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On Wed, 11 Dec 2024 17:27:01 +0000, Martin Harran wrote:
>On Wed, 11 Dec 2024 08:32:42 -0800, erik simpson>
<eastside.erik@gmail.com> wrote:
>On 12/10/24 11:32 PM, Martin Harran wrote:>On Mon, 9 Dec 2024 13:57:43 -0800, erik simpsonThe new life forms don't have any ecological niches available, because
<eastside.erik@gmail.com> wrote:
>
[snip for focus]
>Self-catalyzing time for a strand of RNA is probably on the order of>
minutes. A black smoker need only be present for few years, and the
early earth had a much hotter interior means that there were at least
millions of them. As SJ Gould remarked "life may be as common as
quartz". Indeed. All you need is hot water and a thermal or chemical
gradient and you're good to go.
If that is the case, why have we not seen any new life forms develop
from scratch in the last several billion years with every form of life
we know descending from a single origin?
>
I know the typical response is that in the early earth, there were
possibly numerous life forms with one dominant one devouring the
others but that seems a bit of a stretch; it doesn't explain why there
is no trace of anything developing in later stages and no one has ever
been able to create laboratory conditions that have allowed new life
to develop. Miller-Urey got as far as amino acids but that is a long
way from a life form.
>
Just to be clear, I am not endorsing MarkE's arguments; I'm simply
challenging the Gould statement and the "all you need" comment.
>
they're already occupied by fully adapted life. You'd have to have some
strong advantage to prevail (it does happen, but rarely).
Hmmm .... lots of niches for the development of the many many millions
of life forms that have evolved over billions of years but no niches
available for new forms to evolve. As I said, sounds like a bit of a
stretch.
Only if you fail to think about it.
For new life it evolve, it has to have a significant supply of ready
food/energy to power its emerging metabolism. The initial chemical
hypercycles would not be expected to be efficient in the way they
convert
their primary energy source into the synthesis of derived chemical
structures like specific lipids and polymers.
>
Moreover, any such reservoir of protolife would be a rich feeding ground
for life that had already evolved.
>
That is completely consistent with life as we know it now where other
life competing for the same resources is usually the top threat to its
continued existence.
>
Indeed, the supposition that life as we know it is the result of an
early
"winner" having driven all other competitors into extinction as part of
a
race to consume available resources was put forward at least by the
1950s
by scientists observing life.
>
So it's not a stretch or facile excuse. It's what any reasonably
thoughtful biologist concludes. The existence of cellular life
effectively
precludes a subsequent independent re-emergence of cellular life. It
would
be like expecting a child with no knowledge of current racing cars to
build a racing car that could win a race against a fleet of well evolved
racing cars.
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