Sibudu Cave

Sibudu Cave is a cave in a sandstone cliff in northern KwaZulu-Natal, South Africa.^[1] It is an important Middle Stone Age site occupied, with some gaps, from 77,000 years ago to 38,000 years ago. In it, evidence has been found of some of the earliest examples of modern human technology, including the earliest bone arrow (61ka ago),^[2] the earliest needle (61 ka ago),^[2] and the earliest use of heat treated mixed compound gluing (72 ka ago).^[2] The glues are of particular interest, because the complexity of their creation and processing has been presented as evidence of continuity between modern human cognition and that of early humans.^[3][4]

Contents 1 Description 2 Occupation 3 Technology 4 Cognitive archeology 5 Interrupted technological development 6 See also 7 References 8 External links

[edit] Description

The cave is a rock shelter, located roughly 40 km (25 mi) north of the city of Durban and about 15 km (9 mi) inland, near the town of Tongaat. It is in a steep, forested cliff facing WSW that overlooks the Tongati River in an area that is presently a sugar cane plantation. The cave was formed by downcutting of the Tongati River, which now lies 10 m (33 ft) below the cave. The cavern floor is 55 m (180 ft) long, and about 18 m (59 ft) in width.^[1] It has a large collection of Middle Stone Age deposits that are well preserved organically and accurately dated using optically stimulated luminescence.^[1]

The first excavations following its discovery in 1983 were carried out by Aron Mazel of the Natal Museum (unpublished work).^[5] Lyn Wadley of the University of the Witwatersrand started renewed excavations in September 1998.

Various examples of early human technology have been found:

• A bone arrow that pushes back the origin of bow and bone arrow technology by at least 20,000 years beyond the previous earliest example, to 61,000 BP.^[2];
• The earliest known bone needle, dated to 61,000 BP, with wear similar to that found in bone needles used to puncture animal hide.^[2];
• The earliest example of a compound glue (plant gum and red ochre), used for hafting stone points into wood handles to create spears—-dated no later than 71,000 BP.^[2]; and
• Shell beads, though of a more recent date than those found at Blombos cave (71,000 BP for the Sibudu beads, versus 75,000 BP for those at Blombos).^[6][7]

[edit] Occupation

The occupations at Sibudu are divided into pre-Still Bay, Still Bay (72,000-71,000 BP), Howiesons Poort (before 61,000 BP), post-Howiesons Poort (58,500 BP) and late (47,700 BP) and final Middle Stone Age phases (38,600 BP). There were occupation gaps of around 10,000 years between the post-Howiesons Poort and the late Middle Stone Age stage, and the late and final Middle Stone periods. There was no Stone Age occupation, though there was a 1,000 BP Iron Age occupation.

Evidence suggests these were dry periods and the cave was only occupied during wet climatic conditions.^[8]

[edit] Technology

The pre-Still Bay occupation had a lithic flake-based industry and made few tools. The Still Bay, in addition to such flakes, made bifacial tools and points .^[9] Trace use analysis on the tips of the points finds evidence of compound adhesives on their bases where they would once have been hafted to shafts.^[10]

Howiesons Poort occupation manufactured blade tools. These blades are shaped like the segment of an orange, with a sharp cutting edge on the straight lateral and an intentionally blunted and curved back. These were attached to shafts or handles by means of ochre and plant adhesive or alternatively fat mixed with plant material.^[3] Segments were often made with a cutting edge along their entire length which requires that they be attached to their hafts without twine and so requiring particularly strong adhesive glue.^[11]

Points were used in the period after the Howiesons Poort for hunting weapons such as the tips of spears. Use–trace analysis suggests that many of these points were hafted with ochre-loaded adhesives.^[11]

[edit] Cognitive archeology

The replication of shafted tool manufacture using only methods and materials available at Sibudu has enabled the identification of the complexity of the mental thought processes that it required. The stone spear was embedded in the wood using a compound adhesive made up of plant gum, red ochre, and to aid the workability, possibly a small amount of beeswax, coarse particles or fat.^[3] This preliminary mixture had to have the right ingredient proportions and then before shafting with a controlled heat treatment stage. This heating had to avoid boiling or dehydrating the mixture too much otherwise it would weaken the resulting mastic. Also the maker had to reduce its acidity. Researchers by experimentally recreating the creation of the adhesive concluded that the capacity for do this by Middle Stone Age (MSA) humans at Sibudu would have required the multilevel mental operations and abstract thought of modern people.^[3][4]

Artisans living in the MSA must have been able to think in abstract terms about properties of plant gums and natural iron products, even though they lacked empirical means for gauging them. Qualities of gum, such as wet, sticky, and viscous, were mentally abstracted, and these meanings counterpoised against ochre properties, such as dry, loose, and dehydrating. Simultaneously, the artisan had to think about the correct position for placing stone inserts on the shafts. ... Although fully modern behavior is presently recognizable relatively late in the MSA, the circumstantial evidence provided here implies that people who made compound adhesives in the MSA shared at least some advanced behaviors with their modern successors.^{[3]p. 9593.}

In a commentary upon this research it has been suggested that instead of focusing upon language, that with

activities that tax reasoning ability and are also visible archaeologically, such as shafting, archaeologists are in a better position to contribute to an understanding of the evolution of the modern mind.^{[4]p. 9545.}

[edit] Interrupted technological development

Artifacts such as piecing needles, arrows, shell beads^[6] at Sibudu and elsewhere occurs in a pattern whereby innovations are not further and progressively developed but arise and then disappear. For instance the shell beads occur in the Still bay layers but are absent from the Howiesons Poort ones in Sibudu and elsewhere.^[6] This questions the idea that the early development of technology by early humans was a process of accumulation of improvements.^[2][6] In discussing the findings of artifacts at Sibudu researchers have commented that they :

can hardly be used to support the ‘‘classic’’ out of Africa scenario, which predicts increasing complexity and accretion of innovations during the MSA, determined by biological change. Instead, they appear, disappear and re-appear in a way that best fits a scenario in which historical contingencies and environmental rather than cognitive changes are seen as main drivers.^{[2]p. 1577.}

The idea that environmental change was responsible for this pattern has been questioned and instead it has been suggested the driving factors were changes in the social networks related to changes in population density.^[12]

[edit] See also

• Howieson's Poort Shelter
• Klasies River Caves
• List of caves in South Africa
• Modern behaviour
• Timeline of evolution
• Timeline of historic inventions

[edit] References

[edit] External links

• Little arrow that rewrites history books
• Sibudu Cave (South Africa)