Study shows humans are evolving faster than previously thought

Mar 31, 2015

Photograph: Imagno/Getty Images

By Hannah Devlin

Humans are evolving more rapidly than previously thought, according to the largest ever genetics study of a single population.

Scientists reached the conclusion after showing that almost every man alive can trace his origins to one common male ancestor who lived about 250,000 years ago. The discovery that so-called “genetic Adam”, lived about 100,000 years more recently than previously understood suggests that humans must have been genetically diverging at a more rapid rate than thought.

Kári Stefánsson, of the company deCODE Genetics and senior author of the study, said: “It means we have evolved faster than we thought.”

The study also shows that the most recent common male ancestor was alive at around the same time as “mitochondrial Eve” – the last woman to whom all females alive today can trace their mitochondrial DNA.

Unlike their biblical counterparts, genetic Adam and Eve were by no means the only humans alive, and although they almost certainly never met, the latest estimate which gives a closer match between their dates makes more sense, according to the researchers.

Read the full article by clicking the name of the source located below.

14 comments on “Study shows humans are evolving faster than previously thought

  • I really wish journalists would be more careful with the science. The Adam she refers to is more than just a common ancestor of modern men; he is the most recent common ancestor, along male lines only, of modern people. (Those who lack Y chromosomes still have fathers descended from “Adam”, so are descended from him too.) Take your father (whether you are male or not), and his father and so on, until you reach an ancestor in common with me and everyone else on the planet. Needless to say, a common by-any-route ancestor of all modern humans is much more recent. This “Adam” is the source of today’s human Y chromosomes, just as mitochondrial Eve is the most recent woman to provide us all with our mitochondrial DNA, which only mothers transmit to the next generation. Again, the most recent by-any-route female common ancestor of humans if far more recent than mitochondrial Eve.

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  • Agree with Jos, this is more about a journalist who doesn’t get the science than it is about science.

    As a result, science just lost some of its public profile.

    As someone who struggles to understand biology – I studied Physics and Chemistry before moving to ICT – even I can see that the original study is limited to an unnamed “population”.

    The only question remaining is: Who will spring to Scince’s defence?

    If only we knew a well-known Scientist with impeccable credentials in population genetics …


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  • From what I read in earlier articles, there were large error bars on the dating of both Y Adam and mitochondrial Eve, so not only could they have been geographically far apart, but could have been centuries or millennia apart too!

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  • Jos et. al. sound like they know what they’re talking about.

    “It gives us enormous confidence to have a timeline that is similar,” said Stefánsson. Wouldn’t responsible scientists call for further research on such complex phenomena affected by multiple unknown variables acting on human evolution for hundreds of millenia?

    The study, published in Nature Genetics, put the new age for genetic Adam at between 174,000 and 321,000 years ago. Genetic Eve is thought to have walked the Earth around 200,000 years ago: well within the new error margin for Adam. The study “puts” the genetic Adam alongside the genetic Eve well within the new margin of error, but the “margin of error” is huge. The median age for pinpointing the first y-chromosome Adam courting the genetic Eve after 200,000 years ago is 256,000 years ago [312,000 – 200,000 = 112,000 / 2 = 56,000 years]. The time span is too great to know when these evolutionary events took place with anything approaching scientific accuracy.

    The researchers dated the existence of this man by comparing the Y-chromsomes of 753 Icelandic men, who were also grouped into 274 paternal lines. The researchers used a “molecular clock”, based on the number of DNA mutations that arise with each generation, to estimate Adam’s age.

    Once more the methodology estimates Adam’s birthday falling somewhere within a period of 147,000 years [312,000 – 174,000 = 147,000] suggesting that the “molecular clock” doesn’t keep good time. Apparently the researchers are over-relying on imprecise criteria, contrived “logic” and skewed mathematics in lieu of empirical scientific evidence.

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  • 5
    aroundtown says:

    We can appreciate that science in genetics is giving us verifiable propositions to our origins that were only explained by supernatural nonsense not all that long ago. The ability to sequence DNA provides a clearer more accurate picture that gives us the ability to check the science and update results when new data is plugged into the overall picture.

    Science gives us a fantastic forward thinking process were as religion remains mired down in mythological view points from a bygone era. I wish they could get excited about science too, it is a far more revealing journey that offers greater rewards.

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  • I apologize for the reversal-of digits typo that results in one under calculation above:

    ” The median age for pinpointing the first y-chromosome Adam courting the genetic Eve after 200,000 years ago is 256,000 years ago [ 312,000 – 200,000 = 112,000 / 2 = 56,000 years ]
    The correction should read:

    The median age for pinpointing the first y-chromosome Adam courting the genetic Eve after 200,000 years ago is 260,500 years ago [321,000 – 200,000 = 121,000 / 2 = 60,500 years].

    [312,000 -174,000 = 147,000]. The calculation should read:
    [321,000 – 174,000 = 147,000] Fortunately the answer, 147,000, is accurate.

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  • 8
    Lorenzo says:

    Okay, here’s my comment on the entire story: “meh!”

    I explain: scientific information from generalist newspapers is usually lacking – and surely there’s room to doubt about the accuracy of the Guardian’s article, since it ventilates the hypothesis that Y chromosome Adam and Mythocondrial Eve might be contemporary to each other.
    While the source article is available, I found it unusually obscure. But, from what I was able to get,mit seems that it concentrates on the rate of point mutation in the Y chromosome rather than attempting any sort of dating.

    Hence, my comment.

    Somethg else that’s worth saying is: both these genetical Eve and Adam are extrapolations, they might not be actual individuals and, more importantly, they were far from being the only member of the genus Homo to walk the Earth at the time. They aren’t even related in any way to the concept of “genetic bottleneck”.

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