A Selfish Link

 FROM RICE UNIVERSITY...

One of nature's most prolific cannibals could be hiding in your pantry, and biologists have used it to show how social structure affects the evolution of selfish behavior.

Researchers revealed that less selfish behavior evolved under living conditions that forced individuals to interact more frequently with siblings. While the finding was verified with insect experiments, Rice University biologist Volker Rudolf said the evolutionary principle could be applied to study any species, including humans.

In a study published online this week in Ecology Letters, Rudolf, longtime collaborator Mike Boots of the University of California, Berkeley, and colleagues showed they could drive the evolution of cannibalism in Indian meal moth caterpillars with simple changes to their habitats.

Also known as weevil moths and pantry moths, Indian meal moths are common pantry pests that lay eggs in cereals, flour and other packaged foods. As larvae, they're vegetarian caterpillars with one exception: They sometimes eat one another, including their own broodmates.

In laboratory tests, researchers showed they could predictably increase or decrease rates of cannibalism in Indian meal moths by decreasing how far individuals could roam from one another, and thus increasing the likelihood of "local" interactions between sibling larvae. In habitats where caterpillars were forced to interact more often with siblings, less selfish behavior evolved within 10 generations.

Rudolf, a professor of biosciences at Rice, said increased local interactions stack the deck against the evolution of selfish behaviors like cannibalism.  READ MORE