I’ve just finished a several week virtual book club with a friend in Colorado.  We both downloaded and listened while driving, to Richard Dawkins’ latest book on evolution, The Greatest Show on Earth: The Evidence for Evolution.  During the day one of us would call the other to appraise our progress, go over what struck us the most, or what was most difficult.  In addition we kept up a shared document at Evernote, an Intenet based note-keeping site.  We wrote up salient points from Dawkins’ arguments, posted links to supporting material and pasted in charts, photos and cartoons that seemed apropos.

Dawkins, along with the late Stephen Jay Gould, is one of the most widely read explicators of evolutionary biology in the world.  Unlike many of his peers, he takes on with gusto the assertions and beliefs and confusions of  creationists, in all their camps.  His Blind Watchmaker, 1986, was an earlier attempt to show how evolution — “the nonrandom survival of randomly varying hereditary equipment”, as he calls it — can explain the complexity of all biological beings, including man.  There is no need to posit a skilled “watchmaker,” e.g. God, to account for us.

The Greatest Show was written to coincide with the 200th anniversary of Darwin’s birth, in an effort to close what Dawkins felt was a serious gap left by his previous six books.  All of them assumed evolution to be true.  “Looking back,” he says, “the evidence for evolution itself was nowhere set out.”  Thus this book, an impressive, serious presentation of the current state of knowledge not only of the paleontological evidence but of cell growth and behavior, DNA replication, proteins,  enzymes, structural homology, bacterial experimentation and much more.  Every chapter deserves second readings, particularly when the material or connections between arguments is new to the reader.

The problem is however, he has another central preoccupation — the worrying success of creationists, with lots of money and well crafted obfuscations, at casting doubt on evolutionary theory and on much of science itself.  [42% of American believe life has existed in its present form since the beginning of time, according to a 2008 Pew poll.] The problem is not just one of intellectual disagreement — which Dawkins has had plenty of with Gould and others, but that “when [teachers] explore and explain the very nature of life itself, they are harried and stymied, hassled and bullied, even threatened with the loss of their jobs.”  Thus The Greatest Show is written very much with the creationist arguments in mind.  Pains are taken to show the silliness of many of them.  Winding the two themes together, however, has led to a book that doesn’t quite succeed in either.

A book, fiction or science, has to begin with a sense of the audience: who is going to be reading the book.  In Dawkin’s case, is he really trying to give evolution doubters the irrefutable evidence and logic of evolution?  Is he really trying to persuade them, confident in the power of reason, inference and proof?  Or, is he trying to show those who are already quite convinced of evolution how silly and unthoughtful the doubters are, and grow the depth and detail of knowledge for  those already in the club?  What does the opening to chapter 4 tell us about this?

“If the history-deniers who doubt the fact of evolution are ignorant of biology, those who think the world began less than ten thousand years ago are worse than ignorant, they are deluded to the point of perversity.”

Unlikely, it seems to me, that his following arguments will be persuasive to those he has insulted.  Of course, it may be, given such beliefs, nothing at all will ever persuade.  Why then make the effort?  Why not simply help the rest of us with a step-by-step building of the evidence, including an rigorous introduction to scientific method and its nomenclature?  Dawkins certainly has the knowledge and the material.  Most of it is in the book itself, though not ordered and fitted together in a way to make it easy to recapitulate.  And much of it is laced through with the don’t-suffer-fools-lightly tone that may bring on cheering in some sections, but is a distraction to those just trying to get at the facts.

A book setting out the evidence for evolution in a step-by-step way really is a book about how we know what we know.  Mere assertion, as he does throughout, is not enough.

Following an interesting chapter showing how man has learned to breed dogs, cattle, plants to different ends — Darwin’s starting point, as well– he goes on to say the same has happened with insects.

“Roses tell the same story as dogs but with one difference… The flower of the rose, even before human eyes and noses embarked on their work of genetic chiselling, ows its very existence to millions of years of very similar sculpting by insect eyes and noses…”

Yet he doesn’t tell us HOW we know this.  It will seem to be obvious to many readers, but to those unsure, or suspicious, it will not.  Why do we think this is true?   What do we know now?  We know, for example, without certain pollinators, certain plants will not grow.  We know certain plants and insects live in close proximity to each other, and separated, neither will reproduce.  We know from the fossil record there was a time of plants with no flowers, and then a time of small and few flowers, increasing through time.  There are many other, similar steps that allow us to infer,  a most powerful tool as he argues early, that indeed flowers and insects have shaped and determined each other.  It seems to me, an approach like that, adding up the evidence,  would be more effective, and more memorable.

As in geometry.  What are the essential definitions and postulates?  What are the findings and how do they fit together?  Dawkins early clarification of “theory” for example is useful.  He separates it from hypothesis, and the popular understanding of “theory,” which is essentially a synonym for “idea.”  He shows how a mathematical theory is different from theories in science, and yet how powerful the latter are, as explanatory schema for a wealth of interrelated observational and inferred evidence.   He could have gone further, in fact, showing how theories are said to have descriptive power, and explanatory power, and given examples.  And, in my opinion, had he appended remarks about the silliness of creationist claims that evolution is “only a theory”  instead of leading with them, the chapter would have had more power.  As it is, the reader is distracted by the polemic and less attentive to the building block.

