Genome complexity: most important article ever! (Introduction)

by David Turell @, Thursday, May 07, 2015, 15:01 (3249 days ago) @ David Turell

This is a must read with care and full understanding. It is a description of the inventive mechanism imbedded in gene networks. It describes patterns and suggests laws covering the drive to complexity that seems to be the force behind evolvability.-There are nuggets below, but it must be fully digested. It reeks of design, but the author can't say that. Darwinists would pounce.-http://nautil.us/issue/20/creativity/the-strange-inevitability-of-evolution-"Ah, but isn't all this wonder simply the product of the blind fumbling of Darwinian evolution, that mindless machine which takes random variation and sieves it by natural selection? Well, not quite. You don't have to be a benighted creationist, nor even a believer in divine providence, to argue that Darwin's astonishing theory doesn't fully explain why nature is so marvelously, endlessly inventive. “Darwin's theory surely is the most important intellectual achievement of his time, perhaps of all time,” says evolutionary biologist Andreas Wagner of the University of Zurich. “But the biggest mystery about evolution eluded his theory. And he couldn't even get close to solving it.”-"What Wagner is talking about is how evolution innovates: as he puts it, “how the living world creates.” Natural selection supplies an incredibly powerful way of pruning variation into effective solutions to the challenges of the environment. But it can't explain where all that variation came from. As the biologist Hugo de Vries wrote in 1905, “natural selection may explain the survival of the fittest, but it cannot explain the arrival of the fittest.” Over the past several years, Wagner and a handful of others have been starting to understand the origins of evolutionary innovation. Thanks to their findings so far, we can now see not only how Darwinian evolution works but why it works: what makes it possible.-***-"The trouble is that traits don't in general map so neatly onto genes: They arise from interactions between many genes that regulate one another's activity in complex networks, or “gene circuits.” No matter, you might think: Evolution has plenty of time, and it will find the “good” gene circuits eventually. But the math says otherwise.-***
"In all these cases the questions are the same, and point to, as Wagner puts it, a “dirty secret” behind the success of the so-called modern synthesis of Darwinian evolutionary theory and genetics. How does evolution find workable solutions when it lacks the means to explore even a small fraction of the options? And how does evolution find its way from an existing solution to a viable new one—how does it create? The answer is, at least in part, a simple one: It's easier than it looks. But only because the landscape that the evolutionary process explores has a remarkable structure, and one that neither Darwin nor his successors who merged Darwinism with genetics had anticipated.-***-"Yet the question that remains is: Why does the space of evolutionary options have this essential, robust structure? “We simply don't know why genotype networks are interwoven the way they are,” admits Wagner. Jesse Bloom of the Fred Hutchinson Cancer Research Center in Seattle, a specialist on protein evolution, suggests that perhaps that question is back to front: “One could posit that evolution is only able to work effectively if this property exists, and so the things that ended up evolving have this property,” he says. But he admits that this would be hard to prove.-***-"These ideas suggest that evolvability and openness to innovation are features not just of life but of information itself. That is a view long championed by Schuster's sometime collaborator, Nobel laureate chemist Manfred Eigen, who insists that Darwinian evolution is not merely the organizing principle of biology but a “law of physics,” an inevitable result of how information is organized in complex systems. And if that's right, it would seem that the appearance of life was not a fantastic fluke but almost a mathematical inevitability."


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