Sunday, January 3, 2010

Jerry Coyne's "Why Evolution is True" offers evidence for evolution

Agnostic Apatheist, the same reviewer at Amazon whose review of Dawkins' book I so much appreciated, gave a very positive review of Why Evolution Is True by Jerry Coyne, which he claims does give the evidence Dawkins' book lacked. Well, I read Coyne's book and although I believe it probably is a better presentation of the evidence than Dawkins' book, I think the evidence is pretty easily answered.

For starters I'm just going to post the review and I expect to add my own comments as I go.
An Excellent Book on the Evidence for Evolution, October 11, 2009

This is one of the best books on evolution for the interested layman. It is much better (and far more persuasive) than Dawkins' Greatest Show on Earth. Unlike other books that merely target and rebut creationist criticisms, this book actually provides a fair amount of positive evidence supporting evolution. Unlike Dawkins, Coynes doesn't speculate much or present hypotheses that are untested and remain speculative. He focuses his book on the actual, confirmed evidence for evolution from the various fields of science. Moreover, Coynes writes in a readable and enjoyable style that made it very difficult for me to put down the book.

Chapter 1: What is Evolution?
Coynes begins by first defining evolution. There are many misconceptions, especially among the general public.

Chapter 2: Written in the Rocks.
Here, the author takes us through a tour of the fossil evidence. While much of the evidence he provides is not new, he includes photos and a bit more detail than some other books, explaining why a given fossil is viewed as evidence for evolution.

Chapter 3: Remnants - Vestiges, Embryos, and Bad Design
As the chapter title states, this section is about vestiges, atavisms, embryology, and poor design. Each of these are explained, and experimental, as well as modern observational evidence, is cited and discussed in support of evolution. In fact, he provides quite a few examples of each using various species (including humans) as examples. He also clearly explains the distinction between vestiges and atavisms and why these are best explained by evolution, as opposed to any alternative hypothesis or theory.
There is an alternative hypothesis that explains this as well or better than evolution does, but unfortunately it's hard to lay it out without referring to the Bible. That really shouldn't be a problem to a truly scientific mind but in any case I'll try to keep it to a minimum. The alternative hypothesis is that the earth is young, all things were created in a particular time period, in the Beginning, and no living thing was created subject to death. Death occurred to all living things when the first human parents disobeyed the Creator. It is a mistake to keep expecting to find perfection in nature, assuming that all things continued from the beginning as they were created. Some creationists make this mistake. What looks like bad design is the result of disease and deformity and death in living systems. Vestiges in this explanatory system are easily explained as formerly functioning parts or organs that eventually lost their function as the result of these disease processes.
He also briefly discusses pseudogenes (sometimes referred to as "fossil genes") as evidence for evolution. (For more discussion on pseudogenes, consider reading "Making of the Fittest")
Pseudogenes also fit into this explanatory scheme as formerly functioning options in the genetic code that were damaged or completely lost their function over many generations. The great death brought about by the Flood of Noah alone should have wiped out a great deal of the genetic code as it wiped out the majority of all living things. Probably the majority of the dead genes would have coded for beneficial or protective physical functions of various sorts, simply based on the supposition that the pre-Flood world even in spite of the Fall retained a great deal of the initial blessings, strengths and capacities from the Creation. (There is also a pretty Far Out possibility that is hinted at in Genesis 6 according to some: that is, that the DNA was being corrupted in various ways before the Flood, by fallen angels seeking to destroy the messianic line promised by God from Eden, and this might be evidenced in some pseudogenes that show there were once some pretty odd characteristics packed in those formerly functional genes -- nonhuman characteristics in human DNA for instance This sort of corruption is also hinted to have been the major reason for God's bringing the Flood).

