Radical Study Suggests Life on Earth Arose Twice

(sciencealert.com)

21 points | by jnord 1 hour ago

11 comments

  • randomImmigrant 4 minutes ago
    The metabolic science is really cool. The conclusion that life arose twice requires you to buy that proto-cells that grew on these vents and needed those metallic surfaces to survive didn’t count as “life”. Then, free living cells, bacteria and archea, could maybe be argued as having independent paths as they plugged the gaps in their metabolism independently. Same dna, same proteins. Same broad rules of metabolism. Just some alternate paths through chemical space to plug in the metabolic gaps wnd get free from metal surfaces.

    To me, these are clearly not independent paths, but rather the branching of proto-life into two of the great kingdoms of life.

    Then a couple billion years later, one of em ate the other, and rather than destroy it, they both started a symbiotic relationship, and we were off to the eukaryotic race. This is all the same web of life. Not two independent streams.

  • gyomu 16 minutes ago
    The link the site points to seems like a better source (no ads, cites DOI etc, affiliated with AAAS rather than random aggregator website):

    https://www.eurekalert.org/news-releases/1138775

  • andrewflnr 10 minutes ago
    The headline is a little confusing. They're still the talking about a "split" between bacteria and archaea, so even under this theory, the very roots of metabolism and (I'm guessing) genetic code etc still have a single origin.

    Anyway, it does provide a nice reason that bacterial and archaeal cell membranes are different.

  • MarkusQ 7 minutes ago
    Clickbait headline.

    Should be "Life left mineral substrate at least twice" or some such. The research is interesting, but they're playing word games in the telling of it by saying the most recent common ancestor of all life wasn't alive (because it was dependent on a mineral surface), but two of it's children gave rise to lineages that were.

  • pingou 50 minutes ago
    If true, fl in the Drake equation just got much bigger.
    • lanstin 27 minutes ago
      They aren’t saying two totally different independent life creating event, they are saying that the earliest life depending on some external chemicals for parts of what is now covered by metabolism, and the tree of life diverged before those metabolic paths evolved inside the organism, so not totally the same emergence of life twice, but more stuff that reproduces and evolves but doesn’t meet modern standard for life.
      • ch4s3 22 minutes ago
        The science alert article should make this more clear, as its easy to get that impression.
      • pingou 18 minutes ago
        Yes I saw that, but the concept of "life" being quite blurry, I feel it still has an impact on the equation.
      • lanstin 21 minutes ago
        Honestly just more “biology has enormous areas without enough data that need filling in” causing previous generalizations (e.g. the central dogma of information flow being replaced by protein regulation of gene expression, non-coding DNA, even neurons and egg cells being produced thru life) to be overthrown, more than anything, IMO.
  • victorbjorklund 20 minutes ago
    Sounds cool. Anyone with more knowledge that can say if this is really as proven as they suggest and if it is a big thing or not?
  • qsera 10 minutes ago
    Origin of life on earth is not very interesting to me. Origin of life in the universe is where it is at...
    • usrnm 9 minutes ago
      Until we get any tangible proof of life outside Earth, there is no difference
      • ck2 0 minutes ago
        There is likely simple basic life as advanced as bacteria around the universe

        But high level life was likely a series of complex accidents that is not reproducible or would be radically different than us

        One of my absolute favorite PBS Space Time on the subject

        * https://www.youtube.com/watch?v=abvzkSJEhKk

      • qsera 4 minutes ago
        Actually I don't think there is life outside of Earth. I think we are truly alone in this universe.
  • ck2 7 minutes ago
    what's really going to blow your mind is our solar system looked completely different several times with different proto-planets and Earth/Moon is likely made from remnants of those other planets

    * https://en.wikipedia.org/wiki/Formation_and_evolution_of_the...

  • peter_stokes 17 minutes ago
    unfortunately the field of abiogenesis, just like extraterrestrial life, is a lost cause.

    The reality we will never be able to replicate creation of life nor find life on other planets (except via contamination). it's why we've never gotten any closer. and i'm not even religious

    • Qem 3 minutes ago
      Likely we don't need to replicate. We just need to get a sample of life with completely independent origin to our kind of life here on Earth, to study. This way we would be able to separate what are universal properties for any life from historical contingencies specific to us. To have samples of a single kind of life complicates things.
  • theodorejb 23 minutes ago
    The idea that life came about by luck is completely absurd, even more so than thinking that a computer chip was created by chance erosion of a silicone wafer in exactly the right pattern.

    As I see it life was clearly designed by God.

    • lanstin 17 minutes ago
      It’s a big universe and there are a lot of years, so chemical evolution seems like a decent tool for God to use. Much like General Relativity is a more efficient way to rule the world than assigning angels to push the planets thru the sky. And a passing familiarity with birth defects will prove to most hard hearted people that each specific fact of biology is not designed by a loving creator. Unless you believe this messy but gloriously complex universe to be the best of all possible worlds, right up till you lie to your friend, it is difficult to believe whole heartedly in a loving creator.
      • rationalist 12 minutes ago
        I'm not a biblical scholar, but I think the "loving creator" thing was invented by people and not necessarily in the Bible. I'm pretty sure Old Testament God is pretty vengeful.

        Theistic Evolution is wide-enough belief, especially with Protestants.

        • andrewflnr 2 minutes ago
          It is definitely in the Bible. Cynically, God seems to swing wildly between mercy and vengeance, but it's clear he would feel justified in a lot more vengeance than he takes but doesn't because he loves people. Less cynically, he's planning for Jesus and salvation the whole time, and sorta trying to keep the evil from getting out of hand with the occasional smiting. You can make the logic work if you want to.
    • margalabargala 9 minutes ago
      Could you go into why you consider the existence of an invisible (all powerful? Depends which god you mean, you didn't say) being that happens to concern itself with life on Sol's third planet, to be less absurd than what you describe?

      Or is that the joke and I'm missing it?

    • WelkinFolk 18 minutes ago
      I wish I were so vain as to think I'm so special, surely I could never have happened by chance.
    • hollywood_court 4 minutes ago
      Which god?
    • victorbjorklund 19 minutes ago
      Do you reject evolution or do you believe God only created bacteria etc?
    • TacticalCoder 17 minutes ago
      > As I see it life was clearly designed by God.

      Which one? There are so many to choose from...

      And what created that God? I know it's turtles all the way down but still want to know.