
First life: The search for the first replicator (2011) - curtis
http://www.newscientist.com/article/mg21128251.300-first-life-the-search-for-the-first-replicator.html?full=true#.VH7FHIflsUF
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aethertap
> If there ever was a self-replicator, it has long since disappeared.

This is something I've wondered about ever since reading "Life's Ratchet" \-
if it was possible back then for a molecule to be self-replicating, then it
seems like it should still be possible today (maybe with a different
molecule), and therefore it seems possible or even likely that it's already
happening all the time all around us. It's fun to think about seeds for new
evolutionary paths being generated constantly at a scale so tiny we can barely
perceive them. Maybe we will start finding instances of replicator molecules
in all sorts of places once we know what to look for. If we master the
chemistry to the point where we could design replicators for other places, we
might even be able to kick off life in the nicer neighborhoods of our solar
system.

~~~
maxerickson
Life scavenges a lot of the available chemical energy, making it less likely
for a replicator molecule to interact with the necessary raw materials.

edit: It also might tend to scavenge replicator molecules themselves.

~~~
aethertap
Definitely true, but if we just classify "self-replicating molecules" as life,
they become just another coexisting organism in the mix of billions, perhaps
scavenging some form of energy that's unsuitable to larger forms. We've only
recently developed the ability to observe things at that scale, and it's still
a very fiddly process as I understand it, so the idea that there is
undiscovered molecule-scale life interacting with larger-scale life doesn't
seem too far-fetched to me.

The most interesting answer that I hope comes out of this research is how
sensitive the process is that leads to the creation of these molecules. If
it's robust and simple, we can expect to find life scattered all over the
universe. If it's extremely dependent on conditions found only in a narrow
window of time on Earth, the picture is probably much more lonely.

~~~
maxerickson
Yes, the semantics quickly starts to get in the way.

I suppose you can look at viruses as replicator molecules that have adapted to
a (relatively) cell heavy environment.

