Why Indonesia's Bajau people can stay submerged under water longer than you or me


Originally published at: https://boingboing.net/2018/04/20/a-genetic-adaptation-allows-in.html


Hmmm it got me thinking about genetic adaptation to high altitudes but this looks totally different. The spleen is storing charged up red blood cells. These Indonesian people really should look at getting in to professional cycling. Blood doping is illegal. Changing your DNA to give you a high capacity spleen will probably be illegal at some point, but being born that way should be perfectly fine.

I wonder how they would go with mid length running events, maybe from 200 metres to 1km? They should be able to stay aerobic much longer than other runners.

Also space travel. If your square lithium hydroxide canisters don’t fit the round holes in your vehicle, these guys can go longer without breathing. Thirteen minutes in a pressure suit without any life support at all is long enough to get serious work done.


I wonder if this sort of spleen enlargement carries any of the risks of rupture they say are associated with trauma to pathologically enlarged spleens; or is whatever splenic structure proportionally enhanced?


So a larger spleen gives an edge for survival (and possibly attractiveness when it brings home the bacon, as it were.) I wonder how many generations of selection it takes for an adaptation like this to become ubiquitous in a population. How long have these folks been freediving??


That was a remarkably clear and consise exspleenation of the phenomenon.


Finding this kind of stuff on Boing Boing is why I love it. This is good. It’s interesting, challenging and represents a worthwhile characteristic of people. Fuck stories about orange assholes and greed mongers.


Some reaaaal digging through the wikipedia article puts the ethnogenesis of the Sama-Bajau people at around 800 AD.


My guess is that 3000 years ago there was more selective pressure in favor of diving ability than there is now.


Reading this article automatically made me think of this image:


Did some digging and sure enough, he’s Bajau:


Hmm… is this somehow connected to the expression “to vent one’s spleen”?


Stories where the key sentence is “why people of group $X do activity $Y” always make me a little uncomfortable.

I understand that there are differences between populations, but historically we have been terrible at dealing with this kind of information.


They use highly efficient scuba diving equipment?


I have known that people can train themselves to hold their breath and avoid the spasms that normally stop us after about two minutes. The record has slowly gone up to almost 12 minutes, according to…

There are longer breath-holding records up to 24 minutes but they mostly involve pre-breathing with pure oxygen. It seems the the Bajau 13 minutes is not recognised by the Guiness World record people, which is a little odd. I probably believe they can do this. If they spend their lives in the water, then you might expect them to be somewhere at the top of the breath-holding league, and their 13 minutes is only a bit over the Guiness figure.


Do you know what the scientific word is for a group of geographically-isolated people that have developed a genetic adaptation that confers an evolutionary advantage? A race. Yeah, I know.


How frigging cool is that?

I’m holding my breath right now.


And the show Jago: A Life Underwater on Netflix tells a great story of the life of a Bajau man.



Secret backstory of Non-Essential Systems Maintenance Chief Ryley Robinson?


I didn’t know that one. The best example I could think of is the Grendel from The Legacy of Heorot. Its an alien apex predator which can release oxidizer into its bloodstream while attacking prey. In a later book a grendel uses a trickle of stored oxidizer to survive an extended swim through a flooded cave network.


Ok but how about now?


You know this is a really interesting thing. John Varley and Peter Watts have both written about people replacing one lung with a prosthesis which enables them to live without breathing. But you have to lose that lung to make space. People can live without a spleen though. So what about making an artificial spleen, which uses an external supply of oxygen (and probably external power) to efficiently feed external oxygen into the body. You could save a lot of gas that way, and lose a lot of the infrastructure which is needed to turn a tank of liquid oxygen into a breathable atmosphere.