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2020-12-26 15:23:23   •   ID: 2227

Archaic Handaxe from Sterkfontein - South Africa

Figure 1
Figure 1 and 2: These are two different views from the complex cave system of Sterkfontein in South Africa (GNU Free Documentation License; Wikipedia)

Figure 3, 4 and 5 show a very early Pick-like Acheulian non-stratified Handaxe, found from Sterkfontein.

The Handaxe ist 12 cm long and made from a thick (up to 4,5 cm) large Flake (LCT). It is made of hard and very homogeneous Chert and is heavily patinated and rolled. It has a zig-zag cutting edge on one side and a coarsely retouched back on the other.

It reveals a triangular cross-section with a plain ventral side and high angled two dorsal sides. Minimal cortex remains are still present.

Sterkfontein is one of the many caves with a long Geological and Scientific history -part of the "Cradle of Humankind" in South Africa.

The so called "Cradle of Humankind" is located about 50 km N/W of Johannesburg, South Africa, in the Gauteng province.

It is huge accumulation of underground Paleoanthropological and Prehistoric sites, comparable in the importance only with the famous Plio-Pleistocene sites of East Africa.

Figure 2
Declared a World Heritage site by UNESCO in 1999, the Region of Interest currently occupies about 47000 hectares and contains a complex succession of limestone caves with late Plio - early Pleistocene infill.

Of interest for Aggsbachs Blog are the following caves bearing remains of different Hominins and ESA-MSA artifacts, as well as well preserved faunal remains.

Dating was performed by faunal remains, Uranium–Lead dating and paleomagnetic stratigraphy. Because these methods sometimes gave conflicting results, Cosmogenic nuclide burial dating has introduced in the repertoire during the last years- sometimes with astonishing results

  • Sterkfontein: several remains of Australopithecus africanus; Australopithecus Prometheus, early Homo sp.
  • Kromdraai: Paranthropus robustus, Early Homo sp.
  • Swartkrans: Paranthropus robustus, Homo Ergaster
  • Cooper’s Caves: Paranthropus robustus
  • Drimolen: several remains of Paranthropus robustus , early Homo sp.
  • Gondolin: Paranthropus robustus
  • Gladysvale: Australopithecus Africanus
  • Malapa: Australopithecus Sebida
  • Makapanskat: Australopithecus Prometheus
  • Rising Star Cave: Homo naledi; Age: 236 - 335 k.a.

Figure 3
An excellent review about the Paleoanthropological record of the Gauteng Area can be found here: Review S-Africa .

Please note that the mentioned Hominins lived sympatric, in the same territory and during overlapping time periods, except Homo naledi from the Middle Pleistocene. We will here focus on the South African Paleoanthropological record.

Australopithecus most probably evolved in eastern Africa around 4,2 million years ago before spreading throughout East and South Africa and eventually became extinct 1,9 million years ago (or 1,2 million years ago if Paranthropus is included).

Australopithecus was an early ancestor of modern humans, was much smaller than us, and walked upright, but was probably unable to make tools.

Homo habilis is a species of archaic humans, unfortunately with a more fragmentary skeletal record, being present during the Early Pleistocene of East and South Africa and around 2,3–1,65 Ma.

The taxon remains highly controversial, with some researchers classify the findings as Australopithecus africanus, while others have proposed that Homo habilis is a valid taxon with an almost doubled brain volume of around 800 ccm compared with Australopithecus and was directly evolving into Homo ergaster.

Homo ergaster, appeared around 1,5 Ma and was the first of our ancestors to look more like modern humans. These people were generally tall and slender and had the evolutionary advantage of beeing long distance runners.
Figure 4
Some Palaeoanthropologists prefer to use the term African Homo erectus.

Interestingly the Asian Homo Erectus persisted in South Asia at the Solo River until early MIS 5 - pretty late after its disappearance in Africa.

Sterkfontein is a breccia-filled Dolomitic cave. Dolomite is thought to form by postdepositional alteration of limestone by magnesium-rich groundwater.

Dolomite, just like all the other types of rocks, became fractured due to forces from within the earth-crust.

Faults are geological fractures or cracks. Although dolomite is a pretty solid type of rock, these weaker fault zones in the dolomite provide access for water to penetrate deeper into the rock.

Under natural conditions, rainwater is slightly acidic because of the presence of dissolved carbon dioxide. Dolomite is vulnerable to acidic water. When the slightly acidic water seeps into cracks and fractures in the dolomite, it dissolves small amounts of rock.

Over time natural cracks could open up into larger cracks, allowing greater flow, which increases the dissolving of dolomite. Finally the cracks turn into veritable caves.

Figure 5
Sterkfontein is partly filled with overlapping layers of fossiliferous breccia that entered through multiple openings to the surface.

The infill was originally divided into six members thought to be in stratigraphic order, with Members 1–3 inside the cave and 4–6 now exposed at the surface owing to erosion of the cave roof (Granger et al. 2015).

Sterkfontein is of special interest in the context of the "Cradle of Humankind" because:

  • it bears the largest sample of Australopithecus s.s. (A. Africanus, A. Prometheus) fossils at one site. Furthermore Member 5 contains both Homo ergaster and Paranthropus remains)

  • the only known virtually complete Australopithecus skeleton “Little Foot” (StW 573) was found her. It has been described as Australopithecus Prometheus

  • Cosmogenic isochrone nuclide burial dating showed that the breccia containing StW 573 did not undergo significant reworking, and was deposited 3.67 ± 0.16 million years ago. Functionally, the bones suggest that these hominins may have retained tree-climbing abilities far beyond what later humans had. In addition, AtW 573 is coeval with the (more primitive?) Australopithecus afarensis in eastern Africa (Granger et al. 2015)

  • it bears in Member 5 a representative Oldowan industry, largely in a near-primary context with more than 3500 artifacts, mainly made of Quartz and dated to to 2,18 ± 0.21 Ma.

  • The Oldowan of Member 5 is followed by an Archaic Acheulian. Only one late Acheulian handaxe has been found, and the infill in Member 5 is partially contaminated with MSA artifacts, which can be easily diagnosed by their morphology and characteristic surface staining

  • Burned bones from Swartkrans Cave in South Africa suggest that hominids system- atically used fire beginning 1.0 to 1.5 Ma

  • The early Acheulean (Member 5 West), is dated to 1,7-1,4 Ma. Anyhow a new dating program revealed a date of 1,84 Ma (Granger 2015). This date would make Sterkfontein the oldest Acheulian in South Africa (Kuman 1998; Kuman et al. 2005)

  • Member 5 both contained early Homo (Habilis or Ergaster) and in addition Paranthropus skeletal remains.

    Anyhow, the makers of the Oldowan and the Early Acheulian remain unknown, although it is generally believed that early Homo was the Author of the Acheulian, while the question if Australopithecus / Paranthropus was able to produce the Oldowan remains open for further discussion.

    Anyhow, an archaic Mode-I industry incorporated in sediments about 3.3 million years old is known from Lomekwi in Kenya long before the advent of the genus Homo. Current paradigms about first toolmakers will probably have to be reconsidered....

Kuman (1994 and later) has described the early Acheulian from Sterkfontein. Only parts of it come from in-situ context. Compared with the small sized Quartz-rich Oldowan, Chert and Quartzite were more common for tool production.

Small Flakes were rare, compared to the Oldowan and larger tools prevail. Cleaver were produced by the LCT technique, while simple Handaxes were made from larger Flakes or from cobbles.

Handaxes from a secure in-situ context clearly resemble the non-stratified piece, shown in this post.

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