A fatuous divorcé moves to a Celebration-like planned community in Florida, only to find it's infested with alligators. A nature buff plans to seduce his new girlfriend on a hiking trip, but leads her into a catastrophic blizzard. An aimless young drunk adopts a feral African wildcat to impress a pretty waitress. In Tooth and Claw, T.C. Boyle's fierce, funny new collection, men are fools, women hold the sexual cards, and nature is full of surprises, few of them pleasant. As always, Boyle writes wonderfully about oddballs, boozers, and the terminally self-deluded. But his best work here isn't satirical: In ''Chicxulub,'' he juxtaposes the history of civilization-ending asteroids with the account of a happy middle-aged couple, summoned in the night to a hospital with terrible news about their daughter. The impact is shattering.