May 02, 2013

Small-bodied humans from the Terminal Pleistocene in Tanzania

East Africa is known for the tall and lean physiques of many of its current inhabitants, but there has been speculation -on linguistic or other grounds- that it was once home to people similar to the present-day Bushmen of southern Africa. A new publication on small-bodied humans from Tanzania may be related to this hypothesis.

From the paper:
New discoveries, such as B-1 from Mlambalasi, may renew discussion on the presence of small-bodied people in East Africa. Based on the few comparable skeletal samples, this individual does not conform to the typical tall, robust, and linear body proportions of previously reported East African LSA populations. Instead, itssmall body size has more in common with southern African peoples. This does not necessarily imply a biological link between these LSA populations. Hypotheses for why small size develops include the need for thermoregulation, limited food supply, enhanced mobility, and high mortality influencing early reproduction (Perry and Dominy, 2009; Pfeiffer and Harrington, 2011). In southern Africa, small body size may be linked to energetics and accident avoidance. The rate of injury among the South African LSA populations is lower than other mobile hunter-gatherer groups, which Pfeiffer (2007) interprets as possibly related to reduced body mass. Ethnographic studies of modern Khoesan emphasize the centrality of the bow and arrow and persistence hunting, in which small, energetically efficient bodies prove advantageous (Tobias, 1978). Small body size may have emerged multiple times, perhaps amidst the low population densities and climatic instability of the LSA. Given that early modern humans may have endured a population crisis (Harpending et al., 1993; Ambrose, 1998a; Lahr and Foley, 1998; Reich and Goldstein, 1998), and that there is some evidence for increased diversity among earlier populations (Crevecoeur et al., 2009), one characteristic of some terminal Pleistocene and early Holocene groups may have been a small body size. Exploring the incidence of scope of this pattern in East African and other early modern humans may shed light on the importance of body size in human evolution.

International Journal of Osteoarchaeology DOI: 10.1002/oa.2323

Terminal Pleistocene Later Stone Age Human Remains from the Mlambalasi Rock Shelter, Iringa Region, Southern Tanzania†

E. A. Sawchuk1, P. R. Willoughby

This paper introduces research at the Mlambalasi rock shelter in the Iringa Region of southern Tanzania. The deposits are composed of a historic and Iron Age occupation, a microlithic Holocene Later Stone Age (LSA), and then a macrolithic Late Pleistocene LSA. Middle Stone Age deposits are also present on the slope in front of the rock shelter. Excavations in A.D. 2002, 2006, and 2010 yielded fragmentary human remains as well as pottery, iron, stone tools, faunal bone, and glass and ostrich eggshell beads. Among the human remains, four individuals are present: two adults and a juvenile were found in the same LSA context, and another adult associated with the Iron Age/historic period. The most complete skeleton is an adult of indeterminate sex that was found in situ in an LSA deposit. Charcoal in proximity to the bone was AMS radiocarbon dated to 12,925 cal BC (OxA-24620), which is consistent with radiocarbon dates on giant land snail shells from above and below the remains. The skeleton exhibits a series of pathological changes such as extensive dental wear and carious lesions, as well as damage most likely caused by termites, post-mortem. The most striking aspect of this individual is its small size; stature and body mass estimations place it in the range of historic Khoesan from southern Africa. Consequently, this research adds to the discourse regarding the existence of small-bodied people in the East African LSA. Findings from this new skeletal sample will contribute to studies of human biology and variation in Africa during the terminal Pleistocene and Holocene. This article is protected by copyright. All rights reserved.


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