Following a clarification of language and method in science in general, and evolutionary biology in specific, the most basic building block to understanding what we know, is a discussion of time.  How do we measure time on earth.  How do we know that something is 100 years old, 1,000 years old if we aren’t there to witness?  Dawkins does a good job of this. His discussion of tree-rings as measuring seasonal change, and thus years, and how that overlaps with certain atomic clocks is exactly what the book should be doing to help us understand.  His discussion of isotopes and instability leading to decay is elementary and clear.  We get how it can be determined that natural objects, stone, sand, fossils, oil, can be dated.  We get — though he does not emphasize this enough– how the tools used to understand evolution are the same tools used in all the rest of science.  To deny their utility in the one would be to deny the obvious and accepted in the other.

His chapter on evolution happening before our very eyes is one of the most interesting.  He cites numerous examples from the bacterial to the mammalian of how fast, under proper circumstances, change can happen.  Lizards transported from an insect rich habitat to an insect poor habitat change jaw and tooth shape and size, as well as internal organs to deal with the change in diet from insects to plants.  One set of bacteria, in an identical environment as another set, are suddenly able, through a mutation, to make use of citrate, common to both environments but not previously used as food.  Yet another example of guppies changing colors and sizes depending on the environment and predators.  Fascinating stuff, and if not probative of how evolution did happen, certainly showing how it does happen now.

He spends a good deal of time helping us understand the falsity of the “missing link” idea, essentially by showing that it is a false notion.  In all mother-daughter sequences in no case is the daughter a different species than the mother.  Change happens in infinitesimal steps.  Each generation is indistinguishable from the next.  It is only over great periods of time that we can discern separation, due to climate, food, predator change large enough to notice, and finally to be different species.  This is no “missing link” between man and ape because both species flow in infinite gradations from a common ancestor tens of thousands of years ago.

One of the most helpful sections for me was the explanation of how individuals, cells or starlings, following local rules, could produce greater-than-themselves structures, with no guiding grand plan.  His discussion of the dead-end of the idea of preformationists, who believed that the egg, or the sperm, contained a miniature human being, only needing nourishment to grow, conjoined to a very useful explanation of why DNA is not a “blueprint,” were immensely helpful in building the case for the slow, infinitesimal “epigenesis” of the human body, not being built according to a grand master plan, with the liver being shipped in to occupy a sketched out master plan, but rather the cell-to-cell growth, with different local rules creating changes in cells from organ to skin to bone.

Other chapters include continental drift and how that, along with other “island” creating episodes created the external changes living organism had to adapt to; random changes in individuals giving greater chance of offspring survival until that line was dominant in a particular environment. In my building block sense, I would have preferred this chapter to come earlier — showing how, in modern jargon, every geologic/environmental change was both a challenge and an opportunity to the creatures involved.

Most intriguing, is his chapter on “cousinship,” how the vertebrate skeleton, and especially all mammalian skeletons, are so similar. Pictures and descriptions of bat wings/arms and fingers are especially evocative but as he says ” The skeletons of all mammals are identical, but their individual bones are different.”

“History written all over us” is a further exploration into the similarities between the species, pointing back step by step to one common ancestor.  Explanations of fish swim bladders becoming lungs as they adapted to land, of marsupials filling environmental niches unoccupied by mammals, in Australia, of the different adaptations of wings in flies, birds and insects of all kinds are all very interesting in themselves and add to the grand edifice of interconnected evidence and knowledge about life on earth.

Though I think Dawkins disturbs his presentation with too much quarreling with the quarrelsome I admit I am not in his shoes.  It’s hard not to say “you are an idiot” to someone who acts like one.  In a sense, however, it is like trying to argue with a brat, who is interested not in knowledge, but in scoring points in some kind of language game.  “It’s only a theory” indeed.  Had Dawkins been able to re-cast his caustic comments, and craft a somewhat more “evolving” story of why we know what we know I would have had a more shapely set of arguments to retain and use, when the occasion demanded, in arguing with the demented. ;-]

It would be interesting to know that evolution is not true, or we all arrived in some other way.  Space ships, or Noah’s Ark.  All the creationists have to do is explain, with thoughts and facts that fit all the rest of what they hold to be true,  what the case is.  How is it, as Dawkins wonders, that marsupials left the Ark and got all the way to Australia, leaving no evidence of their passing across the great land mass of Asia?  How is it that mammal skeletons are all the same?  That DNA is so deeply shared?  Take all the known data, make inferences that logic and experience allows and come up with another explanation.  Curious minds want to know.  But picking apart another’s arguments, citing “holes” in the evidence, is not doing science of your own.  It is not even providing answers.  Feel free to explain things in new ways, but do the work. Don’t just complain about the work of others.  Tell us what you know.

“God did it” is not an acceptable answer.

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So, do I recommend The Greatest Show on Earth?  Depends on who you are.  It’s a serious read.  You will want to take notes, flag pages for reference and have time to google up supporting, or questioning evidence.  Extracts of Chapters 1 and 2 are available on his website, here.  For an easier introduction I’d suggest the Blind Watchmaker, or his own favorite, Climbing Mount Improbable.  Or go to his own very interesting web site, RichardDawkins.net and look at his essays and other material.

Some of his colleagues have produced books that might be more intriguing reads, while giving the essentials of evolution.  One I am particularly interested in is Your Inner Fish: A Journey Into the 3.5-Billion-Year History of the Human Body , by Neil Shubin.  Jerry Coyne’s Why Evolution is True, received praise from Dawkins, and at least one escapee from the creationist camp. And even, believe it or not, watch the pretty good Discovery/BBC program called Life, narrated by no less than Oprah!  It’s not a through lesson of course but is  passably good and hits the right notes on evolution — evolution happens because of struggles between individuals, not between species. Survival selects the genes that reproduce…   It’s really a mind-blowing idea.  Still turning the world upside down.