In a new study, fossilized droppings suggested that ancient ground squirrels ate the meat of much larger animals, including mammoths, bison and saber-toothed cats.

During courtship, male scissor-tailed nightjars crack their wings together to make a sharp snapping sound. It's the result of colliding arm bones.

The parasitic, flesh-eating fly has now been confirmed in cows, goats and dogs.