The original Trinil 1 (tooth), Trinil 2 (skullcap), and Trinil 3 (femur) specimens discovered by Eugene Dubois on the banks of the Bengawan Solo River in 1891-2, collectively refered to as 'Java Man'. Now in the collection of the Naturalis Biodiversity Center in Leidan, the Netherlands.. Peter Maas/Wikimedia Commons. In 1879, Charles Darwin's book 'The Descent of Man, and Selection in Relation to Sex' had proposed (amongst other things) that modern Humans were descended from African Apes. This was a matter of considerable controversy at the time, with many people, and in particular several religious groups, declaring the proposition highly offensive. Among the scientific community, and in particular those members of it who studied Human and animal anatomy, this was less of a surprise, and broadly in line with what many other people had been thinking.
One aspect of the theory, which was widely contested, however, was the idea that Humanity had originated in Africa. In the nineteenth century, it was generally assumed that civilization had originated in Asia, and spread into Africa via Egypt, which contained the oldest known archaeological sites on the continent at that time. Since Asia is also home to Apes (including the Orangutan, which was then little understood, and many people believed could talk), it seemed quite possible that this continent could have been home to not just the origin of civilization, but the origin of Humanity itself.
Marie Eugène François Thomas Dubois, a trained physician with an interest in zoology working at the University of Amsterdam was inspired by this idea, and sought funding for an expedition to the Dutch East Indies (now Indonesia) to search for evidence of this origin. When this was (unsurprisingly) rejected, he enlisted as a surgeon with the Royal Netherlands East Indies Army, receiving a posting in Sumatra in 1887, where he began is search for a hypothetical Human ancestor.
Dubois's excavations in caves in Sumatra (inspired by the discovery of Neanderthal remains in caves at several locations in Europe), failed to produce any evidence of ancient Humans, but did uncover a range of large Mammal skeletons, bringing him to the attention of the colonial government. Palaeontology was still a new science in the late nineteenth century, and the discovery of large vertebrate fossils was a matter of national prestige. In Europe, an countries such as Britian, France, Germany, and even Belgium had all made impressive discoveries on their home territories, as had the young United States, and British and German colonies in Africa. Neither the Netherlands, nor any of its colonies, had produced any significant fossil discoveries at this time, making Dubois' discoveries significant for the colonial administration.
Marie Eugène François Thomas Dubois (Eugène Dubois). Wikimedia Commons.
In 1889 Dubois was relieved of his military duties, and provided with two assistants from the East Indies Army's corps of engineers, and fifty convict labourers. After another season in Sumatra, during which no Human remains were found, Dubois switched his attention to Java in 1890. This proved to be successful, with his team uncovering the molar and skullcap now known as Java Man in 1891, and the femur in 1892.
Dubois described the molar and skullcap under the name Anthropopithecus, a now obsolete term used to describe both some Hominin fossils (including a tooth from the Sivalik Hills of India, which resembled the one from Java), as well as the living Chimpanzee. He envisaged the living individual as being a Human-like Gibbon (his preferred choice for a Human ancestor) and living Humans. Following the discovery of the femur, which was longer and straighter than that of any Ape, emphasising the Human-like qualities of the remains, Dubois amended this to Anthropopithecus erectus, emphasising that the creature had an upright, Human-like stance.
Dubois was originally cautious about his find, referring to it as a Human-like Ape, but refraining from designating it as a Human ancestor. However, examination of the skull-cap suggested that it had a cranial capacity of about 900 cm², far larger than any Ape, further emphasising the fossil's Human affinities, which led Dubois to redescribe the specimen as Pithecanthropus erectus, using a genus name the German naturalist had used for a (then hypothetical) missing link between Apes and Humans.
In the 1930s German palaeontologist Gustav Heinrich Ralph von Koenigswald carried out a series of further excavations, on Java, uncovering a number of additional Hominin specimens, which he believed to be closely related to those Dubois had discovered, and assigned them to the same species. Surprisingly, Dubois objected strongly to this, claiming that his fossils were those of Ape-men (and therefore a missing link between the two groups) while von Koenigswald's were close to modern Humans.
Following the Second World War various scientists reviewed Dubois' and von Koenigswald's material, as well as other Hominin fossils from other sites in Asia and Africa, coming to the conclusion that these all belonged to a single species, which German biologist Ernst Mayr named Homo erectus, placing it in the same genus as modern Humans, but using Dubois' specific name, which had priority as the first specimen described, thus making Java Man the holotype of the species.
Today it is more-or-less universally accepted that Humanity has its roots in Africa, and Homo erectus is considered to have been the first Human species to have spread out of Africa, moving across Arabia and into South Asia, then China and Southeast Asia, eventually down into the Sundaland Region, which included Sumatra and Java, but which was still attached to mainland Asia during the Pleistocene, when sealevels were generally lower.
Sundaland at the Last Glacial Maximum, showing the modern distribution of land in dark grey and the additional land exposed during the glacial maximum in light grey. The northern boundary of Sundaland defined by 9°N latitude shown as a dashed line. Possible lakes are marked by the letter L, the mouths of the major Molengraaff Rivers are indicated by letters as follows: 1, South Sunda River; 2, North Sunda River; 3, Siam River; 4, Malacca River. Bird et al. (2005). The exact age range of Homo eructus is unclear; fossils dating from between about 1.4 million years ago and about 400 000 years ago have been assigned to the species, although there is considerable variation between these, leading some palaeoanthropologists to split the species into several different species or subspecies. As the holotype of Homo erectus, Java Man always remains within that species, sometimes being assigned to the subspecies Homo erectus erectus, while other specimens are re-assigned based upon their perceived similarity to it. This situation is not helped by the exact age of Java Man being unknown, not simply because dating methods were less advanced in the nineteenth century, but also because Dubois, having been provided with a free workforce by the authorities on Java, was not present when the fossils were excavated by his labourers, and was therefore uncertain about the horizon they were excavated from.
However Homo erectus should be defined, the species is considered to have made remarkable advances over its predecessors, spreading out of Africa and across Asia into a range of entirely new environments, as well as developing the distinctive Acheulean tool set, distinguished by carefully shaped axes and points, unlike anything which had come before it. Homo erectus is also generally credited with having been the first Hominin to use fire, as well as having built the oldest wooden structures in Africa, half a million years ago.
Acheulean hand-axe from a hill-top plateau, 425 m above sealevel, 15 km to the northwest of the city of Naqada, Egypt. In the collection of the Petrie Museum in London. Osama Shukir Muhammed Amin/Wikimedia Commons.
