The god of the gaffes 17

Why would baffled scientists reach for a supernatural explanation of puzzling phenomena?

David Gelernter, professor of computer science at Yale, reviews books that argue against Charles Darwin at the Claremont Review of Books in an article titled Giving Up Darwin.

Stephen Meyer’s thoughtful and meticulous Darwin’s Doubt (2013) convinced me that Darwin has failed. … Two other books are also essential: The Deniable Darwin and Other Essays (2009), by David Berlinski, and Debating Darwin’s Doubt (2015), an anthology edited by David Klinghoffer, which collects some of the arguments Meyer’s book stirred up. These three form a fateful battle group that most people would rather ignore. Bringing to bear the work of many dozen scientists over many decades, Meyer, who after a stint as a geophysicist in Dallas earned a Ph.D. in History and Philosophy of Science from Cambridge and now directs the Discovery Institute’s Center for Science and Culture, disassembles the theory of evolution piece by piece. Darwin’s Doubt is one of the most important books in a generation. Few open-minded people will finish it with their faith in Darwin intact.

Gelernter explains the anti-Darwin arguments:

In the famous “Cambrian explosion” of around half a billion years ago, a striking variety of new organisms—including the first-ever animals—pop up suddenly in the fossil record over a mere 70-odd million years. This great outburst followed many hundreds of millions of years of slow growth and scanty fossils, mainly of single-celled organisms, dating back to the origins of life roughly three and half billion years ago.

Darwin’s theory predicts that new life forms evolve gradually from old ones in a constantly branching, spreading tree of life. Those brave new Cambrian creatures must therefore have had Precambrian predecessors, similar but not quite as fancy and sophisticated. They could not have all blown out suddenly [if, he is saying, Darwin was right], like a bunch of geysers. Each must have had a closely related predecessor, which must have had its own predecessors: Darwinian evolution is gradual, step-by-step. All those predecessors must have come together, further back, into a series of branches leading down to the (long ago) trunk.

But those predecessors of the Cambrian creatures are missing. Darwin himself was disturbed by their absence from the fossil record. He believed they would turn up eventually. Some of his contemporaries … held that the fossil record was clear enough already, and showed that Darwin’s theory was wrong. Perhaps only a few sites had been searched for fossils, but they had been searched straight down. The Cambrian explosion had been unearthed, and beneath those Cambrian creatures their Precambrian predecessors should have been waiting—and weren’t. In fact, the fossil record as a whole lacked the upward-branching structure Darwin predicted.

The trunk was supposed to branch into many different species, each species giving rise to many genera, and towards the top of the tree you would find so much diversity that you could distinguish separate phyla—the large divisions (sponges, mosses, mollusks, chordates, and so on) that comprise the kingdoms of animals, plants, and several others … But … the fossil record shows the opposite: “representatives of separate phyla appearing first followed by lower-level diversification on those basic themes”. In general, “most species enter the evolutionary order fully formed and then depart unchanged”. The incremental development of new species is largely not there. Those missing pre-Cambrian organisms have still not turned up. (Although fossils are subject to interpretation, and some biologists place pre-Cambrian life-forms closer than others to the new-fangled Cambrian creatures.)

Some researchers have guessed that those missing Precambrian precursors were too small or too soft-bodied to have made good fossils. Meyer notes that fossil traces of ancient bacteria and single-celled algae have been discovered: smallness per se doesn’t mean that an organism can’t leave fossil traces—although the existence of fossils depends on the surroundings in which the organism lived, and the history of the relevant rock during the ages since it died. The story is similar for soft-bodied organisms. Hard-bodied forms are more likely to be fossilized than soft-bodied ones, but many fossils of soft-bodied organisms and body parts do exist. Precambrian fossil deposits have been discovered in which tiny, soft-bodied embryo sponges are preserved—but no predecessors to the celebrity organisms of the Cambrian explosion.

This sort of negative evidence can’t ever be conclusive. But the ever-expanding fossil archives don’t look good for Darwin, who made clear and concrete predictions that have (so far) been falsified—according to many reputable paleontologists, anyway. When does the clock run out on those predictions? Never. But any thoughtful person must ask himself whether scientists today are looking for evidence that bears on Darwin, or looking to explain away evidence that contradicts him. There are some of each. Scientists are only human, and their thinking (like everyone else’s) is colored by emotion.

Darwin’s main problem, however, is molecular biology. There was no such thing in his own time. We now see from inside what he could only see from outside, as if he had developed a theory of mobile phone evolution without knowing that there were computers and software inside or what the digital revolution was all about. Under the circumstances, he did brilliantly.

Biology in his time was for naturalists, not laboratory scientists. … But the character of the field has changed, and it’s not surprising that old theories don’t necessarily still work.

Darwin’s theory is simple to grasp; its simplicity is the heart of its brilliance and power. We all know that variation occurs naturally among individuals of the same type—white or black sheep, dove-gray versus off-white or pale beige pigeons … [M]any variations have no effect on a creature’s prospects, but some do. A sheep born with extra-warm wool will presumably do better at surviving a rough Scottish winter than his normal-wooled friends. Such a sheep would be more likely than normal sheep to live long enough to mate, and pass on its superior trait to the next generation. Over millions of years, small good-for-survival variations accumulate, and eventually (says Darwin) you have a brand new species. The same mechanism naturally favors genes that are right for the local environment—warm wool in Scotland, light and comfortable wool for the tropics, other varieties for mountains and deserts. Thus one species (your standard sheep) might eventually become four specialized ones. And thus new species should develop from old in the upward-branching tree pattern Darwin described.

