Kin Recognition in two Species of Cellar Spiders, (Pholcidae), and its Effects on Inter- and Intra-Specific Predation of Spiderlings

摘要

Intraguild predation and cannibalism are important behaviors that provide resources and influence interactions between different predators. Cannibalistic specks should have a mechanism to identify offspring and suppress predation. We tested this hypothesis using two nonnative species of pholcid spiders in Ohio, Pholcus phalangioides and Pholcus manueli. In the laboratory we allowed females of both species to produce clutches. Once hatched the spiderlings were separated from their mother for 1 h and then reintroduced to the mother, a conspecific, or were introduced to an heterospecific adult female. The proportion of prey items consumed was recorded. Pholcus phalangioides predation patterns were consistent across species, but P. manueli feed on P. phalangioides young at twice the rate of young conspecifics, treating heterospecific young similar to control crickets. Further, mothers did not prey on their own young. These results highlight an important biological difference between the two species and indicate that intraguild predation may play an important role in interactions between the two species.