It seems humans instinctively juxtapose environment and biology, as if the two are not simply part of the same continuum of the natural world. From page 221 of Genome:

Humans beings achieve by instinct the same things that animals do. We crawl, stand, walk cry and blink in just an instinctive a way as a chick. We employ learning only for the extra things we have grafted on to the animal instricts: things like reading, driving, banking and shopping. 'The main function of consciousness' wrote Baldwin, 'is to enable [the child] to learn things which natural heredity fails to transmit'.

And by forcing ourselves to learn something, we place ourselves in a selective environment that puts a premium on a future instinctive solution to the problem. Thus, learning gradually gives away to instinct. In just the same way, as I suggested in the chapter on chromosome 13, the invention of dairy farming presented the body with the problem of the indigestibility of lactose. The first solution was cultural - to make cheese- but later the body evolved an innate solution by retaining lactase production into adulthood....