which are triggered by a neural circuit that includes medial giant interneurons (MG) and lateral giant interneurons (LG). Tailflips can also occur without these giant interneurons firing, however; these non-giant tailflips are variable, repetitive, and significantly longer (~150 ms). Previous work showed that crayfish exposed to natural stimulus respond with a non-giant tailflip significantly faster than when presented with an artificial stimulus and that complete removal of claws lowered tailflipping threshold. We tested whether compromising weapons would influence tailflipping. Claws were deafferented by cutting the leg nerve between the coxa-basis joint. Crayfish were presented with artificial tactile stimuli, and their tailflipping behaviour was video recorded in three conditions: intact, deafferentation of one claw, and deafferentation of both claws. Crayfish with either one or both claws deafferented tailflipped greater distances than intact animals when tapped. The orientation that crayfish assumed after tailflipping was not significantly different with claw deafferentation, however. We plan to conduct similar experiments compromising vision and in species that have no claws and use alternate weapons (e.g., antennae).
Espinoza, Sandra Y. and Faulkes, Zen, "Compromised weaponry enhances crayfish tailflipping" (2007). Biology Faculty Publications and Presentations. 38.
Integrative and Comparative Biology