Homo heidelbergensis

The story

A jawbone in a sand pit

On 21 October 1907, in a sand pit near the village of Mauer, a few kilometres from Heidelberg in Germany, a worker named Daniel Hartmann lifted a strange object with his shovel. It was a big, heavy jawbone, with the teeth still in place. Hartmann handed it to Otto Schoetensack, a professor at the University of Heidelberg who for years had been asking the quarrymen to let him know if they found ancient bones. Schoetensack studied it and in 1908 described it with a completely new name: Homo heidelbergensis, that is, “Heidelberg man”.

The Mauer jawbone is very robust and has no chin, but its teeth are small and similar in shape to ours. For Schoetensack they were proof of a human form older than the Neanderthals. Today it is dated by modern methods to about 600,000 years ago. For decades it remained the main fossil of the species; then many others turned up.

A hunter of big animals

Homo heidelbergensis lived in Africa and Europe, perhaps also in Asia, between about 700,000 and 200,000 years ago. The men were tall and sturdy: a shin bone found at Boxgrove in the south of England, about half a million years old, belonged to an individual perhaps 1.8 metres tall and very heavy. The brain was large, between 1,100 and 1,400 cubic centimetres, close to ours. The forehead, however, was low and the brow ridges above the eyes jutted out a lot.

They got their food by hunting, and they did it well. At Boxgrove archaeologists have found bones of rhinoceroses and horses with cut marks, left by flint blades made on the spot. Even more surprising is the site of Schöningen in Germany: there, on the shore of an ancient lake, about ten spears of pine and spruce wood, up to more than two metres long, were found in 1994 and in the following years, together with the bones of dozens of horses. They are between 300,000 and 200,000 years old (the most recent datings favour 200,000, when Neanderthals already lived in Europe). They are the oldest wooden weapons kept whole, and they show that whoever made them knew how to choose trees, shape the wood and balance the weapon like a javelin.

The Sima de los Huesos

In Spain, near Burgos, in the Sierra de Atapuerca, a deep shaft in a cave is called the “Sima de los Huesos”, that is, the “Pit of the Bones”. Since the 1970s and 1980s the remains of at least twenty-eight individuals of about 430,000 years ago have been found there: a treasure for palaeontologists. Some of them were assigned to heidelbergensis; today many scholars consider them rather the earliest relatives of the Neanderthals, because DNA analysis has shown a strong genetic closeness. Why so many bodies ended up at the bottom of that shaft is one of the great mysteries. Some think of a deliberate deposit of the dead, others of natural causes; nothing is certain.

Who were they really?

The hardest question concerns classification. The name heidelbergensis is used for very different fossils, from Africa and Europe, which lived at times far apart. Some scholars consider them a single broad species. Others prefer to divide them: the African fossils, such as the famous skull from Kabwe in Zambia, found in 1921 by a miner and dated to about 300,000 years ago, are sometimes called Homo rhodesiensis, while the European ones would be linked to the Neanderthal line.

Whatever the name, the basic idea holds: around half a million years ago there was a fairly large population in Africa from which two branches split off. One, in Europe and western Asia, led to the Neanderthals; the other, in Africa, to Homo sapiens. Estimates of the split, made from DNA, fall between about 800,000 and 500,000 years ago. Heidelbergensis, or someone very like it, is therefore the grandfather of both.

We also know that these groups could build shelters and use fire, and that they began to make the first objects that were not purely practical: at Boxgrove and other sites there are stones worked with a perfection that goes beyond usefulness, almost for the pleasure of making them well.