Tibetans May Be the Fastest-Evolving Humans We've Ever Seen

By Andrew Moseman | July 2, 2010 9:13 am

Tibetan_ladyClearly, the people of Tibet must have evolved quickly to tolerate a life spent living at the top of the world. How quickly? A study out in this week’s Science, which compared Tibetans to Han Chinese to see the differences in their DNA, says that the two groups may have diverged no more than 3,000 years ago. If natural selection has changed Tibetans in such a short time, it would be the fastest known example of human evolution. But not everybody is buying this time line.

As DISCOVER noted when a similar study by another team came out in May, natives of the Tibetan plateau seem to survive the altitude because their bodies make less hemoglobin. It’s somewhat counter-intuitive:

In theory higher levels of haemoglobin would be beneficial, because this would improve oxygen transport. But high levels could make the blood thicker and less efficient at carrying oxygen, says Jay Storz of the University of Nebraska-Lincoln [New Scientist]. (Storz writes the accompanying commentary in Science.)

Looking at the differences in genes that regulate that, the team found vast differences between the Han and the Tibetans, with one version appearing in 87 percent of Tibetans studied but only 9 percent of Chinese. However, the assertion by the scientists at the Beijing Genome Institute—that their findings mean the two group broke apart just three millennia ago—has ruffled archaeologists who believe that the Tibetan plateau has been continuously occupied for much, much longer: more like 7,000 to 21,000 years.

For more about all of this, check out Razib Khan’s post at Gene Expression.

Related Content:
Gene Expression: Very Recent Altitude Adaptation in Tibet
Gene Expression: Tibet & Tibetans, Not Coterminus
80beats: Found: The Genes That Help Tibetans Live at the Top of the World
DISCOVER: High-Altitude Determines Who Survives in Tibet

Image: Wikimedia Commons

CATEGORIZED UNDER: Health & Medicine, Human Origins
  • http://www.nicky510.com Crow

    Well, when man is involved, evolution tends to be very fast …

    http://www.nicky510.com/comic/darwins-doggies/

  • Coco Lucho

    ¿What if its not natural? Maybe people just moved far because they could, nobody died.

  • http://drvitelli.typepad.com Romeo Vitelli

    Does it count as evolution when it’s something humans want to make happen? This could just be an example of selective breeding.

  • http://www.nicky510.com Crow

    @3: That’s all evolution really is, if you think about it – selective breeding. In nature an animal might be selectively bred due to environmental pressures and in the dog world it’s due to human preference pressures. But the principle is the same – those with the desired trait thrive and those without it don’t.

  • http://nashich.com radah

    Interesting that their bodies make less hemoglobin, which is anemia. So an iron deficiency & sickle cell anemia makes complex organisms, and the timeline is hilarious! According to Thomas F. Hornbein book, “High Altitude,” the criteria is, “49% of Tibetan and 25% of Han children are anemic.” What if we move them a little higher and see if they’d adapt to no oxygen at all? What if the Tibetan monks are not meditating, but or just tired from the disease? I guess all you need is bad nutrition and you can achieve the same.

  • Stan Tolle

    An explanation needs to be given as to the need for less hemoglobin. Whats going on here is that mosts humans adopt to higher altitude by producing more red blood cells. This is the effect that athletes use when they train at high altitude or use devices to simulate high altitude using things like bed tents. The more red blood cells the higher level of endurance the athlete will have at lower elevations. (The drug EPO does about the same thing.) The only problem is that at the altitudes in Tibet the system goes too far and too many red blood cell are produced. Hence the need for an adaptation that keeps the red blood cell count within healthy limits, which, eventuality the hemoglobin restriction accomplishes. (Master’s Swimmer who trains at 5000 feel evaluation Boulder, Colorado, which also has a large ex-pat Tibetan community. )

  • sati

    how did they know that the evolution took 3000 years? the paper does not say.

  • Joseph

    Selective breeding adds no new information to the dna. Mutations during this process result in offspring that are severely handicapped or which cannot breed beyond their generation or the next generation. This article shows and proves nothing new. What of other cultures that have lived at high altitudes? Are their hemoglobin characteristics any different?

    Evolutionary theory based upon natural selection and mutations has been adequately debunked for over 40 years, yet they are constantly forwarded as plausible theories. Look up Fred Hoyle, Francis Crick, and Stephen Gould to see the lengths that evolutionists have to go to support their ideas. Mathematical lunacy. These three men represent the best scientific minds amongst evolutionists, and their conclusions are all the same: darwinism and neodarwinism is totally false, leaving only puncuated equilibrium (mathematically impossible) and xenospermia (sheer fantasy) as the only possible solutions.