Chapter 4: The Geography of Life
This chapter is about biogeography. It provides evidence for why scientists do not accept the view that the Earth is only 10,000 year olds old. It's not merely that radioactive dating (and other dating methods) suggest a very old Earth. But biogeographical evidence, supported by the modern theory of plate tectonics, can only account for the observations that we see today, with respect to the distribution and types of organisms found at specific locations around the globe.
The phenomenon of continental drift explained by plate tectonics is very useful for creationists as a matter of fact, and does help explain the way species are distributed around the earth. It also explains how the mountains formed and buckled the strata left by the Flood. We understand it all to have been set in motion as a result of or as part of the worldwide Flood event. Volcanism was another part of it. All this was new with the Flood. Otherwise, the main thing that is different in this scenario is the shortened time factor. We think of the continents as moving apart quite rapidly and gradually slowing down. Of course this is just a hypothesis at this point.
Chapter 5: The Engine of Evolution
This chapter is about natural selection. Coynes explains that natural selection is not a random process, as many creationists claim. He also clarifies the concept of randomness. It isn't quite the same as "chance". Rather randomness refers to the occurrence of a mutation, regardless of whether it is beneficial, harmful, or neutral. It does not refer to luck or chance; thus, he uses the term "indifference" in place of random to make this distinction.
Natural selection, along with all the other processes that isolate populations, is a mechanism for change (adaptive in the case of NS, neutral in most other cases, even bottleneck), but in bringing about the change it also brings about reduced genetic diversity, and reduced genetic diversity is the opposite of what is needed for evolution to continue. The more selection the less ability to continue to change. This defines the built-in end to evolutionary processes. Selection itself brings evolution to a halt. Evolution defeats evolution. This makes the question of randomness irrelevant but I will probably have some thoughts about that later anyway.
Chapter 6: How Sex Drives Evolution
Here, Coynes discusses sex and how the development of sexual reproduction affected evolution, as well as what animals (and plants) do to enhance the potential for sex/ mating.
Sexual selection may explain some very odd characteristics of living things, but it does nothing whatever to further the idea of evolution beyond "microevolution."
Chapter 7: The Origin of Species
After covering a wide variety of subjects related to evolution and providing great support for common ancestry and natural selection as the mechanism for adaptive change, Coynes has finally set the stage for presenting the origin of species.
Natural selection, along with all the other processes that isolate populations, is a mechanism for change (adaptive in the case of NS, neutral in most other cases, even bottleneck), but in bringing about the change it also brings about reduced genetic diversity, and reduced genetic diversity is the opposite of what is needed for evolution to continue. The more selection the less ability to continue to change. Thus evolution stops with "microevolution." This defines the built-in end to evolutionary processes. Selection itself brings evolution to a halt. Evolution defeats evolution.
Chapter 8: What About Us?
Inevitably, a book on evolution would not be complete with at least some discussion of human evolution. He covers a lot of material here, but the information is invaluable for any non-biased individual who truly wants to know whether humans are exempt from evolution (i.e. a special creation of a higher power). The answer is "No". We too are the product of evolution.

Chapter 9: Evolution Redux
Finally, we come to the last chapter. Coynes discusses evolution and its implications for understanding human behavior, human psychology, and human nature.

After reading this book, it will be clear why scientists accept evolution. It is the best (and only) scientific explanation for the diversity of life on Earth. Moreover, there truly are no compelling alternative hypotheses; no other hypothesis has the breadth of support from various scientific disciplines or the ability to make accurate predictions (which are later confirmed).

Two criticisms I had - (1) I wish more detail was provided. But given the audience that this book was likely geared toward (i.e. the non-scientific, general public), this is a minor criticism; (2) As a student of philosophy, I did not like the title. The term, "true" or "truth", has a different meaning to me than it likely does to Coynes or other applied or natural scientists. But again, this is a minor issue.

1 comment:

  1. Where did civility go? Among people who defend evolution, this sort of remark is unfortunately typical, an attack on the person instead of a consideration of the person's argument. This person's website is full of such stuff.

    Do I think I know more about biology than all the world's biologists? I don't think that's shown by anything I've written here. I think I have a sufficient understanding of a limited portion of a limited area of biology, population genetics, which I've made it my business to understand because I've come to believe it shows the impossibility of evolution.

    ReplyDelete

PLEASE just register somewhere, there seem to be many options. A Google account is easy. And give SOME kind of pseudonym at least. THANKS!