Saharan rock painting. Rock art depicting human figures, one of which is sitting on a horse, surrounded by a herd of horned animals. The rock art of the Sahara reflects both the change in climate and cultural advance of the humans who inhabited the region since the last ice age. Horses appear in Saharan rock art from around 3,000 years before present, during a period of increased aridity in the Sahara. Photographed in Algeria.