Meet the Bajau sea nomads — they can reportedly hold their breath for 13 mi

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https://youtu.be/JDCpeLIJYy4

https://www.nationalgeographic.com/science/article/bajau-sea-nomads-free-diving-spleen-science

'Sea Nomads' Are First Known Humans Genetically Adapted to Diving

Meet the Bajau sea nomads — they can reportedly hold their breath for 13 minutes

The Bajau people's nomadic lifestyle has given them remarkable adaptions, enabling them to stay underwater for unbelievable periods of time. Their lifestyle, however, is quickly disappearing.



KEY TAKEAWAYS

The Bajau people travel in small flotillas throughout the Phillipines, Malaysia, and Indonesia, hunting fish underwater for food. 

Over the years, practicing this lifestyle has given the Bajau unique adaptations to swimming underwater. Many find it straightforward to dive up to 13 minutes 200 feet below the surface of the ocean. 



Unfortunately, many disparate factors are erasing the traditional Bajau way of life.


Picture yourself holding your breath. How long can you last underwater? A minute? Two? You probably imagined yourself sitting a foot or so beneath the surface of a pool during this exercise, but consider how long you can hold your breath actively swimming as deep below the surface of the ocean as you can go.

This would probably look like maybe 30 seconds of swimming down followed by a rush to the surface.

The Bajau people of the Philippines, though, according to reports, could quite confidently imagine swimming 200 feet below the ocean surface for up to 13 minutes.


These abilities aren’t merely the result of dedicated training. The Bajau people have lived their lives at sea for generations, so much so that they’ve developed special adaptations to their oceanic lifestyle.


UNIQUELY ADAPTED TO A UNIQUE LIFE

The traditional Bajau lifestyle is mainly spent on boats organized into flotillas that meander around the waters of the Philippines, Malaysia, and Indonesia. Here, they engage in subsistence hunting, spearing fish for food when the need arises. In a given day, a Bajau individual might spend five hours underwater in total, where they are complete masters of their environment. The only equipment they use are handcrafted wooden goggles and a speargun.



In order to facilitate their freediving lifestyle, some Bajau deliberately puncture their eardrums to deal with the intense pressure they experience underwater. “You bleed from your ears and nose, and you have to spend a week lying down because of the dizziness,” said Imran Lahassan, a Bajau man, to The Guardian. “After that you can dive without pain.” Bajau who undergo this procedure tend to become hard of hearing in their old age.
Simply diving frequently also helps them become more capable swimmers. The lung wall and abdomen become more compliant, and diaphragms become stretchier. But researchers have discovered that the Bajau also possess a useful genetic trait. Specifically, the Bajau possess variants of the PDE10A gene and the BDKRB2 gene, variants that are absent from their closest neighbors, the Saluan, who do not live their lives at sea.
This change manifests itself in a few ways. For one, Bajau have spleens that are 50 percent larger than the Saluan. Spleens aren’t necessary for survival, but they do play a role in the immune system and act as a kind of filter for the blood, removing old red blood cells and recycling iron. But crucially, the spleen holds a reserve of blood. When mammals dive underwater, the spleen contracts, distributing the reserved, oxygen-rich blood throughout the body. So, a bigger spleen means more available oxygen when diving.


Furthermore, the genetic variants that the Bajau possess is associated with another feature of the diving response: peripheral vasoconstriction, although this phenomenon hasn’t been directly observed by researchers. The unique genetic profile of the Bajau may enable them to better constrict noncritical areas of their vascular system. In essence, this means that less blood is used in the more external parts of their bodies such as their limbs, and more blood is sent to critical areas like the heart, lungs, and brain, enabling longer dives.


A WAY OF LIFE AT RISK

Unfortunately, the nomadic lifestyle of the Bajau people has been dying out for years. Many factors are working against them. First, nomadism itself isn’t compatible with modern states, and many Bajau have been made to settle on land or in stilt villages built on shallow seas. What’s more, some Bajau engage in fishing practices that directly harm the environments they rely on. Some divers crush up potassium cyanide tablets into plastic bottles full of seawater, which can then be squirted at fish to stun them for an easy catch. The practice easily damages sensitive coral reefs that form the environment for many of the fish species they rely on for food. Industrial fishing, too, is depleting the fish stocks they used to survive. Altogether, the changing world is quickly erasing the Bajau way of life.





How Asia's Super Divers Evolved for a Life At Sea

Scientists are starting to uncover the genetic basis of the Bajau people’s incredible breath-holding abilities.

By Ed Yong

The Bajau people of Southeast Asia are among the most accomplished divers in the world. In the summer of 2015, Melissa Ilardo got to see how good they are firsthand. She remembers diving with Pai Bayubu, who had already gone fairly deep when he saw a giant clam, 30 to 50 feet below him. “He just dropped down,” Ilardo recalls. “He pointed at it, and then he was there. Underwater, the Bajau are as comfortable as most people are on land. They walk on the seafloor. They have complete control of their breath and body. They spear fish, no problem, first try.”


Sometimes known as “sea nomads,” the Bajau have lived at sea for more than 1,000 years, on small houseboats that float in the waters off Indonesia, Malaysia, and the Philippines. Traditionally, they came ashore only to trade for supplies or to shelter from storms. They collect their food by free diving to depths of more than 230 feet. They have no wet suits or flippers, and use only wooden goggles and spearguns of their own making. Sometimes, they rupture their own eardrums at an early age to make diving easier.
Not all of them dive; some avoid it entirely. But those who do take the skill to an extreme. Each day, they’ll spend more than five hours underwater, capturing between two and 18 pounds of fish and octopuses. The average dive lasts for just half a minute, but the Bajau can hold their breath for far longer. In the clip below, from the BBC documentary Human Planet, a man named Sulbin stays underwater for almost three minutes. “I focus my mind on breathing,” he told the BBC. “I only dive once I’m totally relaxed.”



Their abilities are almost certainly shaped by experience and training. But Ilardo has found evidence that they are also genetically adapted to life in the sea.
Over three trips in the summer of 2015, she got to know people from the Bajau village of Jaya Bakti in Indonesia. She explained her work as a geneticist, went diving with them, and learned about their lifestyles. On one trip, she brought along an ultrasound machine, and scanned the bodies of 59 villagers. That’s when she realized that the Bajau have unusually large spleens—50 percent bigger than those of the Saluan, a neighboring group who barely interact with the sea.




What group of people can stay underwater for a long time?


The free-diving Bajau people of Southeast Asia, or "sea nomads," can hold their breath for minutes at a time -- possibly due to their unusually large spleens.



The people of Sama-Bajau community can stay under the water for 13 minutes at a depth of 230 feet (70 meters). For how long can humans hold their breath underwater? Normally, average healthy humans can hold their breath for 3-4 minutes. Some gifted persons can hold their breath a little longer.



Spleen


Synonyms: Lien

The spleen is the largest organ of your lymphatic system, a subdivision of the immune system. Its network of trabeculae, blood vessels and lymphoid tissue provides an environment in which white blood cells (lymphocytes) proliferate while old damaged red blood cells (erythrocytes) are recycled.
Although it may seem dispensable as it is possible to live without it, the spleen is constantly filtering the blood in order to detect the presence of microorganisms. If you find yourself in the emergency room, the spleen also holds a large reservoir of blood which can be pumped back into circulation if needed.

Spleen

The spleen is a small organ inside your left rib cage, just above the stomach. It’s part of the lymphatic system (which is part of the immune system). The spleen stores and filters blood and makes white blood cells that protect you from infection. Many diseases and conditions can affect how the spleen works. A ruptured (torn) spleen can be fatal.