Homo erectus

The species in brief

Homo erectus (“upright man”) is the human species with the longest known career. Its fossils span from about 1.9 million to about 110,000 years ago, more than 1.7 million years, which is roughly six times as long as our own species has existed. It lived across a huge range: East and South Africa, the Caucasus, India, China and Indonesia.

It was also a turning point in the human story. Earlier relatives such as Homo habilis and the australopiths were still small, with arms built partly for climbing. Homo erectus was tall, long-legged and built for walking and running over long distances, with a bigger brain and a body that looks much more like ours from the neck down.

The body

The best picture of the body comes from Turkana Boy, a nearly complete skeleton found in 1984. It shows:

• Height. Turkana Boy was about 1.6 m (5 ft 3 in) tall when he died, and he was not yet fully grown. Adults of the species ranged from roughly 1.5 to 1.8 m.
• Proportions. Long legs, a narrow pelvis and shorter arms than earlier species. This is a body for striding, and probably for staying cool in the heat, with less need to climb.
• Brain. About 880 cubic centimetres for Turkana Boy. Across the species the range runs from roughly 550 to well over 1,000 cubic centimetres, growing over time.
• Skull. Thick bones, a heavy brow ridge, a low sloping forehead, a long low braincase and no chin. The face is flatter and the teeth smaller than in the australopiths.

How fast children grew is still debated. Studies of Turkana Boy’s teeth suggest he may have been younger than his tall frame suggests, perhaps around eight, with a growth pace between that of apes and modern humans.

Out of Africa, the first time

The oldest fossils that most researchers place in the species come from Africa. A skull from Drimolen in South Africa, catalogued DNH 134, was dated in 2020 to about 2.04 to 1.95 million years ago. In East Africa, the Koobi Fora and West Turkana fossils from about 1.9 to 1.5 million years ago are the classic early examples. Some of these African fossils are given their own name, Homo ergaster, by researchers who think the Asian and African fossils belong to different species. That argument is not settled, and this site uses Homo erectus in the broad sense.

Soon after, the species turned up far away. At Dmanisi in Georgia, about 1.8 million years ago, a site on a hilltop beside old river valleys has produced skulls, jaws and bones from several individuals. Some of the Dmanisi skulls are small, with brains of about 550 to 650 cubic centimetres, and they differ quite a lot from one another. That variety is a large part of why some researchers think the many named early Homo species may really be variations within one.

Dmanisi also holds an older individual who had lost nearly all his teeth well before death. He could only have survived for some time with help in chewing and finding food, which hints that these people looked after each other.

By roughly 1.5 million years ago or soon after, Homo erectus was in Java, and it reached China probably more than a million years ago. Sangiran in Java and Lantian in China are among the best known early Asian sites, though the dates of some of the oldest Asian fossils are still argued over.

Famous finds

• Java Man (Trinil, Indonesia). Eugène Dubois joined the Dutch army as a doctor in order to go to Indonesia and look for the “missing link”. He found a skullcap in 1891 and a thigh bone in 1892. The thigh bone looked so modern that he named the species for walking upright. His fossils are kept at the Naturalis museum in Leiden.
• Peking Man (Zhoukoudian, China). Excavations began in the 1920s and a first skullcap was found in 1929 by Pei Wenzhong. Over the next decade the site gave up fossils from dozens of individuals. Most of the original bones disappeared in 1941, while being moved to safety during the war, and have never been found. Casts and the careful studies by Franz Weidenreich survive. See the Zhoukoudian page.
• Turkana Boy (Nariokotome, Kenya). Found in 1984 by Kamoya Kimeu, a member of Richard Leakey’s team, in the sandy bed of a seasonal river. About 1.5 million years old, he is the most complete early human skeleton known.
• Ngandong (Java). A group of skulls and leg bones from a river terrace. Dating published in 2019 put them at about 117,000 to 108,000 years ago, making them the youngest known Homo erectus anywhere.
• Ileret footprints (Kenya). Trails of footprints about 1.5 million years old, preserved in mud near Lake Turkana, are among the best evidence of how these people walked. They are very close to modern human prints. The same lake basin, at Koobi Fora, holds many Homo erectus fossils.

Tools and fire

Early Homo erectus used the simple stone flakes and choppers known as Oldowan tools. Around 1.76 million years ago, at Kokiselei in West Turkana, the first Acheulean tools appear: large, shaped stone hand axes and cleavers, worked on both sides. These are the first tools that look as if the maker had a design in mind before starting. The Acheulean lasted well over a million years and spread across Africa, western Asia and Europe, though in much of East Asia people made different tools, with few hand axes.

Fire is harder. Clear signs of fire in human sites appear by about a million years ago, and the best early examples are at Wonderwerk Cave in South Africa (about 1 million years ago) and Gesher Benot Ya’aqov in Israel (about 780,000 years ago). Whether Homo erectus could light fires at will, or only used natural ones, and how much it cooked, are still open questions. Some researchers argue cooking helped the brain to grow because cooked food gives more energy for less chewing.

At Trinil, a shell with a zigzag pattern engraved on it, about 430,000 to 540,000 years old, was reported in 2014. If the dating and the engraver are right, it is the oldest known deliberate engraving, made by a Homo erectus hand.

What did it eat, and how did it live?

Homo erectus ate a wide mix: plants, roots and fruits, and a good deal of meat. Cut marks on animal bones at sites like Koobi Fora show it was butchering carcasses with stone tools. Whether it hunted large animals or mostly scavenged them is still argued, and probably it did both. Living in groups, caring for the sick and sharing food all look likely, but are inferred from a few finds, not demonstrated for the species as a whole.

Where it fits in the family tree

Homo erectus probably descends from an early Homo species in Africa, perhaps Homo habilis or something close to it, though the 2020 Drimolen skull shows that erectus and its relatives overlapped with them for a long time in the same region. At Ileret in Kenya, habilis and erectus were living side by side 1.5 million years ago.

Later, the African branch probably led to Homo heidelbergensis and eventually to us and to the Neanderthals. The Asian branch continued to about 110,000 years ago, and may have been a dead end. The small people of Flores, Homo floresiensis, may have descended from early erectus or something similar, but that is also debated.

Where to see it

Turkana Boy belongs to the National Museum of Kenya in Nairobi, where the skeleton is studied and displayed. Casts of Peking Man are shown in China and in many museums abroad, and the Zhoukoudian site has a museum. The Dmanisi site and museum in Georgia are open to visitors. Dubois’s Java fossils are at Naturalis, Leiden.

Sources

• Smithsonian National Museum of Natural History, Human Origins Program. Homo erectus.
• Herries, A. I. R. and others (2020). Contemporaneity of Australopithecus, Paranthropus, and early Homo erectus in South Africa. Science 368: eaaw7293.
• Lordkipanidze, D. and others (2013). A complete skull from Dmanisi, Georgia, and the evolutionary biology of early Homo. Science 342: 326 to 331.
• Walker, A. and Leakey, R. (eds.) (1993). The Nariokotome Homo erectus Skeleton. Harvard University Press.
• Rizal, Y. and others (2020). Last appearance of Homo erectus at Ngandong, Java, 117,000 to 108,000 years ago. Nature 577: 381 to 385.
• Joordens, J. C. A. and others (2015). Homo erectus at Trinil on Java used shells for tool production and engraving. Nature 518: 228 to 231.
• Lepre, C. J. and others (2011). An earlier origin for the Acheulian. Nature 477: 82 to 85.
• Bennett, M. R. and others (2009). Early hominin foot morphology based on 1.5-million-year-old footprints from Ileret, Kenya. Science 323: 1197 to 1201.