For a male wolf spider, approaching the wrong female with a romantic overture can be deadly: lady wolf spiders often cannibalize males that they don't want to mate with. Findings published online this week by the Proceedings of the National Academy of Sciences USA indicate that females of this species develop preferences for certain males based on early social interactions, a trait that is virtually nonexistent among invertebrates.
Among spiders, the wolf spider, Schizocosa uetzi, is unique because males can take on a variety of different looks, or phenotypes. Some have ornamental tufts of hair on their forelegs, and the exoskeleton comes in a variety of colors. Eileen Hebets of Cornell University introduced 81 sexually immature female wolf spiders to a variety of sexually mature males in the laboratory. Once the females were sexually mature and ready to take on a mate, Hebets again exposed them to a variety of male spiders. She found that females most often chose a mate of a familiar phenotype. In addition, those that had previously met more than one type of male were more likely to devour a suitor that was completely unfamiliar to them.
"Social experience influences mate choice," Hebets explains. "This shows that invertebrates have social recognition, and it can be maintained and remembered even through the molting process. These influences affect adult behavior and possibly the evolution of traits."