A reader writes:
In your post you picked a section of Jerry Coyne's review where he suggests that observed changes in characteristics such as weight, cholesterol, age of menopause etc are "evolutionary change" and evidence that our species is evolving. My first two reactions were "wow, could they have picked a worse set of characteristics to study?" and "wow, how could he possibly draw that conclusion?" There is not a single characteristic listed which is not significantly affected by the lifestyle and environment of the subjects, something which any layman can readily understand.
Despite his own caveats, where he notes that even the authors of the paper point out that the study was unable to differentiate between the effects of genes and culture, he still draws the conclusion that this is evidence that humans are evolving. The problem with his 'probable assumptions' is that they are speculations (by no less than his own admission), not science, which have been lent some air of authority due to the author's position as a prominent proponent of evolution. He also notes that these predictions will be hard (perhaps he should have said impossible) to verify due to the very same reason which I believe make them completely unreliable as indicators of evolution in the first place, namely that the behavior of the population effects these characteristics.
His conclusion also takes the concept of evolution completely out of context. He goes out of his way to let his readers know what evolution is in the review, that an individual will possess a trait which will increase the individual's chance of producing offspring and passing on an inherited advantage, but then goes on to declare these changes to be "evolutionary." The only way which this conclusion is reasonable is if you expand the definition of evolution to include learned behaviors, which he actually does in his first caveat, and introduces Richard Dawkins' idea of 'memes' without giving it the name, which is yet another area of speculation. By this reasoning a person who changes their diet and loses or gains weight has evolved.
Regardless of whether or not behavior is considered a part of evolutionary theory, it was not the point of the study, which was to find a connection between genes and the specified changes. This reminds me of Barack Obama's promise that the stimulus would "save or create" a certain number of jobs. A brilliant political move considering it is impossible to truly measure how many jobs are saved. Both of these cases demonstrate a common method of appearing to have successfully accomplished a desired goal by making goal posts sufficiently ambiguous as to make it possible to claim accomplishment where there is, in reality, none.
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