Linn and colleagues (2007) allowed members of male-female dyads of orb-weaving spiders to mate for either: (1) two natural copulations, (2) 2 hours, or (3) 48 hours (the natural mating period following the female's molt). 93% of group 1 females, 90% of group 2 females, and 28% of group 3 females mated with a second male when provided an opportunity to do so. The female's group membership did not influence the number of sperm found in the female's spermathecae. These results support
A) the hypothesis that prolonged mating reduces the chances that the female will be inseminated by another male.
B) the hypothesis that prolonged mating results in more of the male's sperm being transferred to the female.
C) both of the proposed functions of prolonged mating.
D) neither of the proposed functions of prolonged mating.

Question

Quizplus · Accepted Answer

The results indicate that prolonged mating (48 hours) significantly reduces the likelihood of females mating with a second male (28% compared to 93% and 90% in the other groups), supporting the hypothesis that prolonged mating reduces the chances of the female being inseminated by another male. The fact that the number of sperm in the female's spermathecae was not influenced by group membership suggests that prolonged mating does not necessarily result in more of the male's sperm being transferred, thus not supporting hypothesis B.

Linn and Colleagues (2007) Allowed Members of Male-Female Dyads of Orb-Weaving