The Origin of Life: Unsolved problem now shopped to off-market solutions?
|November 22, 2007||Posted by O'Leary under The Design of Life|
The origin of life is one of the great unsolved problems of science. Nobody knows how, where or when life originated. About all that is known for certain is that microbial life had established itself on Earth by about three and a half billion years ago. In the absence of hard evidence of what came before, there is plenty of scope for disagreement.
Yes indeed. Three decades ago, he notes, no one would have expected it to happen twice in the observable universe, because it was so unlikely:
That conservative position was exemplified by Nobel Prize–winning French biologist Jacques Monod, who wrote in 1970: “Man at last knows that he is alone in the unfeeling immensity of the universe, out of which he emerged only by chance.”
Yet researchers are now willing to entertain the very possibility St. Monod rejected. The mood has shifted in favour of a “cosmic imperative.”
That can only be because the effort to find a random origin of life is widely dismissed as unlikely.
Here are two facts: (1) We do not know how life could have arisen by chance here on Earth and (2) a chance origin is grossly improbable given the known age of the earth and the complexity of the machinery of cells.
So the default position, in Davies’s view, is to look for evidence that life somehow arises by chance everywhere IF conditions are right. That implies that there is a law of some sort, according to which life must arise. Fortunately, it may be possible to test his view, sort of.
Happily, he recognizes that. In the linked article, he argues that finding life on Mars would “decisively confirm” the view that “life is written into the laws of nature.” But, because (in his estimation) it may be a long time before studies of Mars yield any worthwhile information, researchers are currently looking for exotic life forms on Earth.
These endless forms most beautiful are – according to the prediction – so different from the common run of life that scientists will be forced to conclude that life was bound to arise on Earth as it is in Heaven somehow… according to a law that no one yet knows and perhaps no one can know.
He hopes to find life in the “distant past” or a “shadow biosphere.” Indeed, it is a “tantalizing possibility” that these alien life forms might have arisen independently:
The orthodox view of biogenesis holds that if life on Earth originated more than once, one form would have swiftly predominated and eliminated all the others. This extermination might have happened, for example, if one form quickly appropriated all the available resources or “ganged up” on a weaker form of life by swapping successful genes exclusively with its own kind. But this argument is weak. Bacteria and archaea, two very different types of microorganisms that descended from a common ancestor more than three billion years ago, have peacefully coexisted ever since, without one eliminating the other. Moreover, alternative forms of life might not have directly competed with known organisms, either because the aliens occupied extreme environments where familiar microbes could not survive or because the two forms of life required different resources.
Even if alternative life does not exist now, it might have flourished in the distant past before dying out for some reason. In that case, scientists might still be able to find markers of their extinct biology in the geologic record. If alternative life had a distinctively different metabolism, say, it might have altered rocks or created mineral deposits in a way that cannot be explained by the activities of known organisms.
These strike me as the explanations of a desperate man. I am not disputing them, I am only saying – not to empty the pub or anything – that I have heard similar arguments for leprechauns … And it pays to be cautious.
(EXTREME CAUTION: Whatever way life originated,, suggesting the possibility of a high-information or intelligent origin may constitute a violation of human rights in Europe.) If you are a resident of Europe, proceed with extreme caution when evaluating the fact base in this area. Ensure that you have a plausible explanation for even seeking information. If caught wondering, you might try pleading insanity or low IQ or use of legal recreational drugs. NEVER say that you doubt whatever official explanation is proferred to you, no matter how far-fetched or ridiculous. “Prison” is not a health food.
But now, for real people: The big news in recent years has not been serious stuff about how life originated (there isn’t any), but the willingness of scientists to entertain the view that it might have originated in ways that contradict long-held beliefs. In that respect, Davies is level with the pack:
Some of the lessons gleaned from the universal tree of life contradict long-held beliefs. For instance, the recognition of the deep evolutionary divergence between Archaea and Bacteria shattered the entrenched notion of evolutionary unity among procaryotes. The phylogenetic results also show that the eucaryotic nuclear line of descent, Eucarya, is as old as the procaryotic lines, Archaea and Bacteria. The idea that the eucaryotic cell arose relatively recently (1-1.5 billion years ago was a common assumption based on no credible data), from the fusion of two procaryotes, proved essentially incorrect. To be sure, the rRNA-based data confirm that mitochondria and chloroplasts are of endosymbiotic bacterial origin, as postulated long ago (note in the figure the association of the mitochondrial and chloroplast lineages with Bacteria). The organellar lineages emerge from subgroups of the Bacteria, however, so their evolution must have occurred relatively late in the history of life. Some microbial eucaryotic lineages seem never to have had mitochondria and chloroplasts so may have diverged from the eucaryotic line of descent prior to the incorporation of the organelles.
Davies makes the very interesting suggestion that – to find the life forms that support his view – we look for right-handed rather than left-handed chirality:
Large biological molecules possess a definite handedness: although the atoms in a molecule can be configured into two mirror-image orientations—left-handed or right-handed—molecules must possess compatible chirality to assemble into more complex structures. In known life-forms, the amino acids—the building blocks of proteins—are left-handed, whereas the sugars are right-handed and DNA is a right-handed double helix. The laws of chemistry, however, are blind to left and right, so if life started again from scratch, there would be a 50–50 chance that its building blocks would be molecules of the opposite handedness. Shadow life could in principle be biochemically almost identical to known life but made of mirror-image molecules. Such mirror life would not compete directly with known life, nor could the two forms swap genes, because the relevant molecules would not be interchangeable.
Shadow life? It looks to me like materialist atheism needs to generate the equivalent of the medieval “realms of faerie” in a modernist world, while using the stage machinery of current science.
Look I don’t care. If the right hand works, fine. If the left hand works, fine.
Presumably, you’d just have to duplicate everything that the left hand does onto the right hand. So then we have transposed all the BIG problems.
Like, Michelangelo was supposedly left-handed or something, and that EXPLAINS the Sistine Chapel.
If you live in Europe, consult your human rights advisor before forming an opinion about this post.