In February, before his main talk on the subject of his book “The Origin of Our Species”, Prof. Chris Stringer of the Natural History Museum spoke briefly about the ancient footprints found in May 2013 at Happisburgh on the Norfolk coast, information on which had been published a few days earlier.  The archaeological team there had noticed a series of depressions in clays eroding out on the beach, a site which within living memory had still been covered by the adjacent but fast receding cliffs, which began to form some 450,000 years ago.  On probably a very hot day, about five individuals walked across the mud of an estuarine area, possibly of the Thames in a more northerly course, which then baked hard, preserving their footprints.  A survey of the prints revealed that the older individuals would have taken about size 7 to 8 shoes and would have been about 5 feet 7 inches tall.   Some were half that size, probably children, so this was perhaps a family group foraging for food such as shellfish.  Within two weeks the prints disappeared; subsequently more appeared but during the next storm the cliff fell on top of them.  But now the team are more geared up for a quick response to footprints.  Who were these ancient people?  Possibly Homo erectus, or Homo antecessor.  Prof. Stringer also showed some scenes from the exhibition at the Natural History Museum: “Britain: One Million Years of the Human Story“ with which he has been closely involved and which had opened only the day before he came to speak to RAS.

Prof. Stringer then came to the main subject of his talk.  10 million years ago, this was a planet of the apes – they were everywhere, in Africa, Europe and Asia, with a huge diversity.  Today, apart from the orang-utan and gibbon in the Far East, they are found only in Africa.  From 7 million years ago, the human line began to diverge.  From 3 million years ago, there is a good fossil record - at 2-4 million years there was Australopithecus, at first ape-like in shape, like the famous 1½ million-year-old skeleton known as Lucy, small with short legs and long arms, but walking upright.  Then there evolved a more modern human body shape: taller, with long legs, shorter arms, a more human-shaped rib cage, and a larger brain.  Stone tools appear from 2½ million years ago, identifiable when they are found alongside animal bones bearing cut marks.

Soon after 2½ million years ago, some humans, probably Homo erectus, left Africa for the first time and spread rapidly, reaching the Far East within a few hundred thousand years.  Human fossils including several skulls found at Dmanisi in Georgia date from 1.8 million years ago.  These are quite primitive, with a small brain, and accompanied by primitive stone tools.  There are also early human fossils in Southern Europe, and humans may have reached Britain by 1 million years ago.

500,000 years ago Homo heidelbergensis is at Boxgrove in Sussex.  Heidelbergensis is thought to have evolved in Africa into modern humans, in Asia into Neanderthals, spreading in 100,000 years as far as Siberia.  Once considered a “missing link”, Neanderthals were actually highly evolved but a distinct species.  They were evolving their own characteristics such as a distinct skull shape, light skin, possibly blue eyes and red hair, derived from a different gene mutation from that which occurs in modern humans.

How did modern humans evolve?  There are several hypotheses: (1) Multi-regionalism:  when Homo erectus originally spread out of Africa, this was the beginning of modern human evolution.  Erectus evolved in the different regions into the different modern human populations, and into Neanderthals, over 1½ million years.  (2) The replacement hypothesis:  Homo erectus spread around the world, but only evolved in Africa into modern humans, who in turn left Africa and replaced the populations around the world, which died out.  (3) The assimilation theory: Erectus absorbed the new humans from Africa and the various populations merged and evolved.

Some 200-160,000 year old fossils from Africa seem to be transitions between Homo heidelbergensis and Homo sapiens.  Modern human behaviour turns up in Africa - at 150,000 years the gluing of blades to handles with resin, the use of colour pigments, perhaps for body adornment.  From Morocco to South Africa to the Middle East the same objects are found:  shell beads, pigment blocks.  The Sahara Desert was not the barrier it is now: it was fertile with rivers emptying into the Mediterranean.  In 1974, working towards his Ph.D., Chris visited museums around Europe measuring fossil skulls there.   All 400 skulls fell within the range of variation of modern human skulls, even 100,000-year-old skulls from Africa.  Homo erectus skulls are quite different.

Modern humans are all inter-fertile, despite regional variation, which probably evolved over different time scales and due to different processes.  Moderns developed complex behaviour and complex tools.  They started making objects such as the Venus figurines, some of which are made of clay mixed with bone powder and then fired at a high temperature.  Found over a very wide area, the figurines suggest a common belief system which spread across Europe and Asia some 30,000 years ago.  There is also cave art from 35,000 years ago, such as in Chauvet Cave in France, and they must also have had music as they made flutes from bone and ivory, which suggests spirituality.  Burials in central Asia contain mammoth ivory objects which must have taken many hours to fashion, such as the javelin made from a curved tusk which has been straightened, perhaps necessitating the use of clamps and a long steaming process.  All this probably means that the afterlife was already important.

Yvonne Masson