Journal article Open Access
The steady growth of hominin cranial capacity during the Lower and Middle Paleolithic (L/MP) supported the emergence of controlled vocalizations, orchestrated mimetic techniques, deductive tracking skills and exogrammatic information storage. ‘Exograms’ are defined as memory traces stored outside the brain as consciously-sequenced information packages meant to stabilize abstract calibrations of reality. The first instances of their use document the universal emergence of a species-specific objective state of consciousness. Although the ability to produce them is a biological development, the transmission of exogrammatic meaning becomes culturally-conditioned. As all the faculties listed above were in place long before the Aurignacian, the Upper Paleolithic (UP) ‘revolution’—unlike the L/MP transition—cannot be attributed to changes in the size or shape of the cranium. The period was rather characterized by accelerated cognitive specialization to deterministically-predictable cultural niches constructed in unreliable environments. By adapting to their calibrated models of reality, archaic populations underwent rapid physiological/psychological transformations. It is contended that the UP ‘creative explosion’ illustrates the attempt to counter cognitive losses inherent in cumulative cultural evolution and incipient self-domestication.
Unfortunately, by considering the cumulative type of cultural evolution as the ‘natural choice’ of all cognitively modern humans, gene-culture coevolution theory implies that the ‘ratcheting’ of innovations is the only index of ‘progress.’ In the modelling of the theory the stress is placed on social complexity, the absence of which would render small and isolated populations vulnerable to the ‘treadmill effect,’ the inevitable consequence of impaired social learning. However, the anthropological literature documents isolated hunter-gatherer groups that have developed intricate exchange networks that do not necessarily rely on technological innovation and function only in low demographic settings. Not only that the biases upon which transmission depends in cumulative cultural evolution—prestige, skills, success—are unknown, but certain ‘leveling mechanisms’ inhibit these very parameters and thus, no cultural models can rise to prominence. Contrary to the predictions of the theory, these societies do not seem to be plagued by cultural ‘loss’ and, instead of hopelessly running the treadmill and living in poverty, they have developed egalitarian and, to an extent, ‘affluent’ societies.
Populations following a non-cumulative type of cultural evolution—known in anthropology as ‘immediate-return’ hunters-gatherers—are often described as ‘pedomorphic,’ due to their markedly neotenous morphological features and cognitive attitudes. On the other hand, populations that follow a cumulative type of cultural evolution are surprisingly ‘robust’ phenotypes. In the case of the latter, a cultural ‘sudden jump’ seems to have occurred during the Late Pleistocene which, in its turn, resulted in the entrenchment of archaic behavioral traits and the
establishment of hierarchical societies. Conversely, with certain isolated hunters-gatherers, a cultural ‘regression’ seems to have taken place during the Early Holocene. The adoption of a cultural ‘primitivism’—immediate-return subsistence—offered a degree of evolutionary flexibility that allowed for a neotenal leap. This, in its turn, enabled
the reduction of archaic behavioral traits and the emergence of egalitarian societies.