Continuity and discontinuity

Here’s an interesting podcast by Intelligent Design proponent Paul Nelson, a philosopher of science, whom I’ve got to know a little both through Peaceful Science and via a mutual friend.

I’ve always been committed to God as Creator (through his Logos, the Son), but have become increasingly agnostic about his means of creation the more I’ve studied it, particularly over the last rather intense decade. There’s a mass of my material on The Hump on my interactions with the science, philosophy, history and sociology, not to mention the theology, so I won’t try to summarise it here.

But the net result is that Paul’s questioning of the principle of universal common descent is intriguing, rather than triggering, to me. Raised hackles hinder learning, I find. He begins with the assumption he was taught at university that the DNA code itself is so fundamental that it is universal, and could not evolve further. It was also accepted then, in the ’80s, that the code could not have itself evolved, so that the best explanation was “a frozen accident.”

Nelson points out how, since then, so many variations of the code have been found that the question of its evolution simply has to be tackled. He adds other examples of core cellular functions, such as ribsomal enzyme activities, being managed by entirely different proteins in different biological groups, and suggests that in the last decade an increasing number of biologists have been coming round to rejecting UCD in favour of multiple origins of life.

Now this is not in itself a problem. Even Darwin traced the origin of life back to “one, or a few” original forms. To insist on a single origin on principle, in the absence of any coherent theory of how life first occurred, is simply dogma. It’s hard to see why any scientist would make an issue of it.

But there are a few serious problems with this conclusion, the first of which is that many of these discontinuities in basic molecular function show every sign of having been acquired during later biological history, rather than maintained intact in primordial lines. For example, Nelson cites advanced ciliates like Paramecium, which possess an alternative stop codon in an otherwise canonical code. As far as I know, nobody suggests that this group formed a separate evolutionary line right back to a separate origin of life. Nelson also mentions, though does not elaborate in this podcast, the increasing knowledge of just how many unique “orfan” genes there are in all species genomes so far sequenced.

Back in 2017 I quoted an article by Eugene Koonin on the evolution of DNA, in which he examines three current theories of DNA evolution, considers them to be inadequate, and concludes that the “frozen accident” hypothesis remains the best explanation. “Rare stuff happens, so get over it” seems to be his motto, and in an earlier article he actually invoked a multiverse to reduce the odds of the DNA code forming.

In my own article, I quoted Perry Marshall’s words on this:

“There’s only one problem with that approach: It’s not science.”

Quite so: I’m reminded of the schizophrenic whose doctor tried to persuade him he was not dead by getting him to admit that dead men don’t bleed, and then pricking his finger with a pin. “Wow!” said the patient. “So dead men do bleed!”

The issue is that all plausible “naturalistic” scientific explanations of complex procesesses (“naturalistic” meaning, if it means anything at all, “ateleological”) depend on chance variations though gradual stages. Natura non facit saltus. For this reason few of these explanations remain plausible apart from some theory of natural selection, and that has lost traction in modern evolutionary theory, and never had much anyway in origin of life studies.

So although it would be reasonable to say that, if the origin of life is “natural,” one would expect it to arise separately multiple times (and to be widespread through the universe), that line of thought becomes less credible when considering just how many of the processes in all these various forms of life are near-identical, whilst a few as basic as the DNA code are significantly different. The supposed natural continuity of a gradual process is shown to contain major discontinuities – even, perhaps, discrepancies.

Multiple origins is a problem when viewed from the other end as well. If life is so easy to form that it can happen multiple times, and using variable processes, then how come it hasn’t been possible to even begin to achieve it under controlled laboratory conditions? To some extent, the inability to produce life artificially depends on its being a unique and fortuitous – and therefore not natural and gradual – event.

If, alternatively, one posits a single fortuitous origin of life, and the evolution of a single DNA code and the other significant variants pointed out by Paul Nelson, then one faces a separate problem of discontinuity, as discussed in Koonin’s article. There is no very plausible way for such things as the DNA code to evolved once fixed, which is why so many have embraced the explanation of multiple origins. It’s a Catch 22 situation.

In fact, discontinuities are rampant even at the basic level of phylogeny. Cladistics depends on finding the best fit, seldom meaning unambiguous continuity, but rather the smallest number of anomalies. And whether one is studying morphology or genomes, surprising convergences, sophisticated abilities like sight or echolocation evolving multiple times, and complete revision of seemingly obvious family relationships abound.

Here’s a rather ID conclusion: naturalism requires gradualism, and where discontinuities that exclude gradual processes are found, the only naturalistic recourses are either to place a great deal of faith in Epicurean chance – hopeful monsters – or to reintroduce a scientifically baseless teleology as mystical as Platonism.

Perhaps the form of DNA exists somewhere out there in the laws of nature, and matter is magnetically, though seldom perfectly, attracted to it. One then, of course, has to account for the existence of the Platonic forms. Not many people follow that path.

The only alternative is God, and although, as so many point out, God’s purposes and processes are not our purposes and processes, it is true to say that beings who make creative choices have both continuity and discontinuity equally at their disposal. ID people may point out that the logical evolution of, say, motor cars over the years actually occurs by conscious design choices based on greater knowledge, changing needs or simply fashion. Though the Christian God neither learns by experience nor follows fashion trends, he might well have his own reasons for employing laws of form such as bauplans and changing them gradually, and even for instantiating them by common descent rather than by instantaneous fiat.

A more interesting sign of choice, though, is the case of the discontinuous in otherwise regularly developed design: the decision to set up a Fender Stratocaster body with Gibson pickups and circuitry, or the conversion of a DeLorean to a time machine. Still life paintings follow a clear tradition. But artists like Salvador Dali can, at any time, choose to buck the tradition.

Discontinuities are immensely important in nature. Either they must be explained by Epicurean chance, or by the living God’s choice. Which you favour, however, depends entirely on choice.

Salvador Dali – Living Still Life (1956)

Jon Garvey

About Jon Garvey

Training in medicine (which was my career), social psychology and theology. Interests in most things, but especially the science-faith interface. The rest of my time, though, is spent writing, playing and recording music.
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