It has only been recently that anthropologists have realised that their best friends are volcanoes. The ash falling from a series of eruptions can produce sequences of fossils nearly as good as those that are normally formed by silt in the sea, and their dates can be accurately measured. Skeletons preserved in this way in the Great Rift Valley of Africa have revolutionised knowledge of man's ancestry. The first were found by the Leakey family at Olduvai in Tanzania. Expeditions were then undertaken by teams from various countries to sites further north, around Lake Turkana in Kenya, in the Omo Valley, and at Hadar in the Afar triangle in Ethiopia.

LRB 21 May 1981 | PDF Download