Science & Tech

Mutated tribe can swim to bottom of ocean after developing 'sea nomad gene'

Mutated tribe can swim to bottom of ocean after developing 'sea nomad gene'
These Guys Can Hold Their Breath for 13 Minutes

The Bajau tribe of Indonesia have become the first known humans to genetically adapt to diving.

The tribe live an extremely amphibious life, and have now been proven to possess the genetic makeup to do so.

Living off the coasts of Indonesia for more than 1,000 years, the Bajau people live in houseboats, spending a high quantity of their lives in the sea.

As expected, they're highly skilled when it comes to free diving and fishing with spears, as well as possessing extraordinary lung capacities and strong swimming capabilities.

Members of the tribe can dive up to 230 feet using just a set of weights and a pair of wooden goggles.

Speaking to the BBC, Melissa Ilardo, from Cambridge University, said, "they dive repeatedly for eight hours a day, spending about 60 percent of their time underwater."

But it turns out that it's not just their skills that help them achieve this, but also a unique genetic mutation - known as the 'sea nomad gene' - that also aids in their diving ability. They have extra large spleens.

The tribe that evolved to stay underwater longer – BBC

The spleen kicks in when a body is submerged in water, highlighting its key role in the human dive response. The spleen contracts to inject oxygenated red blood cells into the circulation - which can up the oxygen in a human's blood by nine percent.

So it makes sense that by having a larger spleen, Bajau people have a genetic advantage when swimming underwater.

Dr. Ilardo said: "There's not a lot of information out there about human spleens in terms of physiology and genetics, but we know that deep diving seals, like the Weddell seal, have disproportionately large spleens.

"We believe that in the Bajau they have an adaptation that increases thyroid hormone levels and therefore increases their spleen size.

"It’s been shown in mice that thyroid hormones and spleen size are connected. If you genetically alter mice to have an absence of the thyroid hormone T4, their spleen size is drastically reduced, but this effect is actually reversible with an injection of T4."

It's difficult to know exactly how long the Bajau people remain underwater, but some claim to have been under the sea for as long as 13 minutes.

Sadly, their lifestyles are currently under threat.

Their nomadic ways mean they can struggle to gain citizenship, plus commercial fishing has devastated their food supply.

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