"It is a conceit of hindsight to see evolution as aimed towards some particular end point, such as ourselves."
(As comments to the Brothers Judd Blog remind us, the same point was made by Steven Jay Gould. See also my earlier post on The Conceit of Hindsight.)
Robin Wilton finds ironic illustration of this point in the curious natural history of the tree shrew, recently reported by the BBC News - Tree Shrew is Heavyweight Boozer. Robin calls this The Shameful Truth, notes that the tree shrew is much better adapted than humans to the consumption of large quantities of alcohol, and concludes
"we don't represent the culmination of evolutionary improvement at all... we're just the ones who couldn't stand the pace".
(As further evidence of anthropocentricity, I note that the BBC News omits the coy inverted commas it would "normally use" when reporting any "human scandal". So much for "journalistic balance" then, huh?)
But it is a distortion to view evolution from a human-centric position - as if the purpose of evolution is to produce a few billion ill-adapted mammals, rather than say a few trillion excellently adapted insects. Given that insects (and bacteria and other creatures) outnumber and outmanoeuvre us so successfully, we can perhaps conclude that our evolutionary purpose (POSIWID) is to provide food for creatures like these that are higher up the food chain.
(There is no virtue or intelligence in being at the top of the food chain, by the way. Many parasites, like mosquitoes, fleas and head lice, feed upon humans and other useful mammals. “Big fleas have little fleas upon their back to bite ‘em, and little fleas have smaller ones and so ad-infinitem.” See http://www.albawest.com/midges.html. See also Bill Bailey on the Insect Nation.)
A simple version of Darwinism suggests that evolution is all about superior adaptation. But what marks humans out from other species is our singular lack of adaptation. Aha, says the Conceit of Hindsight, but our lack of adaptation to any specific unchanging environment means we are supremely adaptable to a wider range of alternative and fast-changing environments. Therefore the purpose of evolution is to produce, not adaptation but adaptability (Bateson).
But what this does is apply POSIWID at a higher logical level (to the second-order effect rather than the first-order effect) in order to preserve our notion of human superiority and the upward progress of evolution (the Ascent of Man). Isn't this just cheating?