The Remarkable Story of the Bajau Sea Nomads

By Robin Mei - February 04, 2018
Credits: Image: Claudio Sieber / Caters News

Who Are the Bajau?

Credits: Image: Claudio Sieber / Caters News

The Bajau people of Southeast Asia, commonly known as “sea gypsies” or “sea nomads,” are not just a unique cultural community who have lived offshore for at least a thousand years, but a kind of “medical phenomenon” too.

Their particular lifestyle, which has remained unchanged for centuries, has apparently triggered a natural selection process that has made them the best freedivers in the world. The Bajau’s bodies are literally genetically adapted to life on — and in — the sea.

Source: ‘Sea Nomads’ Are First Known Humans Genetically Adapted to Diving

What Can They Do That's so Impressive?

Credits: Image: Claudio Sieber / Caters News

While the average person can hold their breath underwater for seconds, the Bajau can do the same for much longer — up to 13 minutes in a single dive. At the same time, the depths to which they dive are quite remarkable and can reach depths of 60 meters (200 feet).

What makes these people so unique? In a search for an answer, scientist Melissa Llardo from the Center for Geogenetics at the University of Copenhagen traveled to Southeast Asia to meet the Bajau nomads.

Putting the Pieces of the Puzzle Together

Credits: Image: Torben Venning

Inspired by studies done on seals and other marine mammals who spend most of their lives in deeper waters that showed all of these creatures have disproportionately large spleens, Llardo wondered if similar manifestations could be found in humans whose lives have been closely attached to the sea for a very, very long time.

The remarkable results of her study were published in the journal Cell, and the story behind them it is incredible.

Source: Physiological and Genetic Adaptations to Diving in Sea Nomads

Diving into the Research

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Llardo has traveled to Indonesia to learn more about the Bajau people and their incredible abilities.

“I wanted to first meet the community, and not just show up with scientific equipment and leave,” Llardo explained in an interview for a National Geographic article about the study she conducted.

“On the second visit, I brought a portable ultrasound machine and spit collection kits. We went around to different homes, and we would take images of their spleens.”

Source: ‘Sea Nomads’ Are First Known Humans Genetically Adapted to Diving

Answers Found in an Unlikely Organ

Credits: Image: Scubazoo / Caters News

During her study visit to the area, she also conducted control research and collected data from another group of peoples called Saluan, who unlike the Bajau, live on the mainland of Indonesia.

Comparative analysis of the two groups of samples has shown that the Bajau have up to 50 percent larger spleens than those of Saluan people, which indicated that something was going on at a genetic level. Llardo and her team were determined to find out why that was.

The Genetic Edge of the Bajau

Credits: Image: Claudio Sieber / Caters News

It turned out that the Bajau are the first humans who have genetically adapted for diving. Just like many of the creatures they fish and hunt underwater, these sea nomads have made the ocean and its depths their home too.

Most people from the Bajau community spend almost 60 percent of their (working) time underwater, and their bodies are perfectly engineered for that. Even those who don’t dive at all share the same physical characteristics of the frequent freedivers.

Under Pressure

Credits: Image: Scubazoo / Caters

All of the observed Bajau had enlarged spleens. The size of this organ is important as it serves as a reservoir for red blood cells which carry oxygen through the body.

When a person is submerged under water, their body automatically initiates a diving response: their heart rate slows down and their spleen contracts to push out additional red blood cells so the flow of oxygen to the brain and other organs increases.

There's More to This Than Just a Big Spleen

Credits: Image: Claudio Sieber / Caters News

The DNA analysis showed other genetic changes. The most prevalent gene variations among the members of the Bajau population is in a gene related to T4 hormone produced by the thyroid gland. T4 affects the metabolic rate and helps the body to fight low oxygen levels.

Another gene variant among the Bajau helps the body to squeeze out blood from the limbs and other non-vital body parts when there is low oxygen so that the brain, heart and lungs can keep functioning.

These Differences Make Them the Best

Credits: Image: Torben Venning

These finds point to the same probable conclusion: nature and its mechanism of natural selection have helped the people of the Bajau to become the best freedivers in the world, with an ability to dive longer and deeper than the majority of the planet’s population.

These discoveries are not just important for the understanding of the Bajau, but they could be crucial for research on treating hypoxia, the deficiency of oxygen in the tissues due to disease or injury.

Preparing Their Bodies for the Deep Dives

Credits: Image: Claudio Sieber / Caters News

Since diving at higher depths is a daily activity for most of the Bajau people, they tend to make it as easy and painless as possible by deliberately rupturing their eardrums at a relatively early age so excessive water pressure due to the depths of their freedives does not become an issue later on.

Bajau children learn to swim almost before they learn how to walk and it takes them about a week to recover befor they are ready to dive again.


How Did the Bajau Evolve?

Credits: Image: Claudio Sieber / Caters News

In order to better understand why these particular people have developed such incredible physical characteristics which have made them a kind of superhero of the deep sea, it is important to learn more about their origin, culture and a way of life that goes back to at least the 13th century.

A very complex set of circumstances has led to these incredible changes in the Bajau genes, and none of that happened overnight.

A Foggy Origin Story

Credits: Image: Fairuz Othman

The Bajau people belong to the Austronesian ethnic groups of Maritime Southeast Asia, but their exact origin is not entirely clear. The Bajau mostly reside in the waters of the Sulu Sea and they often drift between Indonesia, Malaysia and the Phillippines.

