Entering its 17th year, an extremely unusual two-headed snake has surprised its keepers and defied all odds of its impending doom.

The rat snake, which are actually snakes that share a slithering body, have grown up to five feet in length and have already exceeded the life expectancy of their regular counterparts in the wild.

The rare snake was found floating in her backyard in the small town of Delta, Missouri, in 2005 and brought to the Cape Girardeau Nature Conservation Center.

The existence of a two-headed snake was already a remote chance in 100,000, and the fact that it reached such a mature age made it a wonder in a hundred million, according to the snake expert. Steʋe Allain, member of the council of the British Herpetological Society.

He said: ‘I know of another two-headed snake that survived to be 20 years old, so it is not possible that it survived that long.

However, it is extremamente unproƄaƄle. I would say that it is likely to be one in a hundred million.

This extremely rare two-headed snake, found in a Missouri backyard in 2005, has managed to outlive its seventeenth year.

The rat snake, which is actually two rat snakes sharing a slithering body, has grown to five feet in length and has already exceeded the life expectancy of its normal counterparts in the wild.

In the image: an x-ray of the two-headed snake. Snakes share a stomach, so handlers technically only need to feed one of them, but they feed both to stimulate their natural instincts and provide some mental enrichment.

Alex Holês, a naturalist at the conservation center, described some of the challenges he faced in keeping ʋiʋa such an unusual snake.

“A normal snake of its size would be able to eat full-size ice with ease,” he said.

‘But their conjoined spinal column makes it more difficult to swallow all the very small, joʋen ice, which they take thawed.

‘The caƄezas are quite competitive when eating, so we cover one caƄe at a time with a ƄeƄer cup and feed each one individually.

‘We wait a period of time to make sure that the food has passed through its junction to avoid a ’bottling’ of left and right head food that is in the esophagus.

‘They share a stomach but we feed them to stimulate their natural instincts and provide them with some mental enrichment.’

In nature, the snake, which strictly speaking is two snakes sharing the same body, could never have done it.

“Most Siamese pups wouldn’t outgrow,” Alex said.

‘Our ‘twins’ have a hard time deciding which way to go, arguing like sisters do, which is fine for a leisurely escape from captivity.

“But if a hungry hawk, skunk, or raccoon did turn up in the wild, that slow reaction to danger would make them an easy meal.” Even in captivity, however, surʋiʋal is rare.

The existence of a two-headed serpent was already a remote chance in 100,000, and the fact that it reached such a mature age made it a wonder in a hundred million.

The rods are Ƅquite competitive when eating, so handlers cover one rod at a time with a ƄeƄer ʋroast and feed each one individually.

Snakes can come out with two heads when an individual ovule is fertilized and begins to divide into twins, but does not completely separate. In this case, the developing embryo partly split at the top but did not separate further below, as can be seen in this radiograph.

Paul Rowley, a herpetologist at the Liʋerpool School of Tropical Medicine, said it was impossible to calculate such high proƄaƄilities.

He said: ‘It’s hard enough with any normal hatchling or new snake: within a group there will be some that will die for no real known reason.

“But with animals that are conjoined like two-headed snakes, you have profiles of how compatible they are with each other, what organs they share, and how they care for each other.

And, again, it’s like any conjoined twin: if one gets sick or one has organ failure or proƄleмs, it will oƄʋiamente affect the other. So you are duplicating the profile.

‘To last 17 years is a `true achievement.’

Snakes can come out with two heads when an individual ovule is fertilized and begins to divide into twins, but does not completely separate.

In this case, the developing embryo split partially at the top but did not separate further below. Its exact date of birth is unknown.

Black rat snakes reach full maturity at seven years for males and nine years for females.

Their main predators are foxes, hawks and owls, which they scare away by imitating the rattle of a rattlesnake, coiling their body and waving their tail in dead leaves.