Hercules is a liger, a cross between a lion and a tiger. Weighing in at 900 pounds, he's the largest in the world. These mixes happen naturally at a nature preserve, according to experts, but not typically in the wild.

This liger has characteristics of both a lion and tiger. He has small ears like a tiger's, and a wide face with large cheek orbits, much like a lion.

A liger shows off massively sharp teeth to trainer Dr. Bhagavan "Doc" Antle, at a preserve in Myrtle Beach, S.C. Antle is the founder and director of T.I.G.E.R.S., The Institute of Greatly Endangered and Rare Species. Hercules eats about 100 pounds of meat a day.

A tiger smiles from behind a fence at Antle's reserve.

The zonkey is a cross between a zebra and a donkey. Boyd Biggs, who breeds and trains zonkeys outside of Fort Worth, Texas, says they are stronger, smarter and faster animals than traditional mules.

These striped legs belong to a zorse -- half zebra, half horse.

Kekaimalu, is the daughter of a false-killer whale and a bottlenose dolphin. The Sea Life Park in Hawaii is home to what they believe is the only known wholphin in the world.