Bronx Zoo cheetahs are attracted to Calvin Klein's "Obsession for Men," which scientists have tested to lure wild big cats close to camera traps. 

In a stunning display of amphibian machismo, tree frogs boogie before they brawl in this unprecedented video.

Fossils show that an ancient crocodile had mammal-like teeth and legs.

Scientists this year filmed deep-sea creatures for the first time at depths of more than 4,500 feet near Australia's coast, including the deep-dwelling sixgill shark biting on bait.

Built to rove for 90 days, Spirit has lasted six years on Mars. But now it's stuck and may lose power. Even standing still, though, Spirit can do a surprising amount of science, NASA says.

While battling a blaze on the slopes of Mauna Kea