Polycephaly is the condition of having more than one head. The term is derived from the Greek . The most commonly observed two-headed animals are turtles and snakes. Other species with known two-headed occurrences include cattle.
The two-headed monsters of myth may have a basis in reality. Two-headed snakes are rare but not unheard of, and one recently found in Spain.
It's said that each of us is his or her own worst enemy. That's especially true when you're a hungry, venomous snake with two heads. One such.