Rock art revisited.

Abstract

Two pieces of engraved red ochre from Blombos Cave, South Africa, dating to 77,000 years ago and displaying “motifs” evidencing the existence of “arbitrary conventions unrelated to reality-based cognition” are reported by Henshilwood et al. (“Emergence of modern human behavior: Middle Stone Age engravings from South Africa,” Reports, 15 Feb., p. [1278][1]). We propose the following hypothesis as an alternative to that presented by Henshilwood et al. : that the Blombos Cave engraved ochres represent small, portable objects upon which reality-based tallies were recorded. Three lines of evidence support this hypothesis: (i) the worn condition of the ochre objects, (ii) duplications of lines consistent with erasure and reuse, and (iii) the sequence in which lines were engraved. First, both the SAM-AA 8937 and 8938 pieces exhibit irregular surfaces blemished by pits and scrapes. Although it may be that preparing surfaces and engraving resulted in objects that look worn, it is also plausible to suggest that a utilitarian function produced a worn appearance. Second, the occurrence of duplicate parallel lines is consistent with active use and reuse. We suggest that such lines were caused by reuse after incomplete erasure by grinding rather than simultaneous scoring occasioned by a change in position of the engraving tool. Finally, the sequence of engraving, wherein a series of lines was first engraved in one direction and then sequentially cross-hatched, suggests that the lines may have served a utilitarian recording or counting function. We consider the evidence equivocal as to the nature of the symbolic content of the engraved ochre pieces. Perhaps they reflect cognitive shifts facilitating both art and science. Whether motifs, tallies, or yet some other alternative, the patterns on the engraved ochre provide a fleeting glimpse into the minds of those inhabiting Africa some 35,000 years before the beginning of the Upper Paleolithic. Modern minds should remain open to the range of cognitive possibilities represented by these enigmatic data. [1]: /lookup/doi/10.1126/science.1067575