Homo erectus

Homo erectus
Homme de Tautavel 01-08.jpg
Reconstructed skeleton of
Tautavel Man[2]
Scientific classification edit
Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Primates
Suborder:Haplorhini
Infraorder:Simiiformes
Family:Hominidae
Subfamily:Homininae
Tribe:Hominini
Genus:Homo
Species:
H. erectus
Binomial name
Homo erectus
(Dubois, 1893)
Synonyms
Forensic reconstruction of an adult female Homo erectus.[3]
Forensic reconstruction of an adult male Homo erectus.[4]

Homo erectus (meaning 'upright man') is a species of archaic humans that lived throughout most of the Pleistocene geological epoch.Its earliest fossil evidence dates to 1.8 million years ago (discovered 1991 in Dmanisi, Georgia),[5] or possibly even older at 2.1 million years ago (discovered 2018 in the Loess Plateau, China).[6]

H. erectus has been hypothesized as a direct ancestor of the later hominins including Homo heidelbergensis, Homo antecessor, Homo neanderthalensis, Homo denisova, and Homo sapiens.[7]

A debate regarding the classification, ancestry, and progeny of H. erectus, especially in relation to Homo ergaster, is ongoing, with two major positions:

1) H. erectus is the same species as African H. ergaster; or,
2) it is in fact an Asian species or subspecies distinct from African H. ergaster that would later undergo back-migration to Africa, where it would evolve eventually into modern homo sapiens.[8][9]

Some paleoanthropologists consider H. ergaster to be a variety, that is, the "African" variety, of H. erectus; the labels "Homo erectus sensu stricto" (strict sense) for the Asian species and "Homo erectus sensu lato" (broad sense) have been offered for the greater species comprising both Asian and African populations.[10][11]

H. erectus eventually became extinct throughout its range in Africa, Europe and Asia, but developed into derived species, notably Homo heidelbergensis.As a chronospecies, the time of its disappearance is thus a matter of contention. The species name proposed in 1950defines Java Man as the type specimen (now H. e. erectus). Since then, there has been a trend in palaeoanthropology of reducing the number of proposed species of Homo, to the point where H. erectus includes allearly (Lower Paleolithic) forms of Homo sufficiently derived from H. habilis anddistinct from early H. heidelbergensis (in Africa also known as H. rhodesiensis).[12] In this wider sense, H. erectus had mostly been replaced by H. heidelbergensis by about 300,000 years ago, with possible late survival in Java as late as 70,000 years ago.[1]The discovery of the morphologically divergent Dmanisi skull 5 in 2013 has reinforced the trend of subsuming fossils formerly given separate species names under H. erectus considered as a wide-ranging, polymorphous species.[13] Thus, H. ergaster is now well within the accepted morphological range of H. erectus, and it has been suggested that even H. rudolfensis and H. habilis (alternatively suggested as late forms of Australopithecus rather than early Homo)should be considered early varieties of H. erectus.[14][15]

Discovery and type specimen

The Dutch anatomist Eugène Dubois, inspired by Darwin's theory of evolution as it applied to humanity, set out in 1886 for Asia (despite Darwin's theory of African origin) to find a human ancestor. In 1891–92, his team discovered first a tooth, then a skullcap, and finally a femur of a human fossil on the island of Java, Dutch East Indies (now Indonesia). Excavated from the bank of the Solo River at Trinil, in East Java, he first (1893) allocated the material to a genus of fossil chimpanzees as Anthropopithecus erectus, then the following year assigned his species to a new genus as Pithecanthropus erectus (the genus name had been coined by Ernst Haeckel in 1868 for the hypothetical link between humans and fossil Apes)—from the Greek πίθηκος (píthēkos, "ape") and ἄνθρωπος (ánthrōpos, "human")—based on the proposal that the femur suggested that the creature had been bipedal, like Homo sapiens.

Dubois' 1891 find was the first fossil of a Homo-species (or any hominin species) found as result of a directed expedition and search (the first recognized human fossil had been the circumstantial discovery of Homo neanderthalensis in 1856; see List of human evolution fossils). The Java fossil from Indonesia aroused much public interest. It was dubbed by the popular press as Java Man; but few scientists accepted Dubois' argument that his fossil was the transitional form—the so-called "missing link"—between humans and nonhuman apes.[16]

Poster of Homo georgicus. National Archaeological Museum of Spain.

Most of the spectacular discoveries of H. erectus next took place at the Zhoukoudian Project, now known as the Peking Man site, in Zhoukoudian, China. This site was first discovered by Johan Gunnar Andersson in 1921[17] and was first excavated in 1921, and produced two human teeth.[18] Davidson Black's initial description (1921) of a lower molar as belonging to a previously unknown species (which he named Sinanthropus pekinensis)[19] prompted widely publicized interest. Extensive excavations followed, which altogether uncovered 200 human fossils from more than 40 individuals including five nearly complete skullcaps.[20] Franz Weidenreich provided much of the detailed description of this material in several monographs published in the journal Palaeontologica Sinica (Series D).

Nearly all of the original specimens were lost during World War II during an attempt to smuggle them out of China for safekeeping; however, authentic casts were made by Weidenreich, which exist at the American Museum of Natural History in New York City and at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, and are considered to be reliable evidence.

Similarities between Java Man and Peking Man led Ernst Mayr to rename both Homo erectus in 1950.

Throughout much of the 20th century, anthropologists debated the role of H. erectus in human evolution. Early in the century, due in part to the discoveries at Java and Zhoukoudian, the belief that modern humans first evolved in Asia was widely accepted. A few naturalists—Charles Darwin most prominent among them—theorized that humans' earliest ancestors were African: Darwin pointed out that chimpanzees and gorillas, humans' closest relatives, evolved and exist only in Africa.[21]