Prebiotic Soup--Revisiting the Miller Experiment [biogenesis]

Science Magazine ^ | May 2003 | Jeffrey L. Bada and Antonio Lazcano

[Loc123]

Yeah, this is monstorously out of date.

The newest theories that have been conjured up deal with self-catalyzing RNA. But there's a problem--this RNA is way to advanced and way to irreducible to have been present before even advanced biological organisms. And that RNA only folds minute times and doesn't push forward reactions, etc.

What that science article doesn't mention--and anyone can reference this by the sparse stories of abiotic orgins--is how increasingly unlikely abiogenesis appears to be on this planet.

I love it: now the prevailing theory is that life came from meteorites--and somehow the planet that spawned that life not only had more favorable conditions than Earth but also had achiral (L) organic molecules. It all comes down to faith for abiogenesis. Pass the buck.

This is not to say that someday we will never be able to synthesize life, however.

[Ogmios]

Oh, and what a difference, Placemarker

[Virginia-American]

I believe that if they run experiments that closely resemble what the smokestacks at the ocean floors are like, they might come up with some better luck.

I was thinking along the same lines. The Urey-Miller apparatus with a lot of different minerals, some submerged, some at the water-atmosphere boundary.

[DannyTN]

"What about the chemistry of 'black smokers' and geothermal vents in the deep oceans? "

It's going to take a lot of tap dancing to get me to believe DNA spontaneously came together. Black Smokers not withstanding.

[donh]

I love it: now the prevailing theory is that life came from meteorites

The prevailing theory is that life happened on the mudball you are standing on.

[donh]

It's going to take a lot of tap dancing to get me to believe DNA spontaneously came together.

Good thing that's not on the agenda, then. All contemporary theories of any passing scientific gravity hold that life evolved gradually, from it's beginnings through the present moment.

[DannyTN]

"All contemporary theories of any passing scientific gravity hold that life evolved gradually, from it's beginnings through the present moment. "

Somebody certainly passed that theory.

[Ogmios]

Well, you have to work with what you've got and work backwards.

You can't start right from the beginning and hope you get it right, you have to start where you are and move back.

We're here, so scientifically we have to assume that life came together here as well, therefore, we move back until we get stuck, then we figure that out and keep going until we get stuck again and so on and so forth.

Right now, we are looking at a number of different hypothesis regarding the beginnings of life, the smokestacks at this point give us some of the most promising elements that we need to give us an actual starting point.

But the fact is that we can't start from the beginning, we have to start from the now and work our way back to the then.

[Ogmios]

I think the pressure, the temperature etc, can create some very complicated structures, and I think that it is what holds the most promise. The minerals are there, a very regular and unchanging environment are there, etc.

I think that in order for life to start, it had to have a very stable environment, and I think the smokers are it. Their environment is about as stable as you can wish for, then as evolution kicked in, the stability of the organisms themselves changed as they moved farther and farther from the stable environment in which they were born.

Excess energy has a strange way of turning elements into more complex elements, mixing and combining in certain ways etc, and the environment certainly seems right for the pressure, temperature, stability, and most of all the elements themselves to slowly turn more complex.

[donh]

Somebody certainly passed that theory.

Creationists keep trying to pass off spontaneous abiogensis of cellular DNA-based life as a scientific theory so they can have something to refute with technical sounding bogus statistical calculations.

[Virginia-American]

I wonder if there are the equivalent of smokers under the ice of Europa and other Jovian moons. They're heated internally by tidal stresses.

[DannyTN]

Whether it's pondscum happens slowly or pondscum happens quickly. It's still "Pondscum happens"

[Ogmios]

Actually, I wouldn't doubt it, and exobiology is fast becoming the next big biological profession.

A lifeform that would live near such a smoker needs nothing more then the heat and output of the smokers, and of course if it is near the top of the foodchain it's smokestack neighbors. Jupiter itself and the tidal stresses that it puts on it's satelites would really be all the energy necassaary to create the situation.

I would love to send a probe to Europa and dig in and see if theres liquid under there, the cracking etc makes it seem likely, and if possible to dive into that ocean and see if there are simple or even possibly more advanced lifeforms under the ice.

[jennyp]

It's going to take a lot of tap dancing to get me to believe DNA spontaneously came together. Black Smokers not withstanding.

DNA came much later. RNA (or possibly a simpler RNA analogue) came first.

The process of abiogenesis had many steps that must be explained, and these holes in our knowledge are slowly (but surely) being filled. So those of us who are unafraid of the science see each new discovery & say, "fascinating, good work!" While you who are afraid of us finding how life got started get another chance to say "yeah but look at all the problems that remain over here!"

Interesting how one side of the debate always ends up cheering each new discovery or intriguing theory, while the other side always gets nervous at new discoveries.

[donh]

So does NASA, Callisto is the other moon that seems like a prominent candidate.

http://www.resa.net/nasa/europa_life.htm

[donh]

Whether it's pondscum happens slowly or pondscum happens quickly. It's still "Pondscum happens"

Indeed. And in like manner, so do creatures like oysters, otters, and orangutangs happen, in the long, slow march toward humans.

[DannyTN]

"Well, you have to work with what you've got "

And even when you've got nothing, their's always imagination.

[Ogmios]

That's probably where I got that idea then, Callisto? Hadn't heard about that one.

The next 10 years or so are going to be very exciting.

Who needs Extraterrestrials, when there might be other life within our own Solar System, and then what happens to the chances of finding more life outside the Solar system if indeed the moons of jupiter hold their own lifeforms?

Oh yes, very exciting..

[Ogmios]

Science never works from nothing, I have no idea where you get this from.

Science comes up with a hypothesis, and then tests it and tests it.

That's what all of these abiogenesis hypothesis are all about, we come up with plausible scenarios, and then see if there is anything to them, when they check out, make predictions, help us study other phenomonon, then they become theories.

None of us are sold on any particular hypothesis regarding Abiogenesis, but it sure is fun to contemplate and kick around.

[BiffWondercat]

Well timed pic!

I just find it facinating to have such a biosphere in such adverse conditions. I would think that the protiens organized before DNA/RNA started getting into the business.