Just a few thousand years ago, humans followed monsoon rains to the Sahara Desert and were greeted with lush vegetation and plentiful wildlife.
The most feared creatures at the top of a food chain maintain equilibrium, but humans often disturb this delicate balance.
The fossil record is chock full of big beasts that didn't make it. Find out why, and what lessons can be learned.
Although many of Earth's largest animals are endangered, it's not too late to take steps to prevent their demise.
Active teaching seems to be rare in the animal world. Perhaps painful stings make for attentive students.
Scientists suggest a midlife crisis killed off many of these beasts just as they entered their sexual prime.
A 6,000-year-old corridor between Yellowstone and Grand Teton national parks shrinks as developments move in.
One stiff drink makes people fail to notice a person in a gorilla suit running across the TV screen.
By putting some ants on stilts and lopping the legs off others, researchers conclude an internal pedometer is at work.
Nature's own reality show is getting such high ratings that officials ask viewers to limit their time.
Among the discoveries: new species of frog, mammals that cry like babies, and 11 species found only in the Rubeho region.
By spying on their neighbors, client fish enlist the aid of the most trustworthy skin-cleaning fish.
For the second year running, Phoenix takes the top place, where residents sweat enough to fill an Olympic-sized swimming pool every three hours.
Once thought to be produced by the liver, scientists have tracked the key antifreeze protein to the fish's pancreas.