3 years ago I wrote
an article critical of “evolutionary medicine” as it was presented in a new book. Recently a correspondent asked me if I thought another book,
Why We Get Sick: The New Science of Darwinian Medicine, by Randolph M. Nesse, MD and George C. Williams, PhD, was a more reasonable approach to the subject. It was published in 1994 and got good reviews from respected scientists like Richard Dawkins (“Buy two copies and give one to your doctor.”) and E.O. Wilson (“bringing the evolutionary vision systematically into one of the last unconquered provinces…”). I was able to obtain a copy through interlibrary loan.
The book was interesting and gave me some things to think about, but it didn’t convince me that “Darwinian medicine” is a new science, that its existence as a separate discipline is justified, or that its unique approach offers any real practical benefits for improving medical care....
....
Why are wisdom teeth a problem? (they say) Modern children frequently need orthodontia and surgery to remove wisdom teeth. They propose a possible explanation: we don’t chew enough. In the Stone Age, food required more jaw exercise. Today softer foods result in deficient use of jaw muscles, which results in poorer development of jawbones so there is less room for all the teeth. They suggest that many dental problems might be avoided if children chewed more gum or engaged in prolonged vigorous biting competitions.
This is nothing but silly, far-fetched speculation. You’ve got to give them credit for imagination; but if this is the kind of thing “Darwinian medicine” produces, we can do without it.
There is a disconnect in their logic. They say
For instance, if we hypothesize that the low iron levels associated with infection are not a cause of the infection but a part of the body’s defenses, we can predict that giving a patient iron may worsen the infection — as indeed it can. Trying to determine the evolutionary origins of disease is much more than a fascinating intellectual pursuit; it is also a vital yet underused tool in our quest to understand, prevent, and treat disease.
We can ask if something acts as a defense. We can ask whether something is a cause or effect. We can ask whether something does more harm or good. We can ask all these questions about
how something works without necessarily needing to ask
why it evolved to work that way....