Rare human body features you didn’t know exist

With billions of people walking on this planet, it's no surprise that we're all unique. And while we have many common features in our bodies, it's only natural that there are some that hold characteristics that are truly rare and different. But some of these differences are especially extraordinary on a biological level. From a rare blood type to additional ribs, and an immunity to sleep deprivation, you'd be surprised to learn that these body features actually exist.

Click on to discover some of the rarest bodily features very few people have.

Immunity to sleep deprivation

People with a mutation of the DEC2 gene can sleep around six hours a night and still be completely fine. Those with the condition are known as familial natural short sleepers (FNSS).

Pitch perfection

Having "perfect pitch" doesn’t mean one is a great singer. This rare condition allows people to precisely identify musical notes, which means they can hear a D minor and name it on the spot.

Stay underwater up to 10 minutes

If you have a hard time holding your breath for 30 seconds underwater, imagine 10 minutes! However, the Bajau, sea nomads in Southeast Asia, have this skill. This is because they evolved an extra-large spleen that serves as a repository of oxygen-rich blood cells.

Being truly even-handed is a rare thing

We live in a right-handed world, with around 90% of people being right-handed. Most of the remaining 10% are left-handed. But then there are a small number of ambidextrous folks, those who can can perform all tasks equally well with either hand.

Advanced color vision

The average eye has three cones, which means you can recognize colors in the red, green, and blue spectrums. However, there are also tetrachromats who have four cones in their eyes. They can see ultraviolet shades, allowing them to appreciate 100 million distinct colors.

Ability to survive at high altitudes

If you've hiked up a mountain, then you know it's brutal. So how do indigenous groups like Tibetans survive at altitudes as high as Mount Everest? Researchers believe that because their ancestors lived in high regions for thousands of years, they developed red blood cell adaptations that make it possible to survive with low levels of oxygen.

Built-in compass

Researchers at the Queensland Brain Institute discovered that a person’s ability to find their way is learned gradually, and that the brain eventually becomes attuned to a sense of direction in new environments.

Fingernails and toenails without nails

There's a rare condition that results in a person lacking some, or all, of their nails. It's called anonychia congenita, and it happens because of a mutation in a gene that controls the manufacturing of a protein called R-spondin-4. This is the same gene that tells the body's tissues and cells how to develop.

Having a long toe isn't an issue

If you have a second toe that is larger than your first, then you are part of the 22% of people who have Morton’s toe. This feature is believed to be an evolutionary remnant of pre-human toes.

An extra rib near the neck

More prevalent in women, this extra rib can sometimes be spotted near the cervical spinal region. It can vary in size and only causes discomfort if it grows.

A right-sided heart

Known as dextrocardia, around 1% of people have this condition. People with a right-sided heart can live perfectly ordinary lives, but on occasion they can suffer some side effects like breathing difficulties and a compromised immune system.

The deficiency that keeps away heart diseases

Everyone has a gene called proprotein convertase subtilisin/kexin type 9 (PCSK9). However, a small number of people carry a lesser amount. This deficiency reduces the risk of heart disease and cholesterol.

Long palm muscles that are passed down from our ancestors

Known as palmaris longus, it was basically a muscle that helped our ancestors climb trees. And while we don’t use it anymore, some people still have it.

When a bad hair days lasts for years

While most of us have the occasional bad hair day, there's an actual condition called "uncombable hair syndrome." It's the result of genetic mutations, which affect proteins that form the hair shafts on the head. Instead of the usual rounded cross-section, people with this syndrome grow hair with a cross-section that makes it impossible for the hair to be combed flat. The hair will then stand out from the scalp.

It's fine to have an extra finger

About one in 500 infants are born with an extra finger or toe, a condition called polydactyly. Extra digits can be removed surgically, but a study found that in some cases having six fingers on a hand can be beneficial. For example, one can perform more complex movements, and also do some tasks with one hand that normally require two.