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Engraved ochres and ostrich eggshells from the South African Blombos Cave and Diepkloof Rock Shelter are among the earliest expressions of human symbolic behavior. Furthermore, they appear to document a continuous practice of abstract mark-making across ~40.000 years. During this time, the engraved patterns change from simpler unstructured patterns to complex, ordered and symmetric cross-hatchings. To inform discussions of the possible function of the engravings, we conducted a two-part experimental study. Based on the assumption that the pragmatic use of an artifact will motivate incremental adaptive refinements, we used transmission chain experiments to reconstruct the original trajectory of changes. We then conducted five experiments to assess the cognitive implications of changes to the patterns and compared these to the original engravings. Although we observe interesting similarities, our findings suggest the Blombos and Diepkloof engravings are not only a product of human cognitive biases and constraints on working memory.

Dating back as far as 100 ka, the Blombos ochre and the Diepkloof ostrich egg engravings are considered among theearliest fossilized evidence of human symbolic behavior. Of special interest to this study is the temporal trajectory spanningmore than 30 thousand years from earlier simpler parallel line patterns to later complex cross-hatchings suggesting adaptivecompositional development. Through a series of three psychophysical experiments we test the hypotheses that the line engrav-ings at each site evolved to become 1) more salient to the human perceptual system, 2) more discriminable from each other, and3) increasingly associated with symbolic intent. Our findings suggest that just as instrumental tools have been found to undergocumulative refinements in adaptation to their function, the ochre and egg shell engravings evolved adaptively to become morefit for their cognitive function as signs.

The study of human remains can provide valuable information about aspects of past populations. Here we present an updated database consisting of 590 radiocarbon (14C) dates for human remains from Holocene South Africa before European contact. We calibrated or recalibrated all the previously published dates using the most recent calibration curve for the southern hemisphere. Each date is roughly georeferenced and plotted according to their Stone Age or Iron Age contexts, revealing the broad distribution pattern of dated Holocene human remains across South Africa—perhaps reflecting aspects of past population distribution and densities, but also underscoring historical collection practices, archaeological research focus, and preservation conditions. We use Kernel Density Estimation models to show peaks and troughs of dated remains through time, with Later Stone Age peaks at ∼5.5 ka cal BP, ∼2 ka cal BP and ∼0.5 ka cal BP, and Iron Age peaks ∼1.1 ka cal BP and ∼0.5 ka cal BP, some of which show broad correspondence to climatic data. Our data, based on dated remains only, do not provide a full reflection of past populations, and our large-scale, coarse-grained analysis cannot yet assess the reasons for the peaks in dated human remains in detail. Yet, the study provides a new resource, and a data-driven overview that highlights aspects to be explored with further contextual analyses against the available archaeological records, population histories and climatic indicators through time and across space. [ABSTRACT FROM AUTHOR]

So-called desert kites have been found widely in the Middle East and Central Asia. The newly discovered Keimoes 3 site in the Nama Karoo, however, represents one of only three known desert kite sites in southern Africa. The complex comprises 14 funnels arranged in three groups around a small hill. Radiocarbon dates for structures in the region suggest a relative age for the kites of less than 2000 years. The authors demonstrate how strategic use of the site's micro-topography optimised game harvesting, and argue that Keimoes 3 offers robust evidence of Holocene Stone Age hunters engaging in long-term landscape modification as part of their subsistence strategies. Keywords: southern Africa, Nama Karoo, Holocene, hunting strategies, desert kites, lidar, Introduction Desert kites, in a broad sense, comprise long, low stone walls arranged in V- or funnel-shaped 'arms' converging into tapering funnel 'necks', before sometimes ending on an enclosure known [...]