A new study indicates that early North Americans could have over-hunted wild horses into extinction.
A hormone boost from mom makes cubs more aggressive, increasing their chances of survival. But the benefit comes with a huge cost when it comes time to mate and conceive.
Why screaming line drives are tough to catch, curveballs are hard to hit, and rising fastballs are mere illusions.
Walrus moms abandon pups in open water in unprecedented numbers. The pups presumably died, but not before researchers heard their cries.
The emergence of flowering plants 100 million years ago may have led to the explosion in ant diversity that occurred around the same time, scientists say.
Donâ€™t throw away those bifocals just yet, but these spectacles changes prescriptions with the flick of a switch.
The finding violates theories and could change how scientists think about liquid chemical reactions.
There used to be 150 glaciers in Montana's Glacier National Park. Now there are 26. A good-bye tribute, in pictures.