    Most of us in high school and university level biology were never told of the countless experiments that could not lend one shred of support for darwinist and neodarwinist propaganda. That knowledge has always been reserved for the graduate and postgraduate level programs.

    In the words of Fred Hoyle, it is more probable that a fully assembled, perfectly working 747 aircraft would come out of a tornado going through a junkyard, than for natural selection and mutations to have produced what we see today.

  • http://edanswers.moonfruit.com ed

    i studyed this on my own studys on the computer and many of these sites will suggest that we are evolving i also agree with this

  • http://Nisror25Celdorop.bravejournal.com Ujimune Cass

    I don’t know why I hardly open your feeds to my reader. I can load it using my Opera though.

  • http://www.adsense-faq.com/ Adsense FAQ Blog

    I have been absent for a while, but now I remember why I used to love this site. Thanks, I’ll try and check back more frequently. How frequently you update your web site?

  • fred

    oh this study is definitely true.

    the HAN and tibetans are genetically very closely related…. and are basically one people. i knew the Peoples Liberation Army were justified in liberating the tibetans in 1959.

    thanks to the CCP we now know that these two peoples are basically one people, one nation. tibet is a part of China.

    there is no denying, genetics doesn’t lie, Researchers don’t lie.

  • satya

    Why would the scientists in beijing claim that tibetans evolved to survive the altitude in only 3000 years?
    Why would they claim tibetans and chinese separated around that time, when scientists outside say this kind of evolution would have taken longer. i am really hoping the scientists in beijing weren’t paid or forced by the chinese government to publish false statements.
    i hope the chinese government is not trying to make han chinese think tibetans and chinese are genetically very closely related (when it is very likely they’re not), that would make this propaganda.

  • Pema

    Satya, I agree with you. Fred on the other hand, you must be Han Chinese.

    Hi there, I’m Pema, a Tibetan ex pat. My grandparents were exiled from Tibet in the 1950′s; my maternal grandmother lived at the foot of the Potola Palace until her husband was shot dead by Chinese officers. My paternal grandmother, on the other hand, was raped by a Chinese soldier the day she decided to leave her homeland.

    I’m just saying that Tibetans do not consider themselves to be Chinese. We speak our own language, use a different alphabet – based off Sanskrit, not Chinese characters; we have our own national history, religion, and collective identity, and even had an internationally recognized Tibetan passport.

    As far as genetics go, we are different. This study proved that the gene in question, EPAS-1, is found in nearly 90% of Tibetans, but in less than 10% of Han Chinese. Tibetans also carry a D-Haplogroup that is only shared with Andean, and Japanese populations – not Chinese. In my opinion, Tibetan also sounds more like Japanese than Chinese… the first four counting words in both languages are the same! Point is, humans share more than 99.9% of their DNA with chimpanzees. Yet there’s an 80% discrepancy between the Han Chinese and Tibetans in the frequency of a genotype that for most Tibetans, spells out either life or death.

    Using my family as an example, my mother and I were both born in high altitudes in Nepal. Her parents both lived in very high altitudes themselves. We both have low hemoglobin, but with a good diet, the associated Anemia makes very little difference in our lives. We have a lower hemoglobin count, but our bodies are more efficient in the ways that we carry oxygen.

    It is counterintuitive at first, but one must consider the effects of altitude sickness: oxygen deficiency acts as the stimulus for a spike in hemoglobin production. This helps carry more O2 throughout the body, but also thickens and congeals the blood. Over time, the newly climatized individual will suffer from complications from overproduction of hemoglobin. These complications include reduced fertility, and increased infant mortality. In another study done, Tibetan woman with the EPAS-1 gene had an infant mortality rate at .48. Tibetan women without the gene, however, had an infant mortality rate at around 2.53. That is natural selection working right there, selecting only the individuals who are genetically able to adapt to the high altitudes.

    Anyway, it makes sense that we have less hemoglobin in our blood, it just happens that the little hemoglobin we do have is highly effective. The EPAS-1 gene is also associated with super athleticism! Tibetans have 10x the Nitric Oxide as low land dwellers, as well as increased forearm blood flow. In some lame family support of this, my father was a star athlete, my mother was a swimmer, and at some point in my school years, I was a competitive swimmer, runner, gymnast, dancer, and even a cheerleader!

    Anyway, sorry for the long spiel!

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