I first read that the Sahara desert was once a lush, verdant landscape in Joel Salatin’s book “Salad Bar Beef” but I wasn’t aware of any papers from the scientific literature which supported this. Here are a couple … the mainstream science writers differ somewhat on their timeframe from mine … I would place a “green Sahara” back only about 3500 – 4500 years ago, that is, sometime after the Flood of Noah. As for Joel’s claim that the Sahara region became a desert because of tillage and bad grazing management, I happen to buy his theory, but I am not aware of any mainstream science papers which support this thesis … but I bet some will pop up. I am interested in the possibility of re-greening deserts including the Sahara Desert and I am told by the leading practitioners of Mob Grazing that it is possible if Mob Grazing is adopted around the margins of the desert and moves inward.
Quaternary Science Reviews 19 (2000) 347}361
Abrupt onset and termination of the African Humid Period:
rapid climate responses to gradual insolation forcing
Peter deMenocal!,*, Joseph Ortiz!, Tom Guilderson”, Jess Adkins!, Michael Sarnthein#,
Linda Baker!, Martha Yarusinsky!
!Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
“Center for Accelerator Mass Spectrometry, Lawrence-Livermore National Laboratory, Livermore CA 94551, USA
#Institute Fuer Geowissens Chafter, Universitaet Kiel, Kiel, Germany
During the latest Pleistocene and early Holocene, the now hyperarid Saharan desert was a verdant landscape nearly completely vegetated with annual grasses and shrubs (COHMAP Members, 1988; Jolly, 1998; Sarnthein, 1978). At that time, subtropical North Africa was characterized by numerous large and small lakes which supported abundant savannah and lake margin fauna such as antelope, gira!e, elephant, hippopotamus, crocodile, and human populations in regions that today have almost no measurable precipitation (McIntosh and McIntosh, 1983). The Holocene African Humid Period occurred between ca. 9 and 6 cal. ka BP (Ritchie et al., 1985; Roberts, 1998), but humid conditions had initially commenced by ca. 14.5 cal. ka BP following full glacial hyperarid conditions during the latest Pleistocene (CO- HMAP Members, 1988; Street and Grove, 1979; Street-Perrot, et al., 1990; Sarnthein et al., 1982). LINK TO FULL ARTICLE
First dairying in green Saharan Africa in the fifth millennium BC
Julie Dunne, Richard P. Evershed, Mélanie Salque, Lucy Cramp, Silvia Bruni, Kathleen Ryan, Stefano Biagetti & Savino di Lernia
Nature 486, 390–394 (21 June 2012) doi:10.1038/nature11186
Received 16 March 2012 Accepted 08 May 2012 Published online 20 June 2012
In the prehistoric green Sahara of Holocene North Africa—in contrast to the Neolithic of Europe and Eurasia—a reliance on cattle, sheep and goats emerged as a stable and widespread way of life, long before the first evidence for domesticated plants or settled village farming communities1, 2, 3. The remarkable rock art found widely across the region depicts cattle herding among early Saharan pastoral groups, and includes rare scenes of milking; however, these images can rarely be reliably dated4. Although the faunal evidence provides further confirmation of the importance of cattle and other domesticates5, the scarcity of cattle bones makes it impossible to ascertain herd structures via kill-off patterns, thereby precluding interpretations of whether dairying was practiced. Because pottery production begins early in northern Africa6 the potential exists to investigate diet and subsistence practices using molecular and isotopic analyses of absorbed food residues7. This approach has been successful in determining the chronology of dairying beginning in the ‘Fertile Crescent’ of the Near East and its spread across Europe8, 9, 10, 11. Here we report the first unequivocal chemical evidence, based on the δ13C and Δ13C values of the major alkanoic acids of milk fat, for the adoption of dairying practices by prehistoric Saharan African people in the fifth millennium BC. Interpretations are supported by a new database of modern ruminant animal fats collected from Africa. These findings confirm the importance of ‘lifetime products’, such as milk, in early Saharan pastoralism, and provide an evolutionary context for the emergence of lactase persistence in Africa. LINK TO ABSTRACT