The advent of molecular biology made it possible to transform Darwinism into Neo-Darwinism. The new version explains (it doesn’t merely cite) natural variation, as the consequence of random change or mutation to the genetic information within cells that deal with reproduction. Those cells can pass genetic change onward to the next generation, thus changing—potentially—the future of the species and not just one individual’s career.

The engine that powers Neo-Darwinian evolution is pure chance and lots of time. By filling in the details of cellular life, molecular biology makes it possible to estimate the power of that simple mechanism. But what does generating new forms of life entail? Many biologists agree that generating a new shape of protein is the essence of it. Only if Neo-Darwinian evolution is creative enough to do that is it capable of creating new life-forms and pushing evolution forward.

Proteins are the special ops forces (or maybe the Marines) of living cells, except that they are common instead of rare; they do all the heavy lifting, all the tricky and critical assignments, in a dazzling range of roles. Proteins called enzymes catalyze all sorts of reactions and drive cellular metabolism. Other proteins (such as collagen) give cells shape and structure, like tent poles but in far more shapes. Nerve function, muscle function, and photosynthesis are all driven by proteins. And in doing these jobs and many others, the actual, 3-D shape of the protein molecule is important.

So, is the simple neo-Darwinian mechanism up to this task? Are random mutation plus natural selection sufficient to create new protein shapes?

Gelernter’s answer, in agreement with the books he is reviewing, is No. He explains why in some detail. We have no quarrel with him over this point. We are not scientists and have no idea whether the answer is solidly proved or not. We accept that the answer is No, and that, consequently, Darwin has been caught out and disproved – in part.

But the reviewed books are about giving up Darwin; negating evolution.

It can hardly be surprising that the revolution in biological knowledge over the last half-century should call for a new understanding of the origin of species.

A new understanding. Darwin was wrong. Evolution is wrong. Species do not evolve. So what does explain the existence of species?

We held our breath at this point in the article. A new theory, as exciting and revolutionary as was Darwin’s when it was sprung upon the world, but better in that it explains the phenomena which Darwin failed to explain, was about to be set before us.

You may be as disappointed as we were with the answer. What explains the “sudden explosion” of Cambrian species; how did all those new living things appear over “a mere 70-odd million years”?

Why, God put them there.

That’s it. Let your heart sink. It’s God again. Not that the word “God” emerges from the scientist’s lips or pen. No, no! In fact Professor Gelernter is careful to inform us that “religion” is not mentioned by the scientists whose work he is discussing.

What they offer us, is the uncertain semi-rationalist’s euphemism for God: “INTELLIGENT DESIGN”.

Intelligent Design, as Meyer describes it, is a simple and direct response to a specific event, the Cambrian explosion. The theory suggests that an intelligent cause intervened to create this extraordinary outburst. By “intelligent” Meyer understands “conscious”; the theory suggests nothing more about the designer.

Can  a “conscious” mind be understood to be anything but a human-type mind? So a human-type mind designed – and made – living things on this earth at least once “over a period of 70-odd million years”.

Gelernter reveals that he himself does not find Meyer’s answer satisfactory:

But where is the evidence? To Meyer and other proponents, that is like asking—after you have come across a tree that is split vertically down the center and half burnt up—“but where is the evidence of a lightning strike?” The exceptional intricacy of living things, and their elaborate mechanisms for fitting precisely into their natural surroundings, seemed to cry out for an intelligent designer long before molecular biology and biochemistry. …  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. …

 “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,” [Mayer]  writes. …

Known? Who knows “intelligent design” to be that cause?

If Meyer were invoking a single intervention by an intelligent designer at the invention of life, or of consciousness, or rationality, or self-aware consciousness, the idea might seem more natural. But then we still haven’t explained the Cambrian explosion. An intelligent designer who interferes repeatedly, on the other hand, poses an even harder problem of explaining why he chose to act when he did. Such a cause would necessarily have some sense of the big picture of life on earth. What was his strategy? How did he manage to back himself into so many corners, wasting energy on so many doomed organisms? Granted, they might each have contributed genes to our common stockpile—but could hardly have done so in the most efficient way. What was his purpose? And why did he do such an awfully slipshod job? Why are we so disease prone, heartbreak prone, and so on? An intelligent designer makes perfect sense in the abstract. The real challenge is how to fit this designer into life as we know it. Intelligent design might well be the ultimate answer. But as a theory, it would seem to have a long way to go.

To design is to purpose. The believers in the Intelligent Designer must be asked: What was his purpose? Why did the Designer design and make the life-forms?

And how intelligent was he when he made so many mistakes; made so many life-forms so badly that they could not survive?

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. …

We know that evolution happens. It is happening about us all the time. We ourselves evolve. If there are important questions about the evolution of species that remain unanswered, why not say, “Just as we now see from inside what Darwin could only see from outside, as if he had developed a theory of mobile phone evolution without knowing that there were computers and software inside or what the digital revolution was all about, so in the future we might learn what made the Cambrian explosion possible without looking to the supernatural to explain it.”

An Intelligent Designer is surely the least plausible, the most absurd “explanation” for how things are and how they came about. There is always the possibility that natural explanations will be found for natural phenomena however perplexing. There is no possibility that we will find anything outside of nature.

Posted under Philosophy, Science, Theology by Jillian Becker on Saturday, May 11, 2019

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