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Scientists May Have Found the Earliest Evidence of Life On Earth (sciencemag.org)

Posted by samzenpus on from the in-the-beginning dept.

sciencehabit writes with news that UCLA scientists have found evidence that life likely existed on Earth at least 4.1 billion years ago, 300 million years earlier than previously thought. Science reports: "When did life on Earth begin? Scientists have dug down through the geologic record, and the deeper they look, the more it seems that biology appeared early in our planet's 4.5-billion-year history. So far, geologists have uncovered possible traces of life as far back as 3.8 billion years. Now, a controversial new study presents potential evidence that life arose 300 million years before that, during the mysterious period following Earth's formation. The clues lie hidden in microscopic flecks of graphite—a carbon mineral—trapped inside a single large crystal of zircon. Zircons grow in magmas, often incorporating other minerals into their crystal structures of silicon, oxygen, and zirconium. And although they barely span the width of a human hair, zircons are nearly indestructible. They can outlast the rocks in which they initially formed, enduring multiple cycles of erosion and deposition."

10 of 71 comments (clear)

  1. Re:Where's the evidence!? by The+Real+Dr+John · · Score: 4, Interesting

    It's tough to get a good discussion on biology going here at /. This is a really interesting find if it holds up. The structures they found are interesting, and have characteristic features that don't seem like they could have been produced by geological means. But still, I think they have their work cut out for themselves to find more samples, and confirm that these aren't just some very odd geological artifacts.

    --
    A brain is a terrible thing to waste... Mind? That's debatable.
  2. No one reads the article so... by burtosis · · Score: 5, Insightful

    Let's not even include a link to it!

    1. Re:No one reads the article so... by Anonymous Coward · · Score: 2, Informative

      The link is there. You wouldn't know it by looking at it but "(sciencemag.org)" is actually a clickable link. UX ftw!!!

    2. Re:No one reads the article so... by burtosis · · Score: 3, Informative

      Right that's what I get for viewing on my mobile device before coffee. Still it's the traditional poorly referenced third party article instead of the actual source article but what else do you expect?

  3. Actual article link by burtosis · · Score: 4, Informative

    link to article

  4. UCLA News by ath1901 · · Score: 3, Informative

    Haven't found any scientific article yet but here is the news page from UCLA:
    http://newsroom.ucla.edu/relea...

    In short, they found graphite in a crystal and the graphite has a carbon 12 to carbon 13 ratio which indicates biological origin.

    So, the current status is "plausible" but if someone comes up with another explanation it is "busted".

  5. Right in the middle of the Hadean period. by dotancohen · · Score: 4, Insightful

    Note that 4.1 Ga is right in the middle of the Hadean period, when the Earth was still settling into layers and the crust and oceans were just forming. No distinct core or mantle yet, and the moon was a ring of rock encircling the Earth. This is half a million years before plate tectonics, before even prokaryota (micros without cell nuclei) developed.

    These clues might just tell _how_ cellular reproduction and upwards energy gradients (i.e. life) began, not just _when_.

    --
    It is dangerous to be right when the government is wrong.
    1. Re:Right in the middle of the Hadean period. by dotancohen · · Score: 2

      This perspective hints that the role of the Moon and plate tectonics in the formation of life is overrated.

      I'm not sure about plate tectonics, but the role of the moon was, so far as I understand, to allow _complex_ life to develop. A few self-replicating proteins don't need stable seasons and tides, but eukaryotes and multi-cellular life do benefit from the repeating (and replenishing) energy gradients.

      --
      It is dangerous to be right when the government is wrong.
  6. Re:Where's the evidence!? by Anonymous Coward · · Score: 2, Funny

    A wild Q'ran appears, burns your bible, wipes your mind clean of any education you may have had but as compensation gives you two 9 year old brides.

  7. Panspermia by PopeRatzo · · Score: 2

    I'm not saying it was aliens, but...

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    You are welcome on my lawn.