4 ms·

Crazy to think we are all here because of that first multi cellular organism splitting over and over and over. Life doesn’t reboot as you say, it is split off

Crazy to think we are all here because of that first multi cellular organism splitting over and over and over. Life doesn’t reboot as you say, it is split off from other organisms whether seed, sperm, rhizome or any other method it’s just cells dividing and spitting off other cells. Mind boggling to me.

anonymouskimmer 4y ago
Yeah. I've known this for years but it really struck me when I typed it out here.
__MatrixMan__ 4y ago
The idea that we all branched from a single ancestral organism has never sat well with me. Whatever started that process, however improbable... Well the universe allowed it to happen. Why expect that the universe wouldn't subsequently continue to let it happen, again and again?
- Izkata 4y ago
  My understanding is this is what happened during the Cambrian explosion.
- anonymouskimmer 4y ago
  Sure, but it would be a completely different tree of life, from a different origin. It's possible our origin was from a community of ancestral organisms, but at some point all terrestrial life that we have discovered so far intermixed enough to create an effective universal common ancestor that we all appear to branch from.
- Tagbert 4y ago
  Because, once it happens in an environment, there is no more room for an alternate life form to arise. A new instance of life would have to compete against the established line and it is unlikely to survive that process.
- samus 4y ago
  Life arising many times in parallel ought to have given rise to multiple trees of life with mutually incompatible biochemistry. Yet, overall life speaks about the same genetic language, and most things work very similar to each other. Life could still have indeed arisen multiple times, however, it probably either merged or got supplanted by its competitors. Life is simply too pervasive to allow for anything else. It would also immediately out-compete any newly arising life. There is some evidence that things like the genetic code, the choice of RNA/DNA nucleotides, and the set of the 20 aminoacids aren't really random. That would not rule out life arising multiple times, but the likelihood that it merged with other lineages would be even higher. Short summary: https://www.science.org/content/blog-post/why-these-amino-acids-anyway https://www.science.org/content/blog-post/why-these-amino-ac... . A more in-depth paper: https://www.sciencedirect.com/science/article/abs/pii/S0378111900004765?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S03781...
  - akiselev 4y ago
    There are a lot of microbes that are unculturable to this day and to my knowledge, no one has really done a proper investigation to see if the universal metabolic molecules like, for example, the hydrogen carriers NAD+/NADP+/NADPH, are truly universal. If we're going to see evidence of multiple trees of life, it'd be in those little details because most of the food chain has to interact with each other. Or fungi and other decomposers can bridge the gap. I think over the span of billions of years, evolution tends to converge too much for the trees to remain very distinct from each other.
    - anonymouskimmer 4y ago
      > There are a lot of microbes that are unculturable to this day Some of this has been solved by literally allowing the microbes to sit in culture for a year or so in order to either wake up from hibernation, or adapt to the culture composition. > see if the universal metabolic molecules like, for example, the hydrogen carriers NAD+/NADP+/NADPH, are truly universal. For anything that's based on DNA or RNA we now do direct sequencing of environmental samples. From this direct sequencing we can pull out individual genes and pathways. > I think over the span of billions of years, evolution tends to converge too much for the trees to remain very distinct from each other. We've got over 20 recognized genetic codes already from existing life. These are highly similar, but this probably points to similar origins instead of convergence.
jwestbury 4y ago
So we're all just orphans from a long-dead init process? :(
- anonymouskimmer 4y ago
  And there's a problem with using a computer analogy. We are survivors(!) from a long-dead process. And have become far more than that process could have ever imagined, if it could have imagined. We are Tron!

anonymouskimmer 4y ago

Yeah. I've known this for years but it really struck me when I typed it out here.

__MatrixMan__ 4y ago

The idea that we all branched from a single ancestral organism has never sat well with me. Whatever started that process, however improbable... Well the universe allowed it to happen. Why expect that the universe wouldn't subsequently continue to let it happen, again and again?

Izkata 4y ago
My understanding is this is what happened during the Cambrian explosion.
anonymouskimmer 4y ago
Sure, but it would be a completely different tree of life, from a different origin. It's possible our origin was from a community of ancestral organisms, but at some point all terrestrial life that we have discovered so far intermixed enough to create an effective universal common ancestor that we all appear to branch from.
Tagbert 4y ago
Because, once it happens in an environment, there is no more room for an alternate life form to arise. A new instance of life would have to compete against the established line and it is unlikely to survive that process.
samus 4y ago
Life arising many times in parallel ought to have given rise to multiple trees of life with mutually incompatible biochemistry. Yet, overall life speaks about the same genetic language, and most things work very similar to each other. Life could still have indeed arisen multiple times, however, it probably either merged or got supplanted by its competitors. Life is simply too pervasive to allow for anything else. It would also immediately out-compete any newly arising life. There is some evidence that things like the genetic code, the choice of RNA/DNA nucleotides, and the set of the 20 aminoacids aren't really random. That would not rule out life arising multiple times, but the likelihood that it merged with other lineages would be even higher. Short summary: https://www.science.org/content/blog-post/why-these-amino-acids-anyway https://www.science.org/content/blog-post/why-these-amino-ac... . A more in-depth paper: https://www.sciencedirect.com/science/article/abs/pii/S0378111900004765?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S03781...
- akiselev 4y ago
  There are a lot of microbes that are unculturable to this day and to my knowledge, no one has really done a proper investigation to see if the universal metabolic molecules like, for example, the hydrogen carriers NAD+/NADP+/NADPH, are truly universal. If we're going to see evidence of multiple trees of life, it'd be in those little details because most of the food chain has to interact with each other. Or fungi and other decomposers can bridge the gap. I think over the span of billions of years, evolution tends to converge too much for the trees to remain very distinct from each other.
  - anonymouskimmer 4y ago
    > There are a lot of microbes that are unculturable to this day Some of this has been solved by literally allowing the microbes to sit in culture for a year or so in order to either wake up from hibernation, or adapt to the culture composition. > see if the universal metabolic molecules like, for example, the hydrogen carriers NAD+/NADP+/NADPH, are truly universal. For anything that's based on DNA or RNA we now do direct sequencing of environmental samples. From this direct sequencing we can pull out individual genes and pathways. > I think over the span of billions of years, evolution tends to converge too much for the trees to remain very distinct from each other. We've got over 20 recognized genetic codes already from existing life. These are highly similar, but this probably points to similar origins instead of convergence.

jwestbury 4y ago

So we're all just orphans from a long-dead init process? :(

anonymouskimmer 4y ago
And there's a problem with using a computer analogy. We are survivors(!) from a long-dead process. And have become far more than that process could have ever imagined, if it could have imagined. We are Tron!