Saturday, October 31, 2009

Book review: Why Evolution is True

This is one of those great science books that the people who need to read it the most will never touch.  It is, as the dust jacket blurbs promise, a succinct and thorough evaluation of evolutionary theory written in terms a nonscientist can easily understand.  The author, Jerry A. Coyne, summarizes the Charles Darwin's 19th century work in early development of evolutionary theory, lays out the theory's key ideas -- evolution, gradualism, speciation, common ancestry, natural selection, and the recognition that processes other than natural selection can cause evolutionary change -- and then explicates in detail each of those concepts.  The book explains evolution clearly, concisely, and stacks up so much supporting evidence it's guaranteed to make a creationist's head explode.

Coyne begins with the basics:  what is a theory in science?  One of the mantras of the creationists is that evolutionary theory is "just a theory."  Saying that labels the speaker immediately as someone who lacks a basic understanding of science and how science works.  Of course evolutionary theory is just a theory, just as gravitational theory is just a theory; so what?  In science a theory is a possible explanation or collection of related explanations used in an attempt to understand a fact or phenomenon.  Evolution is a fact; the evidence is all around that organisms evolved and continue to evolve; evolutionary theory explains evolution. 

But more than explain a phenomenon, a scientific theory has other properties:  it has to be testable, or potentially falsifible.  In the case of evolutionary theory, when we're surrounded by ongoing, continuous evidence of it happening (pandemic influenza A(H1N1) 2009 being the most recent example to spring to mind), what would falsify it?  Finding fossils known to be from organisms that lived in one distinct geologic era embedded in rock side by side with organisms from another could do it.  An obvious example would be fossilized mammals, which first appeared about 250 million years ago, embedded in geologic strata from a much earlier time period, like the Silurian (over 400 million years ago).  This is one reason some creationists will go to extraordinary lengths to try to prove that humans co-existed with brontosaurs (they apparently think The Flintstones was reality tv). 

Another way to disprove a theory is to use it to make predictions -- and if the predictions don't come true, then the theory may be fatally flawed.  Unfortunately for the doubters, evolutionary theory to date has proved remarkably accurate in its predictions.  A criticism of evolutionary theory used to be that various transitional forms did not exist, e.g., if, as scientists claimed, creatures like whales evolved from land mammals then there should be fossilized whales with legs.  I know a few folks who were quite proud of making that argument 20 or 30 years ago.  Bad news for them:  paleontologists have found a veritable plethora of legged whales, the transitional forms between land mammals and marine.  Evolutionary theory predicted not only that such forms would be found, but in what geologic era.   

In short, Coyne's book explains evolutionary theory and provides numerous examples to support it. The book is extremely readable and loaded with interesting tidbits from the history of science and the natural sciences.  Unfortunately, as Coyne himself admits, even though one would think so much compelling evidence would help to change a few minds, it probably won't. 


  1. This comment has been removed by the author.

  2. I did a lot of reading at one time about the whole evolution-creationism debate and frankly got a little annoyed by the religious belligerence of BOTH camps. The title of this book puts me off for that very reason. Scientists who speak of theories, no matter how well supported to date, as truth, should be steered well clear of in my humble opinion. I think people tend to attribute to evolution supernatural powers. :)

    I remain humbly agnostic on this issue.

  3. Unlike your previous commenter who prefers to live in ignorance, I will seek out this book and read it. Thanks for posting about it.

  4. Mulled, you've misread what I wrote so I'll reiterate. Evolution is a fact; evolutionary theory attempts to explain it just as gravitational theory attempts to explain gravity and the theory of relativity attempts to explain fundamental physical facts about the universe. No scientist ever claims a "theory" is true; he or she just presents it as the best possible explanation available at that point in time. Evolution and evolutionary theory are not the same thing.

  5. The equivalence posited in the first comment underscores the dismal state of science education in the country today.

  6. Also, opposing the first commenter, thanks for your insight into this book. I'm sure my son will be interested, if he hasn't read it already. I shall seek this book out immediately.

  7. I won't be reading the book but I learned a bit about evolution way back as a child and I've always believed in it. Everything points to it, and the brainwashing crap in bibles just insults me so I'm sticking with evolution.

    We're just waiting for science to prove it all is all.

  8. Thanks for the review! Its going on my booklist - always searching out extra ammo - err.. I mean facts :D


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