(The first paragraph is basic stuff which everyone is totally familiar with. It is there to contextualise the next bit)
If females within a population fancy males (this may itself be an evolved response with a genetic component) with green tail feathers at a slightly higher rate than they fancy males with blue tail feathers, then males with green tail feathers will reproduce more successfully than those with blue. The tendency towards green tail feathers moving to fixation is the summation of individual female choices, but results in the fixation of one characteristic-determining allele and the extinction of the other in the whole population. One of the ways you can now distinguish between this species and one that is evolutionarily close to it is by the green outer tail feathers of the male. This is a simplistic account, but with broad brush strokes represents the case.
In this case the proximate selecting environment is composed of the individual females in the population. In the case of stone handaxes the proximate selecting environment is the collective population of human organisms. Each individual human organism can be analytically resolved into tissue, blood, muscle, bone and central nervous system. In order for any thing-in-the world to be replicated, it must pass into the hub of the human CNS, via the eyes, ears or tactile and proprioceptive nerves, and exit again via muscle contraction as yet another handaxe. However what is necessary for evolution to happen is a population of handaxes replicated with fidelity but with a sufficient envelope of marginal variation for selection to work on. This requires not just one but many human organisms to be producing a large number of more or less identical handaxes. In other words the information that regulates replication and variation is not located in any one human brain, but is distributed throughout the tradition of handaxe manufacture as it exists in the at-the-time products of handaxe manufacture and the infrastructure of the industry, and in human organisms, including their individual brains, who are the proximate environment of handaxe production.
This is the significant conclusion, as yet to be fully explored, of the groundbreaking experiment Investigating the Effects of Social Information on Individual Ability at Refining and Understanding a Physical System, Derex, Bonnefon, Boyd and Mesoudi 2018, presented by Maxime Derex at the 2018 Tartu conference.
This explains how each of us can function perfectly adequately in the immediate environment of our extended phenotype, in my case a small town in middle England, and at the same time understand practically nothing about it. I doubt if there is a single person in Market Harborough with enough knowledge to singlehandedly produce an LED screen smart TV with all its connective functions, even if they were presented with all the constituent materials in basic chemical form. I’m slightly doubtful that I could describe in detail the whole electricity generating and distribution system of the UK, let alone single handedly reconstruct it from scratch. I don’t need to labour the point. As a collective, including all the works of the dead, we are by our own standards unimaginably massively intelligent. As individuals we are characterised by our unimaginably massive ignorance of all there is to know. This explains why, though we think of ourselves as intelligent individuals, we notice that most other people, while they tend to have information that we do not personally have, are, how can one put it? I think Uncle Galahad in Blandings has it about right.
CELIA: (of her fiancé) Of course a lot of people might think of Freddie as fairly ordinary.
UNCLE GALAHAD: If that.