The last marine nomads: evolving "unusual" bodies

The last sea nomads - the Baobab

In some waters of Southeast Asia, the clear sea is dotted with simple huts made of wood and leaves. Here live the last "sea nomads" on earth - the Baobab.

For thousands of years, they have drifted between the seas of the Philippines, Malaysia, and Indonesia, living on the sea for generations and living in a primitive way, surviving and reproducing at sea. They live their whole life with the amazing talent of diving and fishing for a living, rarely set foot on land, almost no knowledge of modern civilization and everything on land, and even on clocks, calendars, birthdays and so on all do not know. They are most familiar with only the seawater that has accompanied them all their lives. They have no record of their origin, no history, and no fixed name, so the United Nations Educational, Scientific and Cultural Organization named them "Baobab" (also known as "Banjo").

The Baobab is known for its ability to stay underwater for long periods. Due to their long contact with the ocean, they seem to have become one with the sea and seem to be more flexible in the water than on the land, and some of them can even dive to depths of tens of meters for longer periods and catch fish without relying on any diving equipment.

The uniqueness of the group has attracted photography enthusiasts from all over the world to visit and photograph, and some specialized researchers or scientists have come here to get in touch with them, trying to use all kinds of advanced modern equipment to get relevant data from their bodies, to unveil the mystery of this sea nomadic people, to solve their "only with a pair of wooden goggles, they can dive to 70 meters underwater with only a pair of wooden goggles"!

The survival mode of the Baobab people

As "marine nomads", the Baobab spend nearly 60% of their time in the sea every day, which is their only way of survival. They spend their days bouncing between sea huts and small boats called "leap-leap". In line with the habit of "eating the sea by the sea", they will often go out to hunt, dive into the sea frequently, and catch all kinds of fish, shrimp, shellfish, and other marine life as food, in addition to occasionally get to the land to sell and to buy fresh water, other food, and other necessities to maintain their life at sea.

The leap-leap boats are very important to their hunting at sea, and to get more hunting time and better hunting results, they sometimes live directly on the boats and cook meals and sleep on them. Therefore, this kind of boat is also regarded as their second home by the Bayamon people.

The Baobab people, who live by the sea, are certainly very good at the water, and they are arguably the deepest divers in the world.

A normal person can dive to a depth of about 10 meters without any help, while professional divers can dive 15 meters or more with equipment.

The Baobab people do not rely on oxygen masks and other diving equipment, they can dive to a depth of more than ten meters, or even dozens of meters to catch seafood. All their diving tools are only a pair of homemade wooden swimming goggles, and their fishing tools are also very simple - a spear gun used for hunting.

In the process of diving, as the depth deepens, the pressure of seawater on the human body will also increase, which is also true for the Baobab people. When the surrounding pressure is greater than the air pressure inside the ear it will cause the eardrum to compress and the eardrum membrane will sink inward. The eardrum membrane is covered with nerves and the further you dive, the more your ears will feel unbearable pain. In severe cases, the huge pressure of seawater can "burst" the eardrum and even cause people to faint.

To adapt to this situation and live longer in the sea and dive deeper and longer, the Bayamon people break their eardrums when they are young (and then dive into the deep sea to hunt after their bodies have recovered) to reduce the pain caused by the water pressure when diving and hunting.

Many Baobab children catch fish with their bare hands, and it is said that they start learning to dive at the age of 4~5 to catch crabs and lobsters, and dare to catch sharks after the age of 10, although only experienced adults dare to catch large octopus with their bare hands.

Evolution of "unusual" body

The most surprising thing about the Baobab is that they can shut their breath for several minutes in the tens of meters of the high-pressure seabed, plus this whole process also requires a series of physical exertion such as paddling and hunting, experts say that their deep-sea shutdown data has broken through the limits of normal humans.

A team of genetics and genetics scientists from the University of Copenhagen had tested many modern advanced technologies on the Baobab people in an attempt to solve the mystery of their tens of minutes deep dive.

The research revealed, to their amazement, that the Bauhaus do have something different from the norm; their spleens are about 50% larger than those living on the surrounding land. The spleen plays a very crucial role in holding the breath underwater. This is because the spleen can store blood, and blood contains oxygen. When the human body dives to hold its breath, the spleen will contract, thus distributing the reserve of oxygen-rich blood throughout the body, equivalent to an oxygen tank, to provide oxygen to the body.

A larger spleen also means more oxygen can be stored, enabling more oxygen to be available in the blood for diving. This allows Baobab people to be able to hold their breath and dive in the water for longer periods.

So why does the Baobab have such a distinctive "giant spleen"?

The research team found that 25 genetic loci are significantly different from those in the surrounding areas, including the PDE10A gene locus, which is the biggest cause of the "big spleen" in the Baobab people, but this gene locus is not found in other people in the surrounding areas. The scientists confirmed in mice experiments that the PDE10A gene can regulate the size of the spleen.

Based on the data, the research team speculates that the Baobab people are estimated to have moved from land to sea 15,000 years ago, and were forced to adapt to deep-sea diving for a better living, and gradually evolved a body "different" from our ordinary people under long-term "natural selection". One of the most important features is the evolution of a large spleen that can be used for long dives.

The Bauhaus people are often in conflict with neighboring countries. To avoid disputes and protect the fishing resources of the sea, some neighboring governments have guided them to settle ashore to solve the problem of their lack of nationality, so that they can slowly accept modern civilization and their children can receive a good education. Therefore the last sea nomads are now almost disappearing from the sea.

What do you think about the situation of the Bayamon people?