Oldoway man: a Middle Pleistocene Homo sapiens?

“Oldoway Man”: two views of the skull discovered by Hans Reck at Olduvai Gorge in 1913

In 1913, Olduvai Gorge lay in Deutsch-Östafrika (German East Africa), now Tanzania. It was only natural that German academics should work in their colonies. In that year, Professor Hans Reck (1886-1937) of the Humboldt-Universität zu Berlin (Humboldt University of Berlin, at the time known as Universität unter den Linden) was shown a skeleton embedded in rock on an east-facing slope of Olduvai Gorge (actually, the Masai name is Oldupai, while Oldoway was the spelling used in Deutsch-Östafrika). The workman who had discovered it had begun to chip away the concreted sediment from around it and Reck decided to lift the entire block containing the bones. This was the first discovery of ancient human remains in the Gorge, which was to become the scene of major discoveries in later years.

Reck was primarily a palaeontologist, accustomed to working with fossils. The fact that the bones were in a highly compacted deposit led him to think that they were of great antiquity. This was backed up by his analysis of the geological sequence in the Gorge. The skeleton was removed from his Bed II, which he dated to more than 150,000 years ago. The deposit is a buff sediment, becoming redder above a discontinuity; this upper level, where the skeleton was found, is fluvio-lacustrine in origin. In other words, it was laid down in river and lake beds.

The skeletal remains included a complete but distorted skull, containing 36 teeth rather than the usual 32. Reck took this to be a ‘primitve’ and therefore early feature of the skeleton. The deposit was so hard that the bones had to be removed with hammers and chisels. Fossils of an extinct elephant, Elephas antiquus recki, were found in the sediments below the level of the skeleton. This led Reck to conclude that the deposit was dated to the Middle Pleistocene. Realising that the discovery of Homo sapiens remains in a deposit of this date would be controversial, he set out to establish whether or not the skeleton belonged to a later burial. He was unable to distinguish evidence for a hole dug into the layer that might have been a grave cut.

It was partly thanks to the controversy surrounding this discovery that the young Louis Leakey (1903-1972) became fascinated with the Olduvai Gorge site. Reck’s skeleton soon became notorious because its age could not be established satisfactorily. As Reck could not return to the site (the United Kingdom acquired Germany’s African colonies after the 1919 Treaty of Versailles), Leakey began his lifetime’s work there. By 1932, the idea that a Middle Pleistocene Homo sapiens had been found at Olduvai had unravelled completely. Why?

Oldway Man reassessed

The geological stratigraphy of Olduvai Gorge, showing the location of Reck’s discovery

Bed II is considerably older than Reck had estimated, but is a deposit that contains numerous Lower Palaeolithic remains. These include Oldowan tools, the earliest technology developed by hominins. They also include the remains of the hominins themselves. Not one discovered since 1913 is of Homo sapiens, though. Instead, this is the bed in which early discoveries of fossils belonging to Homo habilis (known as OH 13 and OH 16, but nicknamed Cindy and George) were made.

Reck had believed that the deposits above the skeleton were undisturbed. However, the skeleton was in a contracted position and virtually complete. This is very different from the usual condition of hominin fossils, which tend to be of body parts rather than complete skeletons. This is made all the more complicated by the fact that the Bed II deposits are water-lain, as Reck had established. A body falling into water will either be dispersed by the movement of water or by scavenging animals, unless it is covered rapidly in silts. It is very unlikely that a corpse falling (or even being laid) in water would remain in a contracted position before being covered in silt, no matter how rapidly it had formed.

The difficulty with accepting Reck’s skeleton as being as old as he claimed is that his work was done without any appreciation of archaeological stratigraphy. Although the deposit was of Middle Pleistocene date, geological analysis of the material surrounding the skeleton showed it to contain red pebbles and limestone chips. These are not found in Bed II, but occur higher up in the sequence, which shows that they are later than it. This makes it certain that the skeleton was intrusive. In other words, it lay in a grave cut down from a higher layer. Reck himself came to accept this explanation.

The ancient date was dismissed by Percy Boswell (1886-1960) in a letter to Nature (13 August 1932: “The Oldoway Human Skeleton”, volume 130, pp 237-8). The notoriously stubborn Louis Leakey agreed with Boswell’s critique. Had there been anatomically modern humans at this date in the Gorge, we would expect to find other remains in Bed II. As we do not, we must question Reck’s original judgement. Most estimates now put the burial at around 20,000 years old.

The ever-useful TalkOrigins website contains a useful (and fully annotated) rebuttal of the claims.