on 12 July 2013
If you have an inquisitive mind, you will probably have noticed you learnt as much--if not more--about a topic by examining what its critics had to say, and not only its supporters. And you will doubtless have had occasion to either become agnostic, or to adopt a contrary position to what may be portrayed as orthodoxy.
What Meyer's book is *not* about is pushing religion. In the first two parts, and the first two chapters of the third (16 of 20 chapters in all), he looks at the orthodox view of evolution, which he reports accurately. I speak as someone with a degree in zoology and a little research experience in the subject; so whilst I don't claim to be an expert, I know enough to know he's not distorting anything. At the same time, his aim is to show that orthodoxy does not explain the evidence of the fossil record with respect to the Cambrian period, nor how so many new body plans could have arisen in such a comparatively short time, with no readily identifiable pre-Cambrian precursors.
He's not alone in this view, even amongst non-ID-supporting scientists. In fact, in Chapters 15 and 16, he examines alternatives to standard neo-Darwinism (or the New Synthesis if you prefer) being put forward by them as we speak. And generally, throughout the book, you will find copious references to the literature, as well as amplifying footnotes at the end of the book. Check out the references; chase up the bios of the chemists, biochemists, geneticists, paleontologists, geologists, etc. who in various ways and degrees challenge an orthodoxy that is frequently put across to the public as completely settled, completely unquestionable truth. I've done quite a lot of such checking, and I can report that many of them are hardly great fans of ID.
It's a fascinating read, and I hope that open-minded people will welcome a single tome that tells them so much about orthodox views, and at the same time offers evidence why the explanatory power of those might be open to question. It's evidence I personally find persuasive, whilst I accept others might not; but even so, if one has an open mind, it should be found engaging. All the more so if one isn't overly familiar with the subject of evolution: because it covers a great deal of ground in a pretty accessible way. It's quite an education, and I'm speaking as a trained and qualified (recently retired) educator. I learnt an appreciable amount that I didn't already know, and it clarified my understanding on a number of specific scientific points.
If you don't want to read about ID, fair enough: simply ignore the last 4 chapters, which is the only place he explicitly deals with it. He thinks ID explains what neo-Darwinism, and those other competing, but non-ID theories I alluded to earlier, can't. He may be right or wrong about that, but that has no bearing on the previous 16 chapters where he's demonstrated the severe shortcomings of neo-Darwinism in explaining the Cambrian explosion, during which the majority of phyletic body plans still extant today seem to have arisen: something that is absolutely contrary to orthodoxy, where body plans should have gradually appeared through time.
We should find evidence for a single tree of life (with an ultimate single ancestor in the first single-celled life form on earth, appearing maybe 3.8 billion years ago, well before the Cambrian began around 500 mya). However, what we actually find in the case of animals is what appears to be an "orchard", with separate animal lineages diversifying ever since the Cambrian. Top-down rather than bottom up: complex plans appearing early, not late.
It's true that there were a few body plans of multicellular organisms extant before the Cambrian in the pre-Cambrian (including the extinct Ediacaran fauna), and that one of those, that of the sponges, still persists to this day. But one can find nothing in the pre-Cambrian that is an obvious precursor of trilobites (early arthropods) or any of the other new body plans that emerged in the Cambrian (around 20 of them, still around today, including the Chordates to which humans belong--amongst a total of around 25-35 depending on the classificatory system applied).
It stretches credulity beyond breaking point to postulate that precursors in the pre-Cambrian were soft-bodied and hence not fossilised, when in fact soft-tissue preservation in both the pre-Cambrian and Cambrian is readily demonstrable. It stretches credulity to think that we haven't yet found precursors but one day will, when statistical analysis of the fossil record shows it's extremely unlikely we would have missed *all* such evidence.
The new Cambrian body plans must have come from somewhere, unless your idea is of an intelligence that can magic up something from nothing, but Meyer doesn't deny the possibility of common descent, and certainly not the reality of evolution in the sense of change over time. He fully accepts that the earth is billions of years old, and, one might wrily argue, that the fossil record means what it actually says: that neo-Darwinian gradualism doesn't occur at the macro-evolutionary level (e.g. the formation of new body plans), even if it might occur at the micro-evolutionary level (e.g. low-level species divergence within a genus). He doesn't even deny that random mutation and natural selection have a role to play at the micro-evolutionary level.
Meyer gives a very good introduction to the concept of Shannon information and how that contrasts with functional, or specified, information. Put simply, any random combination of, say, fifty alphabetic characters is as likely, and contains as much information, as any other. But only a very few would spell out a recognisable English sentence. Vanishingly few from the 26^50 (approx. 5.6 x 10^70) combinations would do so. The issue is enormously amplified when one considers a modest protein containing 150 amino acids, for which any of 20^150 (approx. 1.4 x 10^195) combinations are possible, but for which a vanishingly small proportion have been demonstrated to be likely to be of functional use to organisms.
Neo-Darwinists will insist that it isn't only random mutation that is involved in evolution, but crucially, natural selection. But before the latter can select for a mutation, it has to have occurred, and most mutations are likely to be harmful than beneficial. The problem gets even worse when it is realised that innovations may require a number of proteins to act in a coordinated fashion. These are the kinds of facts that are addressed in "post-Darwinistic", non-ID theories (such as evo-devo and self-organisation, neo-Lamarckism, neutral theories and natural genetic engineering) discussed in chapters 14 and 15, and I have to agree with Meyer, they aren't convincing either.
If there's one key theme throughout the first 16 chapters, it's to do with where *new* information comes from as organisms evolve over time. An enormous amount of specified information is required to change a putative pre-Cambrian precursor into a Cambrian one. Information, for example in the case of a trilobyte, enabling the formation of the complex arthropod exoskeleton and its accompanying muscles and ligaments, not to mention the appearance of complex compound eyes. The Cambrian predator, Anomalocaris ("strange shrimp"), up to a metre or so long, had very advanced compound eyes, only exceeded in complexity by present-day dragonflies. We even find primitive jawless fish (ancestors of lampreys) appearing in the Cambrian.
It's all quite astonishing and I can't for the life of me see how anyone would prefer to stick with the one theory that can't possibly explain it. I don't know what *does* explain it, but I have to hand it to Meyer, nothing currently explains it better than a postulate of intelligent input of some sort. He probably believes that is the Christian God, but by no means all ID proponents do. I even know of some people who are atheists who think that intelligence may in some sense be inherent in nature in everything from atoms to stars and galaxies to organisms. Maybe some non-ID explanation will eventually be forthcoming that better explains it, but for the moment, ID's at least worth consideration.
Darwin's Doubt is a fascinating read, and for its content alone, it's worth 5 stars. However, it is not entirely without fault, because in places it seems somewhat repetitive and in need of tighter editing, which might have reduced its size appreciably. So overall, I'll give it 4 stars along with a recommendation for any independent-minded person to read it. Don't pay a lick of attention to 1-star reviews from ideological neo-Darwinists who obviously can't bring themselves to read it, yet nonetheless feel it's okay to carpet-bomb the Web with their ill-informed comments. They have little integrity and even less good manners.