They remain unattached to any of these countries, at least in any sort of traditional or official sense, coming ashore only when they absolutely need to — usually to trade, build new boats or bury their dead.

Source: The Bajau People: “Sea Nomads” Of The Far East

Life on the Sea

Credits: Image: Fabio Achilli

Many of the Bajau people reside in stilted dwellings on the water or on lepas, long houseboats built from ubar suluk (red araya wood) that can be found on the islands.

The Bajau use lepas as their homes, their fishing boats and means of transportation. The entire family and community life of the Bajau people takes place on lepas.

These longboats often serve as wedding venues too, and the stages for the Bajau’s traditional celebrations.

Source: The Traditional Lepa Boat

When a Boat Becomes a Home

Credits: Image: Claudio Sieber / Caters News

A typical lepa boat is about five to seven meters (17 to 25 feet) long and up to two meters (6.5 feet) wide. It has a harp bow in the front called a tujjah, and two sails —  lamak bua’an (bigger sail) and lamak kapi (smaller sail).

The middle portion of a lepa is usually enclosed and covered with a palm leaf rooftop. It contains the living quarters anda small storage space for cooking pots, water jugs and fishing tools.

Born to Fish

Credits: Image: Claudio Sieber / Caters News

The importance of fishing for this community is also captured in the Bajau folklore and mythology. One of their most important legends tells the story of a giant man called Bajau who helped the tribe of people he was named after harvest what they needed from the sea.

Bajau would go into the water and lay down, causing a wave of fish to be thrown onto the shore where it could be collected. Even when other envious tribes tried to kill him, he managed to survive their poisonous arrows.

Keeping Traditions Alive

Unfortunately, the tradition of building this type of boat is slowly being lost. Knowledge and skills needed for this craft once mastered by Bajau fathers are now rarely handed down to their sons.

However, festivals like the Regatta Lepa seek to preserve the tradition and heritage of the Bajau people. Every April, the Bajau and their lepas gather in Semporna, a small town along the east coast of Sabah, for a big celebration of the Bajau seafaring lifestyle.

The Ceremonial Side of the Bajau

The Bajau people are known as a festive and vibrant community which cherishes its cultural distinctiveness and freedom from outside influence. They love to wear very colorful clothes, usually made from dastar fabric, but particularly interesting are their ceremonial outfits.

Matrimonial ceremonies feature the bride and groom wearing dazzling and bold outfits. The higher the two merging family’s status in the community is, the richer and brighter their garb will be.

Married Life

Credits: Image: Claudio Sieber / Caters News

Once married (which still occasionally happens through an arranged marriage), most of the newly-wed Bajau continue to live the same way as their parents: drifting on the open water, in a search of fish, shrimp and sea cucumbers (known as trepang), a delicacy in Southeast Asia.

The way they fish and catch the rest of their sea prey is also a very traditional one — deep diving with nothing but wooden goggles and a hand-made spear.

The Use of Man-Made Tools

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Diving comes naturally to the Bajau people, but even with the changes their bodies have made they occasionally use tools to help them out while fishing and hunting.

They usually wear wooden goggles to help them see better in the water at the depths that they are able to reach, and occasionally a pair of woolen gloves if they have them to protect their hands while harvesting clams or digging around coral to get at shellfish.

Sometimes the Bajau Can Take Things Too Far

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Besides traditional spears, the Bajau have also adopted modern tools like tire irons and other metal objects that can help them to dive deeper and make their hunt more efficient.

Sadly, with the introduction new tools they have also embraced some highly risky methods, from conventional diving with inadequate compressors using garden hoses to pump air to the diver an the dangerous practice of using dynamite or potassium cyanide to kill fish.

Source: The last of the sea nomads

Damaging the Environment

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This environmentally harmful practice was introduced by Hong Kong fishing boats, but it swiftly spread across Southeast Asia. Many, including the Bajau, started to use plastic bottles filled with cyanide poison to blow deadly clouds at schools of fish so they could easily collect them.

All of this is an attempt to cash in on the demand for reef species such as grouper, a market that as of 2010 was bringing in nearly $800 million (US) per year.

Some Bajau Are Moving Inland

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The story of Bajau is still being told, but many other tales and lore are not being passed on to the next generation. Even the most traditional members of the Bajau community are starting to change their ways.

The boat-building craft is slowly dying and lepas are being replaced by the standard commercial fishing vessels. In addition to this, more and more of the Bajau people are settling on land and go to the open sea only to fish.

Riding Horses Takes Over From Deep Diving

Credits: Image: Fabinda

There are subgroups of the wider Bajau ethnic community who have entirely abandoned the seafaring life, some even as long as 200 years ago. Many of them now live in Sabah, a Malaysian state in the northern part of Borneo.

Their once sea-wandering lifestyle has been exchanged for a life of farming and cattle breeding. They are now often called “cowboys of the east” due to their equine mastery that has replaced their renowned diving skills and abilities.

What's Next for the Bajau?

Credits: Image: Claudio Sieber / Caters News

There is still hope for the Bajau people and their way of life at sea. Despite forays onto land, the sea is still the very center of their identity. The incredible connection these people have with the ocean is one that we are unlikely to ever see again.

Yet if their culture disappears, their genes won’t, not for a very long time. They will still be the people who were “made” for life both in, and on, the water.