These rock engravings, together with those found in more northerly regions, bear witness to wide-spread phenomena which cannot be detected by archaeological digs : the mobility of pastoralists during early Neolithic, the transmission of ideas and of luxury goods over long distances at the beginning of the Metal age, Touaregs settling in the south of the Sahara as from the IVth century A.D. Furthermore, several particular representations of metallic objects in the Adrar des Iforas region seem to indicate the presence of local metallurgical production as from the IInd Millenium B.C. for which archaeological excavations may be able to discover remains. And furthermore, hundreds of representations of armed warriors with spears show the hierarchical organisation of society during the Ist Millenium B.C., which would seem to correlate with what we already know about the political organisation and defense strategies present in different West African regions at this time.
