In every case of biotic obligate symbiosis between an organism and its extended phenotype, the evolving extended phenotype is a significant part of the symbiont’s evolutionary environment.
That statement sounds like gobbledygook, so let’s clarify a few terms. Obligate symbiosis in biology means when two types, usually two different organisms, are totally dependent on each other; like us and our gut flora. Each without the other would die. Extended phenotype is everything outside the organism that the organism produces, for instance a bird’s nest.
The obligate symbioses of web spinning spider and web, of bird and nest, of beaver and dam, of coral polyp and reef, could never have evolved into its present complexity, or indeed at all, in the absence of web, nest, dam or reef. It is even more obvious that neither web, nor nest, dam nor reef could have evolved without the concomitant organism of spider, bird, beaver and coral polyp.
So the question arises, if evolution of its extended phenotype is so clearly a necessary condition of the evolution of each of these obligate symbionts in the natural world, why is exactly the same not true of the line of evolution in the natural world that led from early hominins to homo sapiens? I can think of only two possible answers.
The first is, it isn’t true because Homo sapiens does not have an extended phenotype. Nothing exists outside the envelope of our bodies that has in any way been mediated by the brains and muscles of our species. That may be true, but if so we must find another way of accounting for the thirty trillion tons of the technosphere that has brought about the mooted new geological age of the Anthropocene; all those houses, cups, knives, factories, cathedrals, mosques, steel, plastic bags, aeroplanes, disposable coffee cups, smartphones, concrete; like I say, 30,000,000,000,000 tons and rising exponentially. If human brain and muscle did not produce them, what did?
The second answer is more an explanation of why we don’t believe that our extended phenotype has anything do with who we are. Human beings, like all animals, are very conformist. We do what others do and we believe what others believe. And very often what others believe is not in fact the case. As Daniel Kahneman says in Thinking Fast And Slow, “People can maintain an unshakable faith in any proposition, however absurd, when they are sustained by a community of like-minded believers”.
Since Charles Darwin’s On the Origin of Species was published in 1859 we, the “universally educated”, have notionally subscribed to the hypothesis that we humans are not the Abrahamic God’s special creation but, like all the living world, organisms that evolved over more than three billion years from one prokaryotic common ancestor. But 1859 was only around a century and a half ago, and the deepest held human beliefs just don’t change that quickly. Added to which even the most educated people have no idea of the simple ground plan of Darwinian evolution, and that seems to include an awful lot of academics who practise the narrative arts of sociology, anthropology, psychology and history. So the latent and opaque belief that emerged probably within the last ten thousand years is still with us in all its archaic glory. It still says, in a roundabout and obscure way, that we are creatures formed in the Creator God’s image, and that the technosphere, let us say the Taj Mahal or the Large Hadron Collider, are not a result of our evolved symbiosis, but are spontaneous products of our “creativity”, the secondary, material outcome of our “thought” and “reason” and “imagination”. Most academics in the field of human evolution are alongside Yuval Harari when he writes, in his world-famous history book Sapiens, that the whole technosphere is a result of a genetic mutation around seventy thousand years ago, which resulted in a miraculously transformed brain, the Cognitive Revolution, the “fully modern mind”, and the thirty trillion tons of the technosphere.
I, and very few others in the narrative arts, in fact very few others outside evolutionary science, do understand the ground plan of Darwinian evolution which is, in a nutshell; observed phylogenetic heritability, incessant replication with fidelity, an envelope of fractional variation, selection by external factors.
And, rather than the miracle working of sociologists and cognitive evolutionists, I propose the following narrative, which depends not on one single huge genetic leap from animal to human, but on the evolution of the hominin organism and its extended phenotype in tandem over three million years.
It starts a few million years after our evolutionary line separated from the chimpanzees, the time when the notional first hairy Australopithecus to have in its apish brain an ability not only to recognise, when it saw one, a stone suitable for hammering, as apes do, but also to recognised a stone suitable for cutting, as apes don’t seem to; and beyond that could maintain in the architecture of its brain this registration of difference when it looked away from the stone suitable for hammering, or the stone suitable for cutting. What is more, it could retain that difference through periods of distraction, not for minutes but for days. It is in the space of that difference that over the thousands of millennia of evolutionary time, meaning emerged.
And as evolutionary time continued its slow pace, and hammer stones were used in more diverse ways, the descendants of those hairy organisms began to recognise not merely found cutting stones, but stones that were suitable for cutting that resulted from the impact of one hammer stone on another passive stone. And, the final bit of slow, slow evolution that separates hominin from hominid, they not only recognised the moment of percussion and its immediate effect but, as with the recognition of difference between a stone used for hammering and a stone used for cutting, they had a durable registration in the architecture of the brain of the spatio-temporal relationship of the kinetic striking stone and the inert stone that was struck and from which fell flakes, stones good for cutting. And they could retain this brain registration through episodes of distraction. That is to say, they could remember it.
And that emergent ability became the obligate symbiosis of human organism and human extended phenotype; eventually of Homo sapiens and the technosphere. The primitive, emergent technosphere of hammer and cutting stones became a significant part of the evolutionary environment of the human being.
That is the most significant, and the most crucial and necessary basis of the emerging science of cultural evolution that we need to grasp.