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The Halibee member of the Upper Dawaitoli Formation of Ethiopia's Middle Awash study area features a wealth of Middle and Later Stone Age (MSA and LSA) paleoanthropological resources in a succession of Pleistocene sediments. We introduce these artifacts and fossils, and determine their chronostratigraphic placement via a combination of established radioisotopic methods and a recently developed dating method applied to ostrich eggshell (OES). We apply the recently developed 230Th/U burial dating of OES to bridge the temporal gap between radiocarbon (14C) and 40Ar/39Ar ages for the MSA and provide 14C ages to constrain the younger LSA archaeology and fauna to ∼24 to 21.4 ka. Paired 14C and 230Th/U burial ages of OES agree at ∼31 ka for an older LSA locality, validating the newer method, and in turn supporting its application to stratigraphically underlying MSA occurrences previously constrained only by a maximum 40Ar/39Ar age. Associated fauna, flora, and Homo sapiens fossils are thereby now fixed between 106 ± 20 ka and 96.4 ± 1.6 ka (all errors 2σ). Additional 40Ar/39 results on an underlying tuff refine its age to 158.1 ± 11.0 ka, providing a more precise minimum age for MSA lithic artifacts, fauna, and H. sapiens fossils recovered ∼9 m below it. These results demonstrate how chronological control can be obtained in tectonically active and stratigraphically complex settings to precisely calibrate crucial evidence of technological, environmental, and evolutionary changes during the African Middle and Late Pleistocene.

This exhibition showcases the results of archaeological research at three coastal sites in the southern Cape of South Africa: Blombos Cave, Klipdrift Shelter and Klasies River main sites. Part of [...]

Zooarchaeologists have long relied on linear traces and pits found on the surfaces of ancient bones to infer ancient hominid behaviors such as slicing, chopping, and percussive actions during butchery of mammal carcasses. However, such claims about Plio-Pleistocene hominids rely mostly on very small assemblages of bony remains. Furthermore, recent experiments on trampling animals and biting crocodiles have shown each to be capable of producing mimics of such marks. This equifinality-the creation of similar products by different processes-makes deciphering early archaeological bone assemblages difficult. Bone modifications among Ethiopian Plio-Pleistocene hominid and faunal remains at Asa Issie, Maka, Hadar, and Bouri were reassessed in light of these findings. The results show that crocodiles were important modifiers of these bone assemblages. The relative roles of hominids, mammalian carnivores, and crocodiles in the formation of Oldowan zooarchaeological assemblages will only be accurately revealed by better bounding equifinality. Critical analysis within a consilience-based approach is identified as the pathway forward. More experimental studies and increased archaeological fieldwork aimed at generating adequate samples are now required.

Twenty-six Middle Stone Age obsidian artifacts from the Gademotta Formation were instrumentally characterized by energy dispersive X-ray fluorescence. Analysis of artifacts from the type locality enabled sampling of a greater time depth while avoiding the uncertainties in previous results on artifacts sampled from a 'disturbed' context at Kulkuletti. Moreover, the analysis here of source samples from Alutu, Worja, and the previously unstudied Bora and Ficke sources in the broader region offers a better understanding of prehistoric lithic raw material procurement. The local Worja source, an aphyric obsidian excellent for tool production, substantially dominates the assemblage. Bora, another aphyric obsidian in the wider region, is also present, but not common. The vitrophyric Ficke and Alutu obsidian sources with abundant sanidine phenocrysts were not present in the archaeological assemblage, and likely did not compete with Worja and Bora for tool production. At least one artifact appears to be from an as yet unknown source, thus confirming results of previous studies. A few artifacts share similar geochemical composition with the Worja and Bora sources, thus highlighting the complexity of obsidian source studies in this part of the rift where multiple geographically close sources may share similar crustal material. [ABSTRACT FROM AUTHOR]