Three-way mating game of North American lizard found in distant Europea...(were not discovered in nature until 1996...)

"What's an incredible surprise is that it's so exactly the same, even right down to the same colors," he said. "That's kind of amazing because it says either the game has evolved twice or it's a game that's been played since the time of the dinosaurs, when the two species last shared an ancestor."

There are a few minor differences: in the American lizards the throats, not the bellies, are colored. The white-bellied form in Europe is matched by a blue-throated form in North America--although the two colors are similar in the ultraviolet spectrum, which lizards can see.

To investigate the social strategies of European common lizards, Sinervo and his colleagues spent five years studying lizards at five sites in the Pyrenees mountains of France. They captured more than 250 lizards per year, followed their successes and failures, and ran them on treadmills to gauge their physical prowess. The effect of the social system, they discovered, is a steady cycling of the prevalent color type in the population every four to eight years.

The cycle goes like this: one color type--orange, for example--is common in a patch of habitat for a year or two. During that time, the orange bullies spend their time attacking white-bellied lizards on nearby territories. The effort leaves females on their own territories unguarded, allowing yellow-bellied lizards to sneak in and sire offspring. So yellow males become prevalent for the next year or two. After that, white-bellied lizards proliferate as they team up to protect their mates from yellows' intrusions. But once the white-bellied males become numerous, they're easy pickings for the remaining orange-bellied males, who regain superior numbers as the cycle starts a
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