Solo spiders live longer than groupies

RIVERSIDE, Calif., Oct. 7 (UPI) -- When lighting out for new territory, some spiders prefer to go it alone. New research suggests the pioneer spirit pays off.

According to a new study published in the journal Animal Behaviour, loner spiders live longer than those that travel in groups. Scientists at University of California, Riverside say group dynamics explains the disparity.

"This is a pretty surprising result that breaks from long-held intuitions that moving as a group would enhance survival rates [for social organisms]," Jessica Purcell, an assistant professor of entomology, said in a news release.

As previous research has shown, sustainable group dynamics in spider colonies rely on the right balance of aggressiveness and passivity. In recent experiments, groups of spiders placed in foreign environs with new colonies failed to survive.

Researchers hypothesize that because of colonies' preference for the right mix of personality traits, foreign groups have a nearly impossible task of assimilating.

Experiments showed that solitary spiders on the other hand, whether passive or aggressive in disposition, successfully incorporated themselves into foreign colonies and were also able to survive on the own.

Of the more than 40,000 spider species in the Americas, only 30 are known to organize socially.

Researchers believe the inability of migrating groups to integrate into foreign colonies may explain how spider speciation happens. In an odd way, the exclusivity of foreign colonies encourages diversity.