Imprints of evolution can be see to it among the Haenyeo of South Korea . After generations of forage for food on the seabed , these all - woman divers have fostered several transmissible adaptations that permit them to freedive in chilly temperature and for long periods .
The Haenyeo – literally " ocean women " – are a radical of women who live on Jeju Island , South Korea ’s declamatory island where a unique culture holds on to liveliness . These women , some well into their 80s , plunge up to 10 meters ( 33 foundation ) beneath the sea ’s surface without any breathing equipment , harvesting everything from abalone and ocean urchins to seaweed and octopus .
Although each dive lasts just 30 sec or so , a distinctive forage session can stretch out to four or five hours , demand both endurance and resiliency . Over generations , researchers propose , natural selection may have favored genes that aid Haenyeo women thrive in these utmost status .
The fruits of hard work: A group of Haenyeo selling fresh seafood on Jeju Island, South Korea.Image credit: Charlie Waradee/Shutterstock.com
To research this , scientists led by research worker at the University of California , Berkeley take apart the genomes of 30 Haenyeo divers , 30 non - diving woman from Jeju Island , and 31 mortal from mainland Korea . All participants were at an medium age of 65 geezerhood old , matching the geezerhood of many active Haenyeo . The research worker did n’t arrest at genetic science . They also test the cleaning woman ’s heart pace and blood air pressure at eternal sleep and during “ simulated dives , ” which involved hold their breath while dunking their expression in cold urine .
The study conclude that the Haenyeo may be one of only two known human populations that have evolve genetic adaptations for diving ( the other being theBajau “ sea nomads”of Southeast Asia ) .
Firstly , the researcher ground that residents of Jeju – both Haenyeo and non - Haenyeo – were discrete from people from mainland Korea , intimate that people on the island are descended from the same ancestral universe .
Secondly , the Haenyeo were found to have an regalia of interesting gene variation that may help them cope with the imperativeness of diving . One gene is consort with cold tolerance , which could make the divers less vulnerable tohypothermia , while another cistron is associated with decreased diastolic blood pressure . These variant were found in 33 percent of the population in Jeju and only 7 percent of mainland participant .
“ This connexion may ponder born extract to mitigate the complicatedness of diastolic high blood pressure feel by female plunger while diving through gestation . Since Bajau woman also dive while they ’re pregnant , we wonder whether pregnancy is actually driving a lot of the genetic changes in these diving populations , ” Melissa Ilardo , study generator and geneticist from the University of Utah , explained in astatement .
When researcher copy cold - water dives , all participant have a drop in heart charge per unit as a born reflex response to conserve oxygen . But the Haenyeo stood out : their centre rates descend by an average of 18.8 beats per bit , compared to just 12.6 beat generation per arcminute among non - diving women from the same island . A dull heart charge per unit during nosedive aid the body save energy and stretchlimited atomic number 8 reserves , a crucial vantage when diving repeatedly on asingle hint .
Interestingly , transmissible analytic thinking revealed that the divers and non - divers from Jeju share the same ancestry , suggest this enhanced reaction is n’t inherited . In other words , this special acquisition of the Haenyeo is the remarkable result of lifelong training , not genetic science .
“ Because the Haenyeo have been diving for a very recollective fourth dimension , their spunk charge per unit has been trained to dismiss more . This was something we could actually visually see – we had one loon whose heart pace throw by over 40 beats per minute in less than 15 second , ” take down Ilardo .
woefully , like many of theworld ’s cultural quirks , the Haenyeo custom is sputter to survive . The study explains that “ young women are no longer continuing this matrilineal custom ; the current Haenyeo population , with an average age of around 70 years , may act the last generation of Haenyeo loon . ”
Nevertheless , the genetic and physiologic trait shaped by generations of diving may leave a lasting bequest , not just as a ethnical memory board , but as a scientific imagination . By study how the Haenyeo adapted to utmost physical demands , researchers hope to uncover brainwave that could benefit forward-looking medicament .
“ We ’re really excited to learn more about how these transmitted changes may be affecting the health of the broader universe of Jeju . If we can more deeply characterize how those change pretend physiology , it could prompt the development of therapeutics to treat unlike conditions , such as hypertensive disorder of pregnancy and stroke , ” explain Ilardo .
The subject area is print in the journalCell theme .
