Logic and evolution: doubting Darwin; part 2 (Introduction)

by David Turell , Wednesday, May 15, 2019, 05:07 (2018 days ago) @ David Turell

We continue:

he odds against blind Darwinian chance having turned up even one mutation with the potential to push evolution forward are 1040x(1/1077)—1040 tries, where your odds of success each time are 1 in 1077—which equals 1 in 1037. In practical terms, those odds are still zero. Zero odds of producing a single promising mutation in the whole history of life. Darwin loses.

His idea is still perfectly reasonable in the abstract. But concretely, he is overwhelmed by numbers he couldn’t possibly have foreseen: the ridiculously large number of amino-acid chains relative to number of useful proteins. Those numbers transcend the details of any particular set of estimates. The obvious fact is that genes, in storing blueprints for the proteins that form the basis of cellular life, encode an awe-inspiring amount of information. You don’t turn up a useful protein merely by doodling on the back of an envelope, any more than you write a Mozart aria by assembling three sheets of staff paper and scattering notes around. Profound biochemical knowledge is somehow, in some sense, captured in every description of a working protein. Where on earth did it all come from?

Neo-Darwinianism says that nature simply rolls the dice, and if something useful emerges, great. Otherwise, try again. But useful sequences are so gigantically rare that this answer simply won’t work. Studies of the sort Meyer discusses show that Neo-Darwinism is the quintessence of a bad bet.

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To help create a brand new form of organism, a mutation must affect a gene that does its job early and controls the expression of other genes that come into play later on as the organism grows. But mutations to these early-acting “strategic” genes, which create the big body-plan changes required by macro-evolution, seem to be invariably fatal. They kill off the organism long before it can reproduce. This is common sense. Severely deformed creatures don’t ever seem fated to lead the way to glorious new forms of life. Instead, they die young.

Evidently there are a total of no examples in the literature of mutations that affect early development and the body plan as a whole and are not fatal. The German geneticists Christiane Nüsslein-Volhard and Eric Wieschaus won the Nobel Prize in 1995 for the “Heidelberg screen,” an exhaustive investigation of every observable or inducible mutation of Drosophila melanogaster (the same patient, long-suffering fruit fly I meddled with relentlessly in an undergraduate genetics lab in the 1970s). “[W]e think we’ve hit all the genes required to specify the body plan of Drosophila,” said Wieschaus in answering a question after a talk. Not one, he continued, is “promising as raw materials for macroevolution”—because mutations in them all killed off the fly long before it could mate. If an exhaustive search rules out every last plausible gene as a candidate for large-scale Drosophila evolution, where does that leave Darwin? Wieschaus continues: “What are—or what would be—the right mutations for major evolutionary change? And we don’t know the answer to that.”

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Research on animal development and macroevolution over the last thirty years—research done from within the neo-Darwinian framework—has shown that the neo-Darwinian explanation for the origin of new body plans is overwhelmingly likely to be false—and for reasons that Darwin himself would have understood.

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Darwin’s theory, after all, is an attempt to explain “design without a designer,” according to evolutionary biologist Francisco Ayala. An intelligent designer might seem more necessary than ever now that we understand so much cellular biology, and the impossibly long odds facing any attempt to design proteins by chance, or assemble the regulatory mechanisms that control the life cycle of a cell.

Meyer doesn’t reject Darwinian evolution. He only rejects it as a sufficient theory of life as we know it. He’s made a painstaking investigation of Darwin’s theory and has rejected it for many good reasons that he has carefully explained. He didn’t rush to embrace intelligent design. Just the opposite. But the explosion of detailed, precise information that was necessary to build the brand-new Cambrian organisms, and the fact that the information was encoded, represented symbolically, in DNA nucleotides, suggests to Meyer that an intelligent designer must have been responsible. “Our uniform experience of cause and effect shows that intelligent design is the only known cause of the origin of large amounts of functionally specified digital information,” he writes.

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Although Stephen Meyer’s book is a landmark in the intellectual history of Darwinism, the theory will be with us for a long time, exerting enormous cultural force. Darwin is no Newton. Newton’s physics survived Einstein and will always survive, because it explains the cases that dominate all of space-time except for the extreme ends of the spectrum, at the very smallest and largest scales. It’s just these most important cases, the ones we see all around us, that Darwin cannot explain. Yet his theory does explain cases of real significance. And Darwin’s intellectual daring will always be inspiring. The man will always be admired.

Comment: Gelernter is an atheist and the famed author of "The closing of the American Mind"