By Susan Milius
If you can’t look brilliant, forget halfway–decent looks. Go for total loser.
That fashion tip works—in male lazuli buntings—because their blue plumage shows signs of a rarely documented evolutionary pattern called disruptive selection, contend Erick Greene of the University of Montana in Missoula and his colleagues in the Oct. 26 Nature. Disruptive selection favors individuals with either of the opposite extremes of a trait and discourages moderation.