IT WAS out in the desert of New Mexico that humanity first tested the atomic bomb, creating an explosion that left an indelible imprint on our planet. In the same area, just a few dozen kilometres south, scientists are now finding imprints of quite a different sort: human footprints from the Stone Age. These tracks don’t have anything like the historical significance of the first nuclear test – and that is precisely why they are so important.
Archaeology often focuses on the big picture: technological shifts, epic migrations, the fall of civilisations. By contrast, the stones and bones we dig up …