The Emergence of Habitual Ochre Use in Africa and its Significance for The Development of Ritual Behavior During The Middle Stone Age

Over the last two decades, red ochre has played a pivotal role in discussions about the cognitive and cultural evolution of early modern humans during the African Middle Stone Age. Given the importance of ochre for the scholarly debate about the emergence of ‘behavioral modernity’, the lack of long-term spatio-temporal analyses spanning large geographical areas represents a significant gap in knowledge. Here we take a continent-wide approach, rather than focusing on specific sites, regions or technocomplexes. We report the most comprehensive meta-analysis of ochre use to date, spanning Africa between 500 and 40 thousand years ago, to examine data from more than a hundred archaeological sites. Using methods based on time averaging, we identified three distinct phases of ochre use: the initial phase occurred from 500,000 to 330,000; the emergent phase from 330,000 to 160,000; and the habitual phase from 160,000 to 40,000 years ago. The number of sites with ochre increased with each subsequent phase. More importantly, the ratio of sites with ochre compared to those with only stone artifacts also followed this trend, indicating the increasing intensity of ochre use during the Middle Stone Age. While the geographical distribution expanded with time, the absolute number of ochre finds grew significantly as well, underlining the intensification of ochre use. We determine that ochre use established itself as a habitual cultural practice in southern, eastern and northern Africa starting about 160,000 years ago, when a third of archaeological sites contain ochre. We argue that this pattern is a likely material manifestation of intensifying ritual activity in early populations of Homo sapiens . Such ritual behavior may have facilitated the demographic expansion of early modern humans, first within and eventually beyond the African continent. We discuss the implications of our findings on two models of ritual evolution, the Female Cosmetic Coalitions Hypothesis and the Ecological Stress Hypothesis, as well as a model about the emergence of complex cultural capacities, the Eight-Grade Model for the Evolution and Expansion of Cultural Capacities .