In Your Inner Fish, Neil Shubin explores some of the many ways that the human body displays the marks of evolution. Hands, lungs, teeth, eyes, ears, and more are traced back to earlier versions of these body parts in our non-human ancestors, including but not limited to the fish in the title. Along the way you get some insight into the practice of paleontology, as Shubin describes his personal adventures in fossil hunting, and the functions of the various members of his team, such as the “preparators” who spend weeks or even months meticulously chipping a fossil out of a rock with dental tools and such in the lab.
I had already read Shubin’s The Universe Within—which was written later, so I read them out of order—and while there was nothing particularly weak or objectionable about that book, for whatever subjective reason I mostly wasn’t drawn in by it and found myself just kind of trudging through it. I felt noticeably more engaged reading Your Inner Fish. Again, I can’t say with confidence precisely why, so I don’t know if it was due to the relative merits of the books, or something as simple as that I was in a different mood when I read them and happened to be more receptive to this kind of material now than I was then. But Your Inner Fish held my interest reasonably well the whole way.
It is a very non-technical science book, quite easy to follow for a layman. If anything I found that to be even more true of this book than of most books by science popularizers.
Evolution by natural selection is quite the haphazard process, very different from a teleological process where some sensibly-designed creature is decided upon in advance and then is brought into existence through a process of orderly steps. Instead, countless incremental changes occur through mutations over unimaginably long time periods, with the tiny number of those mutations that actually make the creature equally or better able to survive (and most importantly, procreate) being retained.
But these aren’t changes that necessarily make the creature “better” in some absolute sense, or bring it closer to some ideal, and there are far, far more hypothetical improvements that never happen than that do (which is why evolution has not equipped us with jet packs from birth, nor with the infinitesimal amount of intelligence that would enable us to figure out that war is really stupid and we should refuse to participate in it, handy as those features would no doubt be). The result, as Shubin delightedly points out, is that the human body is quite a jerry-rigged looking contraption.
Richard Dawkins, of course, is famous for defending science against religious fundamentalism masquerading as science, but in writing about his The Blind Watchmaker I noted that there is very little in it explicitly against creationism, as it is “more of a positive explanation and defense and appreciation of evolution, than an attack on creationism. It’s a celebration of science rather than an attack on anti-science.”
The same is true of Your Inner Fish, only more so. I don’t think creationism (or intelligent design, or any of that) is ever as much as mentioned. It’s not a defense of evolution against anything, because real scientists know there’s nothing to debate about it. Instead, it’s an enthusiastic description of evolution and some of its implications by a scientist who has never lost his curiosity and awe about the natural world and how it works.
Yet so poisoned is public discourse on this issue that as much as I tried to ignore creationism as a reader as Shubin does as an author, I found my mind drifting back to it repeatedly, thinking how fundamentalists might disingenuously counter various points and such. I wanted to enjoy the science, but it’s so associated in my mind now with political and religious bullshit that while reading I too often felt like I was engaged in some hypothetical frustrating argument with a creationist.
In the end, you really can’t use a book like this to try to reason with a creationist, at least not one who’s fully committed. There will always be some ad hoc way to sidestep any facts, any evidence, if one wants to badly enough.
There is an extraordinary amount of overlap among living things on Earth, and the fossil record is laid out chronologically in precisely the manner you’d expect if evolution were true. Does that “prove” evolution? Not in any absolute sense. Maybe God is a trickster who purposely designed a world that would as closely as possible resemble a world with evolution, but where in fact every species has been around since Creation in its present form. For that matter, maybe God created the world one second ago, complete with (false) memories and such. It seems rather pointless to fool people like that with fake evidence, but hey, we’re not supposed to be arrogant enough to question why God does what he does, right?
But if you can bracket that kind of nonsense and just focus on the science, Your Inner Fish is a solid, informative, interesting book.