Sort order:  

Status: 1 Treffer   •   Seite 1 von 1   •   10 Artikel pro Seite

2018-11-08 15:28:32   •   ID: 2048

Erg Issaouane / Algeria and the changing views on the African Neolithic

Fig.1
The Issaouane Erg (also called Issaouane-N-Irrararene) is a sand sea, covering approximately 38,000 km2 in Algeria's South East and part of the Sahara desert.

Erg Issaouane is situated east of the northern outposts of the Tassili n'Ajjer and finds its continuation in the Ubari sand sea, already introduced in this blog- see here 2002 , flanked by the Libyan erg of Murzuq.

NASA's Earth Observatory notes that three types of erg dunes, displayed in Figure 1 (NASA public domaine) exist at Erg Issaouane:

"The most common landforms in the image are star dunes and barchan (or crescent) dunes. Small linear dunes appear at top left. Star dunes are formed when sand is transported from variable wind directions, whereas barchan dunes form in a single dominant wind regime. The superimposition of two dune types suggests that wind regimes have changed through time".

The formation of stationary mega dunes can take hundreds of thousands of years to form; mesoscale dunes form on the mega dunes over thousand of years and smaller ones may arise, which migrate over the bigger ones during very short time intervals.

Figure 2
Paleolithic findings from Erg Issaouane are rather rare. They were found as small isolated scatters of ESA / MSA artifacts similar to the richer findings in the Murzuq.

The "Neolithic" is much more common. It was never described monographically, while we have a good overview by Aumassip (see external links) about the "Bas Sahara" further North. Anyhow this account was published 32 years ago.

The Sahara underwent a major population increase between 10,5 and 5,5 K.a.BP. and the climatic amelioration seems to be the prime factor driving broad-scale population dynamics (Manning 2014).

Figure 3
Figure 2 shows a 13 cm long, flat bifacial artifact with oblique basis, similar to examples described from the Bas Sahara and quite different from MSA-foliates of the Sahara-as seen here: 2032 . The same holds true for the sickle like flat artifact , shown in Figure 3.

Grinding stones, top stones and pestles are scattered all over the surface of the Sahara together with the ubiquitous inventory of Neolithic sites: Polished axes, arrowheads, backed pieces and microliths.

Figure 4 shows an colorful topstone (108 x 73 x 44 mm), that was found in isolation at Erg Issaouane more than 40 years ago. It would have been used to grind grains for cooking or to grind other organic and inorganic material, like minerals to make pigments.

The the transitions between topstones and small zoo- and anthropomorphic carvings are fluid.

Such sculptures have been found in the Tassili n'Ajjer and the Admer Erg, but are also known from the Issaouane sand sea.

Figure 4
Camps wrote in 1982: "To date, some thirty-eight of these Neolithic animal sculptures from Tassili n'Ajjer, the Admer Erg and the Ahaggar are known and some anthropomorphic cult figurines from Tabelbalat, Issaouane and Ouan Sidi are included in this total.

They were found outside and to the north of the area of greatest concentration, made up of the Tassili n'Ajjer and the Admer Erg.

Among the animals represented, cattle are far more numerous than sheep, antelopes or rodents. They all observe quite strict stylistic rules, essentially based on bilateral symmetery on each side of an axis, usually marked by a crest which, on some of the sculptures, runs from the muzzle to the end of the back"
.

But back to the basic theme: what was the Saharan "Neolithic"?

Early Scholarly discussions about African agricultural origins were profoundly influenced by the implicit and poorly defined concept of the Neolithic ("The age of Polished stone") which, originally developed in Europe and the Middle East, was uncritically transmitted to Africa.

Figure 5
Outside Africa the Neolithic is defined by the use of domesticated plants, often followed by animal domesticates.

The equation of the Neolithic with plant production led to expectations that polished tools (Figure 5), ground-stones and pestles (Figure 4), and pottery in Africa should be associated with domestic plants.

But decennia of research (for example at Adrar Bous, Nabta Playa, Wadi Kubanniya) did not find early domesticates, but ironically produced one of the best documented evidence for an intensive use of of wild plants (wild grasses, legumes and tubers) by our ancestors.

These observations were recently been re-confirmed by Mercuri et all. for the Takarkori rock-shelter in southwest Libya.

Here extensive Archeobotanical finds indicate that, during the the Holocene green Sahara period, from 9500 to 5500 cal BP, encompassing foraging communities followed by Pastoralists, cultivation did not lead to domestication.

Figure 6
Interestingly, many of the remains were from species that we would consider "weedy" – invasive, opportunistic plants that people at the site would have cultivated and managed but never domesticated.

The use of such plants highlights their potential value as reliable food resources in the face of climate change and desertification and thus the successful adaption of Homo Sapiens to different habitats.

Figure 6 shows a plant, that later would become important as a domesticate in Africa: ''Sorghum bicolor'' from Leonhart Fuchs New Kreüterbuch; 1543. Basel.