Rare Mutant Cow Born With Two Heads In One In 400 Million Chance

When it comes to the early stages of development in animals, there’s still a lot for scientists to learn. While there’s the typical life cycle for most animals, sometimes something very unexpected happens that leaves even the most savvy seriously confused.

One of those perplexing moments took place when a rare mutant cow was born with two heads in a one in 400 million chance. This was truly a sight that spectators couldn’t believe, and the science behind this exceedingly rare case may blow you mind.

A Kentucky family was used to seeing the same kind of calfs

While the calfs at their farm came in different colors, the Tarter family in Edmonson County, Kentucky had never seen any of them come with extra heads or limbs.

It was quite the shock to witness the birth of a mutated calf!

Two-headed calfs often have four eyes, four ears, two mouths and two noses

Embed from Getty Images

When the family of farmers saw the latest calf to be added to their household, it was like a horror movie. It wasn’t just a calf with two heads; it had two of everything. Even stranger, the family is by far not the first to experience this ultra-rare kind of calf.

They say good things come in pairs, but maybe this is one of the definite exceptions.

Two-headed animals don’t usually live very long

Embed from Getty Images

Being born with two heads is a condition called polycephaly, which usually occurs in snakes and turtles but can also manifest in other animals, including sheep, cows, dolphins, and even humans.

Sadly, when born with this condition, life expectancy is very short because the organ distribution system is all over the place. This was true for the farmers that witnessed the mysterious birth of the calf. The calf died shortly after being born.

Polycephaly isn’t inherited, it’s a random fluke

Embed from Getty Images

Since none of the animals with polycephaly live to the age of reproductive abilities, this condition cannot be inherited. Rather, it’s much more chaotic than that because it’s up to complete chance.

This condition occurs when a fertilized egg doesn’t split completely into two embryos, a process called “axial bifurcation.” Whatever interrupts the egg splitting seems to happen at random without a specific cause.

This isn’t the same condition as conjoined twins

Embed from Getty Images

While both polycephaly and conjoined twins have similarities, they are a little different. Both stem from embryos that don’t split or fuse all the way.

A key difference is that conjoined twins typically have higher life expectancies because they can share an organ system while having their own brains. Whereas with polycephaly, two bodies might just have a single heart, pair of lungs, and one digestive system.

The Museum of Osteology says that polycephalic bodies could have developed into twins (conjoined or otherwise), but that process is disrupted. No one knows why.

Polycephalic animals are a staple in ancient Greek mythology

Embed from Getty Images

Stemming from the Greek word, “poly,” meaning “many,” and “kephalē,” meaning “head,” polycephaly translates as “born with many heads.”

Greek mythology introduced many fictional creatures with more than one head, including the “Hydra,” which is a many-headed serpent that guards the Underworld, and Cerberus, the three-headed hound that belongs to the ruler of the Underworld, Hades.

While Greek mythology depicts them as very powerful beings, the reality is that they’re the most vulnerable.

Some species defy the odds

Embed from Getty Images

Fortunately, there’s some hope for animals with this condition, and it lies in a cute two-headed turtle named Janus who lives at the Natural History Museum in Geneva, Switzerland.

Janus is the oldest known two-headed animal in the world, who turned 26 in 2023, and shows no sign of slowing down (turtle pun intended).

Janus was named after the two-headed Roman god

Embed from Getty Images

Fittingly named after the two-headed Roman god named Janus, the two-headed tortoise has “two heads, as well as two hearts, two lungs and two personalities,” Reuters reported in 2022.

Janus would never have survived if he wasn’t born into captivity, as he can’t retract both heads into his shell to hide from predators.

Two-headed animals can be found in museums

Embed from Getty Images

While it’s unlikely that people will encounter a two-headed animal by chance, they can see them in displays around the world.

Some of the most noteworthy places to find them include the Museum of Lausanne in Lausanne, Switzerland, and the Ripley’s Believe It or Not! museum in Gatlinburg, Tennessee.