The Amazing Sinervo & his Enlightening Lizards, Episode 2: Black Hats vs. White Hats

In the journals this week Barry Sinervo reports the existence of a gene for cooperative behavior in lizards, which at the same time flags a lizard as "a good guy." It does this with blotches of color on either side of a lizard's throat. Such a gene is just the ticket to avoiding exploitation even while acting helpful, because you can tell exactly who else in the community is a team player. Otherwise, helpful behavior and "playing nice" might never have evolved.

Previously, Sinervo and others in his lab showed rock-paper-sciccors cycles of competition by lizard color morphs, showing that no one lizard color was "the fittest" for its habitat and that no constant "niche" for color existed. So you don't get species diversity just from how many different things there are to hunt or scavenge, it appears. Biodiversity can arise just from the dynamics. (Someone spotted diversity dynamics in guppies just this week.)

Bow to Sinervo, Lizard King.