Burmese pythons are voracious eaters. The mighty predators — which reach over 18 feet in length and 200 pounds (90.7 kg) in weight — can swallow prey as large as a deer. Researchers previously believed that the reptiles' massive heads and bodies allowed them to achieve this incredible feat. Now, a new study asserts it is the size of the python's "gape" — how wide it can open its mouth — that determines the size of animal it can swallow.