17 February 2007

Open Source Life?

A chap named Robert Shapiro has a number of interesting things to say about the origins of life, including that an Open Sourcey-looking beginning is far more likely than any of the traditional approaches.

For example, he completely trashes the Miller-&-Urey experiment as a means for producing DNA or RNA, then goes on to point out that an RNA-based origin is “the prebiotic chemist’s nightmare’.

After spending a few pages totally wiping the floor with these traditional methods, Shapiro then proposes assembly of smaller molecules. He’s got quite a few impressive qualification to do this from.

His diatribe against RNA is pretty amusing:

The analogy that comes to mind is that of a golfer, who having played a golf ball through an 18-hole course, then assumed that the ball could also play itself around the course in his absence. He had demonstrated the possibility of the event; it was only necessary to presume that some combination of natural forces (earthquakes, winds, tornadoes and floods, for example) could produce the same result, given enough time. No physical law need be broken for spontaneous RNA formation to happen, but the chances against it are so immense, that the suggestion implies that the non-living world had an innate desire to generate RNA. The majority of origin-of-life scientists who still support the RNA-first theory either accept this concept (implicitly, if not explicitly) or feel that the immensely unfavorable odds were simply overcome by good luck.

So... it seems that if anywhere, naturalistic life first appeared on a cold, rocky version of SourgeForge, no?

5 comments:

TimC said...

Am I right in that he objects to RNA being produced by chance as the first thing leading to life? His objection sounds somewhat similar to the objection creationists (and in particularly, intelligent designists) lodge against evolution -- so much chance, so little time.

Sure, there is an infintesimally small, but non zero chance, of a random set of events leading to the production of the RNA/DNA sequeunce. So small as to not appear in the vast majority of earths in the vast majority of universes in 13 billion years. *However*, the chance of leading to *any* self-reproducing set of molecules is the above infintesimal chance, multiplied by however number of combinations of self-reproducing molecules you could come up with. A much larger number -- and funnily enough, a number giving a good chance that such a system will come about after a billion or so years of lightning and prehistoric chemical reactions. The guy who came up with intelligent design describes himself as a mathematician, but he neglected year 11 combinatorics -- not the sign of anyone competant in the field.

Major said...

To put it in even simpler (primary school) maths, they correctly find a great big number in the denominator and incorrectly assume a one in the numerator rather than the actual, much larger, number.

Leon Brooks said...

Well... half marks each.

Major's right about the denominator, and half-right about the numerator. There are many factors working to make the numerator smaller. If you simply tot the numbers up, they look pretty interesting.

However, factor in a bit of (please excuse the metaphor but I couldn’t resist) real life (like the distances between molecules in real situations) & the odds start looking mundane again.

There has to be a factor or few missing in there if a couple of billion years’ worth of lightning are going to have a positive (for life) result.

Assuming that we know all the factors is not going to be productive, & neither is invoking a magic wand to solve your problems with.

IDers need more justice for their wands, & gradualists need much better factors to stitch their components together much faster than anything seen so far, & keep them together.

My personal bet is that both sides have something significant to learn. There’s room for at least a 3rd team in this game.

Major said...

... and then multiply by infinity for number of possible universes.

Leon Brooks said...

major: Er... possibly multiply by possibly infinity for an infinite number of different universes — presuming that theories about such are right — then happen to pick the correct one to monitor.

Hmmm.

Doesn't sound like a safe way to earn a living. (-:

Other than that, good point.

I guess we stay tuned to the multiple-universes theorists for a few more years & see if they come up with some backup evidence. Science can be more fun than a rack of poker machines, some days. (-: