“True Blue Lizards” — The Discovery Files

In nature, putting the other guy first seems contradictory to an animal’s goals of survival and passing on its genes, so researchers have been trying to understand why the blue side-blotched lizard will step forward to battle an intruding aggressor, even though it could mean sacrificing its own chances to successfully mate. Now scientists have reported the first direct evidence that cooperative behavior in side-blotched male lizards arises from their genes. The findings, published in the May 9 Proceedings of the National Academy of Sciences by University of California–Santa Cruz’s Barry Sinervo and colleagues, represent some 20 years of research into the altruistic or “self-sacrificing” behavior.