Human Evolution Enters an Exciting New Phase

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If you could escape the human time scale for a moment, and regard evolution from the perspective of deep time, in which the last 10,000 years are a short chapter in a long saga, you’d say: Things are pretty wild right now.


In the most massive study of genetic variation yet, researchers estimated the age of more than one million variants, or changes to our DNA code, found across human populations. The vast majority proved to be quite young. The chronologies tell a story of evolutionary dynamics in recent human history, a period characterized by both narrow reproductive bottlenecks and sudden, enormous population growth. 

The evolutionary dynamics of these features resulted in a flood of new genetic variation, accumulating so fast that natural selection hasn’t caught up yet. As a species, we are freshly bursting with the raw material of evolution.

“Most of the mutations that we found arose in the last 200 generations or so. There hasn’t been much time for random change or deterministic change through natural selection,” said geneticist Joshua Akey of the University of Washington, co-author of the Nov. 28 Nature study. “We have a repository of all this new variation for humanity to use as a substrate. In a way, we’re more evolvable now than at any time in our history.”

Akey specializes in what’s known as rare variation, or changes in DNA that are found in perhaps one in 100 people, or even fewer. For practical reasons, rare variants have only been studied in earnest for the last several years. Before then, it was simply too expensive. Genomics focused mostly on what are known as common variants.

Written By: Brandon Keim
continue to source article at wired.com

5 COMMENTS

  1. Good grief,

    “Most of the mutations that we found arose in the last 200 generations or so. There hasn’t been much time for random change or deterministic change through natural selection,” ???

    That is because it is called evolution by artificial selection. (even I know that). or if you want to look at the bigger picture.

    1. Carbon based life forms start and evolve,
    2. Evolution by natural selection, will eventually produce a species that uses artificial selection,
    3. Any globally dominant species will develop technology.
    4. Technology leads to to artificial inteligence/life which become the dominant life form.
    5a. Carbon based life forms are kept as pets, or
    5B. become extint, or
    5c. destroy the planet. (go back to stage one if the life of the star has not run out)
    (I may have made up the last few bits).

  2. Sjoerd,

    It is unlikely that any terrestrial apocalypse would be so bad as to sterilise the whole planet, so at least there would be some self replicating molecules as a fresh starting point.
    On the other hand I (how shall i put this?) I am open to the idea that artificial life forms will inevitably become the dominant life forms of off galaxies, the main reason being that they would have the advantage of being potentially immortal.

    (BJ,  5d – also sounds good.)

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