Mixed natural and cultural selection brought about genetic and meaning changes, shaped the biocultural traits of proto-humans, strengthened some of their aspects and weakened others, resulting in psychophysiological, moral-volitional and cognitive distortions in proto-humans. In short, mixed selection shaped human propensities. The new propensities in turn influenced subsequent selection, which in turn strengthened these propensities. Thus, human domestication gradually took place. Long before humans began to selectively breed animals, they began to culturally select themselves. As Matt Ridley says, humans are self-domesticated apes (cf. Ridley 2003, p. 348).

“… Man of his own accord mediates, regulates, and controls the material reactions between himself and Nature. He opposes himself to Nature as one of her own forces, setting in motion arms and legs, head and hands, the natural forces of his body, in order to appropriate Nature’s productions in a form adapted to his own wants. By thus acting on the external world and changing it, he at the same time changes his own nature. He develops his slumbering powers and compels them to act in obedience to his sway” (Marx and Engels 1975-2004, vol. 35, p. 187, translation corrected).

As a result of millions of years of mixed selection, meanings are inscribed in nature itself, in human genes. With the emergence of culture, it begins to influence nature by creating a cultural environment (domus) within the natural environment and domesticating proto-humans to slowly transform them into the modern type of Homo sapience. “In the dialectic between nature and the socially constructed world the human organism itself is transformed. In this same dialectic man produces reality and thereby produces himself” (Berger and Luckmann 1991, p. 204).

The transmission of meanings between people, that is, learning, is based on imitation or mimesis, not on copying. Imitators do not have access to the content of the meanings they must acquire and cannot copy it. Therefore, the learning of meanings relies on active communication with other people, on the acquisition of norms through their expression. From norms, the imitators gradually arrive at the content, that is, understanding. In this way, imitators penetrate new cultural areas and learn meanings that were previously inaccessible to their understanding.

“… The cultural equivalent of the genotype is the information stored in people’s brains that represents their beliefs, attitudes, values, skills, knowledge, and so on. The cultural equivalent of the phenotype is the expression of that information in the form of behavior, speech, and artifacts. It is the latter—the phenotype equivalent—that is copied during cultural transmission: we do not directly acquire neural patterns of activation in people’s brains; we copy people’s behavior, we listen to what they say, and we read what they write” (Mesoudi 2011, p. 44).

In nature, inheritance occurs in a direct order: first, genetic content is copied, and then the genotype, in interaction with the environment, shapes the phenotype, the external characteristics of organisms. Cultural inheritance is indirect: imitation, that is, copying the expression in the plane of norms, precedes the understanding of the content. An idea is passed through the medium. Understanding this difference between the direct transmission of genes and the indirect transmission of meanings was one of the initial problems of memetics, which, starting from the scientific apparatus of genetics arrived at the concept of the meme. “[A] significant worry for memetics is that when the same ideas do spread through a population, it is rarely because they are literally copied from each other” (Lewens 2018).

The evolutionary variation of meanings depends on their correct repetition by successive human generations. The inability of people to authentically repeat a meaning leads to its demise. Therefore, as Henrich shows, people tend to “over-imitate,” mimicking meanings with excessive accuracy (Henrich 2016, pp. 108-9). The ability to improve meanings (or at least not allow them to degrade) depends, all other things being equal, on the size and sociality of the human population. Thus, the size and quality of a society influence the path of its cultural evolution and the adaptive landscape of its meanings.

The difference between indirect cultural transmission and direct transmission of genes means that meanings can negatively affect human survival. If the survival of genes depends entirely on the survival of organisms that possess those genes, then meanings are not strictly tied to their carriers, allowing harmful meanings to spread throughout the human population. “…Oblique transmission opens up the possibility that some traits may spread through a population in spite of the fact that they reduce the fitness of the individuals who bear them” (Lewens 2018). Well-known examples include alcoholism and drug addiction.