2018-11-08 15:28:32 • ID: 2048
Erg Issaouane / Algeria and the changing views on the African Neolithic
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 2129 , 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.
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).
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.
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.
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 any proof of 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.
The use of such plants highlights their potential value as reliable food resources in the face of climate change and desertification and thus one of the many ways of 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.
Resources and images in full resolution:
- Image: 2018-11-08_issaouane.jpg
- Image: 2018-11-08_duo11.jpg
- Image: 2018-11-09_small_celts_algeria.jpg
- Image: 2018-11-09_Welscher_Hirss_Fuchs_1543_760.jpg
- Image: 2018-11-30_issaouane.jpg
- Extern Link: www.persee.fr…etaf_0768-2352_1986_mon_1_1
- Extern Link: ls-tlss.ucl.ac.uk…ARCLG202_54728.pdf
- Extern Link: www.nature.com…s41477-017-0098-1
- Extern Link: www.sciencedirect.com…S0277379114002728