To most people, two-headed snakes are only heard about in medieval stories, but the truth is that two-headed snakes do exist and quite a handful of them have been found over recent years. One of the most famous examples is Russell's viper snake which has been found in India in 2020. The specimen is very interesting as despite being connected to a single body, each head has its own ideas and tactics on how to catch prey or evade predators, making it vulnerable in the wild.
Experts from the University of Michigan have argued that Russell's viper is "one of the most dangerous snakes on the planet" and this exact specimen is twice as deadly because with two heads it can deliver a double dose of venom.
Another more recent specimen of another species known as the southern brown egg-eater snake has been found with two heads in South Africa. This species is harmless, which makes it even rarer to find as it is hunted down by the many predators found in Southern Africa.
The recent findings show that two-headed snakes are not rare, but what makes them rare is their inability to be efficient in the wild in order to protect themselves. Nick Evans, the snake rescuer who caught this exact specimen mentioned in an interview that having two heads slows down the snake, as two brains are trying to command one body.
"Sometimes, the heads would try to go in opposite directions from one another, other times, it would rest one head on the other. That seemed the most effective way of moving.” (Quote by Nick Evans)
In other cases where scientists have observed the behavior of snakes with two heads, they have observed that with time one head becomes more dominant and the other head just simply tags along, listening to the orders given to the body by the dominant head.
An article from the Guardian mentioned that a two-headed snake has the chance to be born in around one in 100,000 births.
"Two-headed animals are considered in many cultures to be a portent of disaster, and they have frequently appeared in mythology. But although they are rare, happening in around one in 100,000 live births in the wild, two-headed snakes do turn up fairly frequently." (Quote by Martin Belam)
Taking into consideration that there are millions of snakes from different species born every year around the world, it makes the occurrence of two-headed snakes not so rare after all. This condition is commonly known as polycephaly which occurs in the same way conjoined twins are formed. An embryo that has begun to split into identical twins stops before fully dividing.
It is interesting however that we do not see other types of animals born with two heads. There has been a recent discovery of lizards with two heads, but they are quite close to snakes.
We do not tend to see other wild animals with two heads and this is most probably because of the two-head symptom that makes two-headed snakes so vulnerable in the wild. Having two heads that keep butting over the control of the body consists in being ineffective predators and very vulnerable prey.