I was sort of replying to the premise of the first poster that "DNA and microbes can travel on asteroids for millions of years." In this situation if the DNA/microbe is to be stable enough to survive in an information viable form for long enough to drift between stars then it would probably be too cold to go through the vast numbers of reactions required for exogenesis. I would concede that a comet cycling round its star every 100 years for a billion years might possibly provide a suitable reaction vessel, but then this isn't really panspermia as it would be localised to a rather small corner of the Universe.
I'm quite happy with the contents of the Sigma catalogue raining down from space as a kick start for the generation of life on earth though. But from there to self-perpetuating life forms seems to be really mostly theory at the moment.
Zeb
I'm quite happy with the contents of the Sigma catalogue raining down from space as a kick start for the generation of life on earth though. But from there to self-perpetuating life forms seems to be really mostly theory at the moment.
Zeb
> Date: Tue, 22 May 2012 16:25:07 +0100
> From: cathalgarvey@gmail.com
> To: diybio@googlegroups.com
> Subject: Re: [DIYbio] Information physics and theoretical limits of extremely old DNA?
>
>
> > Does leave the little problem of where life
> > came from in the first place...
>
> No it doesn't. We have great experiments going back decades showing how
> easy it is for complex chemistry to emerge from early earth conditions,
> and from there chaos theory takes over; self-replicating patterns will
> emerge and, by their very nature, self-perpetuate until they dominate
> chemistry in the environment.
>
> Next thing you know, the pool of available randomness to convert runs
> out; suddenly your self-perpetuating patterns are eating one another,
> and evolution begins. Somewhere from here, you get what we might define
> as life, but it's a very fuzzy boundary.
>
> Early (and present) Earth has all you need; steep energy gradients, lots
> of tasty elemental and molecular precursors, and enough solvent to make
> it all happen in the same container.
>
> While exobiologists love the idea of life being seeded from a
> space-missile, there's really no need for an asteroid/comet/other to
> explain life on earth. We already know how it can happen without space
> missiles, and it's more than plausible.
>
> > Re ancient DNA I wonder whether anyone has looked in crude
> > oil for non-bacterial DNA/protein sequences. I know you can find
> > things like porphryin in there but I guess it might be too non-polar
> > for DNA, you might find some lipophilic pepdites though.
>
> Oil and other fossil fuels aren't old enough for "early life" fossils,
> AFAIK. But you'll find plenty of non-bacterial DNA there; archaea, at
> the very least!
>
> --
> www.indiebiotech.com
> twitter.com/onetruecathal
> joindiaspora.com/u/cathalgarvey
> PGP Public Key: http://bit.ly/CathalGKey
>
> --
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> From: cathalgarvey@gmail.com
> To: diybio@googlegroups.com
> Subject: Re: [DIYbio] Information physics and theoretical limits of extremely old DNA?
>
>
> > Does leave the little problem of where life
> > came from in the first place...
>
> No it doesn't. We have great experiments going back decades showing how
> easy it is for complex chemistry to emerge from early earth conditions,
> and from there chaos theory takes over; self-replicating patterns will
> emerge and, by their very nature, self-perpetuate until they dominate
> chemistry in the environment.
>
> Next thing you know, the pool of available randomness to convert runs
> out; suddenly your self-perpetuating patterns are eating one another,
> and evolution begins. Somewhere from here, you get what we might define
> as life, but it's a very fuzzy boundary.
>
> Early (and present) Earth has all you need; steep energy gradients, lots
> of tasty elemental and molecular precursors, and enough solvent to make
> it all happen in the same container.
>
> While exobiologists love the idea of life being seeded from a
> space-missile, there's really no need for an asteroid/comet/other to
> explain life on earth. We already know how it can happen without space
> missiles, and it's more than plausible.
>
> > Re ancient DNA I wonder whether anyone has looked in crude
> > oil for non-bacterial DNA/protein sequences. I know you can find
> > things like porphryin in there but I guess it might be too non-polar
> > for DNA, you might find some lipophilic pepdites though.
>
> Oil and other fossil fuels aren't old enough for "early life" fossils,
> AFAIK. But you'll find plenty of non-bacterial DNA there; archaea, at
> the very least!
>
> --
> www.indiebiotech.com
> twitter.com/onetruecathal
> joindiaspora.com/u/cathalgarvey
> PGP Public Key: http://bit.ly/CathalGKey
>
> --
> You received this message because you are subscribed to the Google Groups "DIYbio" group.
> To post to this group, send email to diybio@googlegroups.com.
> To unsubscribe from this group, send email to diybio+unsubscribe@googlegroups.com.
> For more options, visit this group at http://groups.google.com/group/diybio?hl=en.
>
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