Tuesday, September 06, 2011

Book Review - Greatest Show on Earth

I finally finished Dawkins' Greatest Show on Earth. I bought the book shortly after it came out, and worked through most of it quickly before losing interest. I picked it up again this past winter and again, quit before finishing. Once again, I tried this summer and made it nearly as far as I did the first time, but having read it so many times, it stuck enough for me to quit for awhile, and come back without feeling the need to start over.

I still haven't figured out exactly what it is about this book that's prompted me to quit midway through three separate times. The book starts off introducing a little bit about how science works and what it means to be a "theory" in science. This is old hat for anyone that's been involved in the evolution "debate" so there's little new information here, but the thing that interested me the most was Dawkins' call for a new word to replace the frequently abused "theory". Likening a scientific theory to math, he calls for the term "theorum", a twist of mathematical theorems which are accepted as true even though they're often impossible to prove since there's an infinite number of cases in which they could apply.

The next several chapters work to build up an understanding of how evolution works, from scales that are uncontroversial, even to Creationists (who accept "microevolution"), gradually to larger and larger scales, through dogs, cows, and computer generated biomorphs, showing how each transition has been supported by observation.

From there, he discusses the "Primrose path to macroevolution", taking this even further. While the chapter doesn't truly demonstrate anything that could readily be called "macroevolution", its goal is to set the framework for diverging populations that will then be able to grow apart even further, if only there would be enough time, which is the topic of the next chapter. That chapter explores dating methods, like dendrochronology and radioisotope dating.

Of course, some changes don't take deep time to achieve and the fifth chapter explores rather astounding changes that take place within our own lives. I think the most interesting was a series of experiments with guppies, placed in isolated pools with different rocks on their beds, some with predators, some without. The variation from this was a fantastic demonstration.

Moving still, towards larger scales, the next chapter covers a bit of the fossil record, explaining the supposed "gaps" and just how little that really means. This is followed by a chapter which focuses even more on the recent fossil record that chronicles the development of humans and just how detailed the record is for supposedly being non-existent as Creationists claim.

The 8th chapter was the one that slowed me down the most every time. This one covered much more on the microbiological side, involving DNA and how it created forms through embyrology. It's not that the topic wasn't interesting, but rather, much of the material became very informationally dense at this point, and the chapter seemed to drag.

But once past this chapter, I think is where the book really began to shine. The last chapters really get to the meatiest portion of the book, providing the most clear cut evidence presented in the most direct fashions. Chapter nine discusses how the motion of continents isolated populations of one species, allowing them to diverge. Chapter ten covers family trees and the numerous ways they can be derived (from homology or genetics) and yet they always come out to agree. It also explores how non-coding genes can be used as biological clocks that also agree with other dating methods. Chapter eleven is about vestigial structures and provides some new examples beyond the usual ones which was refreshing. It also explores things that aren't vestigial, but that got caught up in evolution in other ways, like the vagus nerve.

The reason these chapters stood out to me is, in each one, they can be starkly contrasted with ID/Creationism. They all make sense in the light of evolution, but make the designer inept or deceptive (similar to the argument put forth in Miller's Finding Darwin's God, but not so plainly stated here). With ID/Creationism, each of these cases requires special pleading.

While the first several chapters made a good case for the idea of evolution, complete with steps along the way to bolster it, these last few chapters are the ones that really slam the nails in the coffin.

There's two more chapters. Chapter twelve explores the apparent stillness of evolution where arms races meet stalemates or have to keep changing just to stay in the same place, but nothing here is really a strong argument for evolution. The final chapter is a line by line discussion of the final paragraph of Origin of Species, putting each piece into the context of how Darwin's idea has been realized. It's a cute summary, but ultimately added very little to the book. If I were to reread this book, I'd skip it.

Included is also a appendix which includes studies of just how frequently evolution is rejected in various countries and seeks to put in context the scope of anti-evolutionism. I skimmed this, but didn't bother with it too in depth since the problem is already obvious.

My overall impression of this book is that it's good, but not exactly the slam dunk I think it was intended to be. Too much gets lost in the noise and isn't summarized clearly enough to really bring the full weight of the book out. This book could have been much better if each chapter contained some end notes that summarized the main points to clarify what the intent of the chapter was. Without them, it's easy to get lost, which is why I think I gave up so many times. The book lacks a direction that's immediately obvious. In retrospect I can see it, but that only works if you've completed the book, which isn't likely to happen unless you're as stupidly tenacious as me.

So who is this book worth recommending to? Obviously not Creationists. They've likely heard most of this anyway, and have the constant strategy of seizing on the details and finding bits they don't understand to hold up as "counter evidence" or simply moving the goalposts. In reading many segments of this book, a passage from the first book I reviewed on this blog, Science of Diskworld III, came to mind:
Yes, the proponents of intelligent design understand the eye . . . but as only one example, not as the basis of a general principle. ‘Oh yes, we know all about the eye,’ they say (we paraphrase). ‘We’re not going to ask you what use half an eye is. That’s simple-minded nonsense.’ So instead, they ask what use half a bacterial flagellum is, and thereby repeat the identical error in a different context.
I could just envision Creationists saying, "That's all well and good, but what about [Gish gallop]?" Trying to educate a Creationist is a waste of time.

But what about the middle ground? Those that aren't decided but wanting to learn more about the evolution and ID/Creationism? The first time I've been asked to recommend a book on evolution to such a person happened a few weeks ago with a girl at work. She rejects evolution for all the usual logical fallacies ("Isn't it all too complex?"), but didn't immediately accept ID/Creationism as something that had much science going for it either.

My choices of books to give her included this book, Shubin's Your Inner Fish, and Miller's Finding Darwin's God. (I would also have considered Coyne's Why Evolution is True, but I haven't read it and don't own a copy.) Ultimately, out of these three books, I recommended Miller's. Inner Fish is fantastic, but doesn't give enough direct back and forth between evolution and ID/Creationism that just shows why the latter is wrong. This one has that at the end, but it's simply too hard to get through for the reasons I explained before. Thus, it's not the greatest of books for the uncertain middle ground either.

The last potential audience is those that already support evolution and are looking for a more thorough grounding and a few new pieces of evidence that I haven't seen in other sources. This is about the only audience I think this book can really do much for.

Overall, this book is ok, but not nearly as good as Selfish Gene, which is my favorite Dawkins book of the ones I've read thus far, albeit for different reasons (giving a marvelous naturalistic origin to morals and altruism). I'm happy to have this on my bookshelf, but it won't be likely to get another read any time soon.

1 comment:

Chet Twarog said...

Dawkin's "The Ancestor's Tale", though I have not finished it, is much better. My favorite is "Climbing Mount Improbable", 1996, W.W. Norton and Company, that I have read twice. Check out figure 3.2, pg 97, "Macro-mutations do happen. This freak toad with eyes on the roof of its mouth."