The rock formation is an archaeological site, noted for its numerous prehistoricparietal works of rock art, first reported in 1910, that date to the early Neolithic era at the end of the last glacial period during which the Sahara was a habitable savanna rather than the current desert. Although sources vary considerably, the earliest pieces of art are presumed to be 12,000 years old. The vast majority date to the ninth and tenth millenniaBP or younger, according to OSL dating of associated sediments. Among the 15,000 engravings so far identified, the subjects depicted are large wild animals including antelopes and crocodiles, cattle herds, and humans who engage in activities such as hunting and dancing. According to UNESCO, "The exceptional density of paintings and engravings...have made Tassili world famous."
Geography
Tassili n'Ajjer is a vast plateau in southeastern Algeria at the borders of Libya, Niger, and Mali, covering an area of 72,000 km2. It ranges from east-south-east to. Its highest point is the Adrar Afao that peaks at, located at. The nearest town is Djanet, situated approximately southwest of Tassili n'Ajjer. The archaeological site has been designated a national park, a Biosphere Reserve and was induced into the UNESCO World Heritage Site list as Tassili n'Ajjer National Park. The plateau is of great geological and aesthetic interest. Its panorama of geological formations of rock forests, composed of eroded sandstone, resembles a lunar landscape.
Geology
The range is composed largely of sandstone. The sandstone is stained by a thin outer layer of deposited metallic oxides that color the rock formations variously from near-black to dull red. Erosion in the area has resulted in nearly 300 natural rock arches being formed, along with many other spectacular land formations.
Ecology
Because of the altitude and the water-holding properties of the sandstone, the vegetation here is somewhat richer than in the surrounding desert. It includes a very scattered woodland of the endangeredendemic species of Saharan cypress and Saharan myrtle in the higher eastern half of the range. The ecology of the Tassili n'Ajjer is more fully described in the article West Saharan montane xeric woodlands, the ecoregion to which this area belongs. The literal English translation of Tassili n'Ajjer is 'plateau of rivers'. Relict populations of the West African crocodile persisted in the Tassili n'Ajjer until the twentieth century. Various other fauna still reside on the plateau, including Barbary sheep, the only surviving type of the larger mammals depicted in the rock paintings of the area.
Fungoid rock art
In 1989, the psychedelics researcher Giorgio Samorini exposed the theory that the fungoid-like paintings in the caves of Tassili are proof of the relationship between humans and psychedelics in the ancient populations of the Sahara, when it was still a wild green land: This theory was reused by Terence McKenna in his 1992 book Food of the Gods, hypothesizing that the Neolithic culture that inhabited the site used psilocybin mushrooms as part of its religious ritual life, citing rock paintings showing persons holding mushroom-like objects in their hands, as well as mushrooms growing from their bodies. For Henri Lohte who discovered the Tassili caves in the late 1950s, these were obviously secret sanctuaries. The painting that best backs the mushroom hypothesis is the Tassili mushroom figure Matalem-Amazar where the body of the represented shaman is covered with mushrooms. According to Earl Lee in his book From the Bodies of the Gods: Psychoactive Plants and the Cults of the Dead, this imagery refers to an ancient episode where a "mushroom shaman" was buried while fully-clothed and when unearthed some time later, tiny mushrooms would be growing on the clothes. Earl Lee considered the mushroom paintings at Tassili fairly realistic. According to Brian Akers, writer of the Mushroom journal, the fungoid rock art in Tassili does not resemble the representations of the Psilocybe hispanica in the Selva Pascuala caves. The art at Tassili is not even considered realistic.
