2018-08-28 18:35:40 • ID: 2021
The ESA-MSA Mosaic in East Africa
This is a large and thin (11x6x0,7 mm) convergent tool ("Point") with lateral semi-abrupt retouches and a thinned base made from a greenish ignimbrite, found decennia ago in Kenya. It is a classic MSA lithic tool, allthough the raw material was pretty exotic.
During the Oldowan and Acheulian of East Africa most artifacts are made of volcanic rocks like basalt, rhyolites, obsidian and ignimbrites (Welded tuff).
During the MSA, Ignimbrite becomes very rare, but was for unknown reasons occasionally preferred for single artifacts (for example at Porc Epic cave, Dire Dawa (east-central Ethiopia)- see also: 1450 .
Between 500 k.a. and 300 k.a. BP we notice large technological shifts in East Africa:
- The late Acheulian, as recently shown at the Hugub site in N-Ethiopia shows an increase of smaller Handaxes- some of them have already the appearance of bifacial MSA-Points, a decrease in Cleaver production, and evidence of intensive use of resharpening techniques. This was taken by the excavators as proof of a higher rate of curation and longer tool life, compared to earlier Acheulean ensembles. Interestingly the dates for the latest Acheulean in East Africa from Ethiopia and Eritrea were reported to be 160- 125 k.a. BP- and therfore much later, than the MSA was fully established elsewhere in the region.
- The earliest MSA- here defined as absence of LCTs and the use of prepared core techniques- developed side by side with the Acheulian. In the Kapthurin formation (Kenya), Blades, Levallois debitage, grindstones, and traces of pigment are found at site GnJh-15.
At the Acheulian site of GnJh-03, large Levallois flakes from centripetally cores where produced and sometimes retouched into handaxes or scrapers. Blade tools also co-occur with this industry. LHA/GnJh-03 is dated to 545-509 k.a. ,thus preceding anatomical modernity in hominins.
New excavations since 2001 at Olorgesailie revealed a similar picture: Acheulean occupations were followed by a long sequence of Middle Stone Age occupations without handaxes, beginning well before 315 k. a and ending before 64 k.a. Levallois technology was present already in the later Acheulean horizons of Members 11 and 13 of the Olorgesailie formation (between 625 and 550 k.a).
- After 300 k.a. BP, the East African MSA is already fully developed. Lithics are characterized by points with unifacial and bifacial retouch on non-Levallois and Levallois blanks, partially made from "Classic”, but also from "Nubian "cores. This is for example the the case at Gademotta (ETH-72-8B before 276±4 k.a BP; ETH-72-6 after 183±10 k.a BP) and at Kulkuletti (200–300 k.a BP)
Resources and images in full resolution:
- Image: 2018-08-28_msa_tuff.jpg
- Image: 2018-08-28_msa_tuffa.jpg
- Extern Link: in-africa.org…Clark-JD-et-al-1984-AAR-MSA-Porc-Epic.pdf
- Extern Link: www.researchgate.net…309812924_Archaeology_and_Context_of_Hugub_an_Important_New_Late_Acheulean_Locality_in_Ethiopia%27s_Northern_Rift
- Extern Link: core.ac.uk…19490338.pdf