It is the first human species to evolve a humanlike body plan and gait, to leave Africa and colonize Asia and Europe, and to wield fire.

East Asian H. erectus normally have more robust skeletons and larger brain volumes — averaging 1,000 cc (61 cu in), within the range of variation for modern humans.

Despite what Charles Darwin had hypothesized in his 1871 Descent of Man,[b] many late-19th century evolutionary naturalists postulated that Asia (instead of Africa) was the birthplace of humankind.

[3] Dutch scientist Eugène Dubois joined the Royal Netherlands East Indies Army to search for the "missing link" in Java.

[7] He unfruitfully attempted to convince the European scientific community that he had found an upright-walking ape-man dating to the late Pliocene or Early Pleistocene; they dismissed his findings as some kind of malformed non-human ape.

[8][9] This characterization became better supported as German-Dutch palaeontologist Gustav Heinrich Ralph von Koenigswald discovered more Indonesian ancient human remains over the decade at Mojokerto, Sangiran, and Ngandong.

[13][14] As the importance of racial distinction diminished with the development of modern evolutionary synthesis, many fossil human species and genera around Asia, Africa, and Europe (including "Pithecanthropus" and "Sinanthropus") were reclassified as subspecies of Homo erectus.

[15][16] In the late 20th century, some of the oldest H. erectus fossils were being discovered across Africa, the first being Kenyan archeologist Louis Leakey's Olduvai Hominin 9 in 1960.

[18] By the middle of the 20th century, human taxonomy was in turmoil, with many poorly-defined species and genera described across Europe, Asia, and Africa, which overexaggerated how different these fossils actually are from each other.

[13] In 1950, German-American evolutionary biologist Ernst Mayr had entered the field of anthropology, and, surveying a "bewildering diversity of names", decided to subsume human fossils into three species of Homo: "H. transvaalensis" (the australopithecines), H. erectus (including "Sinanthropus", "Pithecanthropus", and various other Asian, African, and European taxa), and H. sapiens (including anything younger than H. erectus, such as modern humans and Neanderthals), as had been broadly recommended by various priors.

[f][14] Though later Mayr changed his opinion on the australopithecines (recognizing Australopithecus), his more conservative view of archaic human diversity became widely adopted in the subsequent decades.

[30][31] The oldest identified H. erectus specimen is a 2.04 million year old skull, DNH 143, from Drimolen, South Africa, coexisting with the australopithecine Paranthropus robustus.

[h] Populations spread out via open grassland and woodland savannas, which were expanding due to a global aridification trend at the onset of the Quaternary glaciation.

[42][i] Most H. erectus sensu lato specimens date to 1.8 to 1 million years ago in the Early Pleistocene before giving way to descendant species.

[46] Dubois originally described the species using a skullcap, noting the traits of a low and thickened cranial vault and a continuous bar of bone forming the brow ridge (supraorbital torus).

[50] H. erectus was the first human species with a fleshy nose, which is generally thought to have evolved in response to breathing dry air in order to retain moisture.

[51] Compared to earlier Homo, H. erectus has smaller teeth, thinner enamel, and weaker mandibles (jawbone), likely due to a greater reliance on tool use and food processing.

[n] Genetic analysis suggests that high activity in the melanocortin 1 receptor, which would produce dark skin, dates back to 1.2 million years ago.

[69] The bones are extraordinarily thickened, particularly in Homo erectus sensu stricto, so much so that skull fragments have sometimes been confused for fossil turtle carapaces.

[42] Though scavenging may have instead played a bigger role at least in some populations, H. erectus fossils are often associated with the butchered remains of large herbivores,[76] especially elephants, rhinos, hippos, bovines, and boars.

[77] H. erectus is usually assumed to have practiced sexual division of labor much like recent hunter-gatherer societies, with men hunting and women gathering.

This ideation is supported by a fossil trackway from Ileret, Kenya, made by a probably all-male band of over 20 H. erectus individuals, possibly a hunting party or (similar to chimpanzees) a border patrol group.

[75] H. erectus manufactured Lower Paleolithic technologies, and is credited with the invention of the Acheulean stone tool industry at latest 1.75 million years ago.

Over hundreds of thousands of years, the Achuelean eventually replaced its predecessor — the Oldowan (a chopper and flake industry) — in Africa, and spread out across Western Eurasia.

[87] This sudden innovation was typically explained as a response to environmental instability in order to process more types of food and broaden the diet, which allowed H. erectus to colonize Eurasia.

Some authors have asserted that H. erectus intentionally made these crossings by inventing watercrafts and seafaring so early in time, speaking to advanced cognition and language skills.

This had been reinforced by the historic practice of headhunting and cannibalism in some recent Indonesian, Australian, and Polynesian cultures, which were formerly believed to have directly descended from these H. erectus populations.

An engraved Pseudodon shell DUB1006-fL from Trinil, Java, with geometric markings could possibly be the earliest example of art-making, dating to 546,000 to 436,000 years ago.

A 400,000 year old H. erectus hyoid bone from Castel di Guido, Italy, is bar-shaped—more similar to that of other Homo than to that of non-human apes and Australopithecus—but is devoid of muscle impressions, has a shield-shaped body, and is implied to have had reduced greater horns, meaning H. erectus lacked a humanlike vocal apparatus and thus anatomical prerequisites for a modern human level of speech.

[68] On the other hand, despite the cochlear (ear) anatomy of Sangiran 2 and 4 retaining several traits reminiscent of australopithecines, the hearing range may have included the higher frequencies used to discern speech.