Leg Regeneration Trade-Offs in the Twostriped Walkingstick (Phasmatodea: Pseudophasmatidae)

AbstractAppendage regeneration is a unique tool to study resource allocation trade-offs; the resources allocated to grow an appendage a second time can come at the expense of other structures. We studied the effects of both front and hind leg regeneration on a suite of traits in Anisomorpha buprestoides (Stoll) (Phasmatodea: Pseudophasmatidae), the twostriped walkingstick. This species is ideal for resource allocation questions because it has a relatively long life history as well as a large group of traits to measure for any potential trade-offs (including large defensive glands in the thorax that are used to deter predators). For females, there were no apparent trade-offs with respect to antennae, eyes, defensive glands, nonregenerated legs, cerci, genital plates, and/or body size. In males, there were no also no apparent trade-offs with respect to antennae, eyes, defensive glands, nonregenerated legs, cerci, or testes, but males that regenerated a leg were larger (but not heavier) than nonregenerating males. Future work at the physiological level will hopefully elucidate the nature of acquisitionallocation trade-offs in phasmids, and how such trade-offs may have shaped their evolution.