Gw. Uetz et al., LIMB REGENERATION AND SUBSEQUENT ASYMMETRY IN A MALE SECONDARY SEXUALCHARACTER INFLUENCES SEXUAL SELECTION IN WOLF SPIDERS, Behavioral ecology and sociobiology, 38(4), 1996, pp. 253-257
Males of the brush-legged wolf spider Schizocosa ocreata (Hentz) have
conspicuously decorated forelegs used in courtship and agonistic displ
ays. Approximately one in five juvenile males has a missing or regener
ating foreleg, and regeneration of a leg lost during development usual
ly results in the absence of a decorative tuft on that leg. The subseq
uent asymmetry in this male secondary character significantly decrease
s success in both courtship of females and male-male agonistic interac
tions. Experimental removal of tufts from one leg of previously succes
sful symmetric males produces similar results. As a test for concomita
nt behavioral effects, female spiders were shown video images of a cou
rting male with symmetric tufts and the same video image altered to ha
ve asymmetric tufts. Female receptivity to the asymmetric video image
was lower. In contrast to fluctuating asymmetry resulting from develop
mental instability, leg tuft asymmetry in S. ocreata most likely arise
s from a single event during ontogeny - possibly leg loss from an aggr
essive or predator encounter and may serve as a quality indicator in f
emale mate choice.