Adrar des Ifoghas
He began his career in Africa with the study of monk seals on Mauritania's Cap Blanc peninsula. However, he soon turned his attention to the Sahara desert, which he would survey for more than sixty years in search of meteorites. Though he failed to find the meteorite he sought, he discovered numerous plant species as well as several important Neolithic sites. Perhaps his most important find (together with Wladimir Besnard) was the Asselar man, a 6,000-year-old skeleton of the Adrar des Ifoghas that many scholars believe to be the first remains of a distinctly black person. In the early 1960s he discovered the caravan wreck site at Ma'adin Ijafen.