Rumble in the caves over Homo naledi 'burial' theory

Lichen and cave-dwelling snails are at the centre of an academic dispute about whether our earliest relatives mourned and ritually disposed of their dead. The contenders are academics in the same department at Wits University.On one side is Francis Thackeray, director of the Wits Institute of Human Evolution, who suggests that the black spots found on the fossil remains of Homo naledi are a residue left by lichen.