In 1964, a team of palaeontologists led by the eminent Louis Leakey announced the discovery of human fossils from the excavation site at Olduvai Gorge, Tanzania. After identifying the specific anatomy of the fossils, the new species of humans was named as Homo Habilis by the team. The anatomy of Homo habilis was distinct from the human genus of Australopithecus as the members of Homo habilis possessed large bodies with larger brains but smaller teeth. The team identified that the human members of Homo habilis were the original creators of the simple Oldowan tools which were previously excavated from the same sedimentary layers of the gorge. These tools which resembled simple stone knives were made after round rocks called hammerstones were struck against angular rocks called cores after striking off sharp flakes of stone. Homo habilis’ tool-making expertise arouse from their specific behavioural pattern which was also a key factor in distinguishing them from the other species of humans.
In 1981, animal fossils with deep cut marks were recovered from the Olduvai gorge which made the palaeontologists presume that these cut marks were made with the unique tools developed by the Homo habilis who might have wielded their large stone weapons to butcher the animals. Thus, the specific patterns of tool-making and meat-eating were identified to be the novel behaviours that defined the species of Homo habilis.
Features
- Discovery Date: 1960
- Where Lived: Eastern and Southern Africa
- When Lived: 2.4 million to 1.4 million years ago
- Homo habilis face illustration, front view
- Height: average 100 – 135 cm
- Weight: average 32 kg
- Nickname: Handy Man
A Homo habilis brain weighed an average of 610 cubic centimetres which showed a significant increase when compared to an australopithecine brain. In Homo habilis, the hole through which the spinal cord passes was located in the centre of the skull base which proves that the members of the species walked on two legs. However, their legs were relatively short and proportionate to the size of the arms, making them ape-like creatures. Thus, they resembled the australopithecines, their ancestors. They possessed a reduced facial projection when compared to the earlier humans. They also had distinctly shaped finger bones, which were not as curved as the finger bones of quadrupedal apes and not as straight as the finger bones of the modern humans. These peculiar finger bones suggest Homo habilis’ ability for precision grip.
Homo habilis predominantly occupied and dwelled in grassland environments whose climatic conditions fluctuated, changing from cold to dry weather. These climatic conditions might have facilitated the development of new feeding strategies which included scavenging and using of tools. The tools used by Homo habilis were simple progressions of sticks and natural, unmodified stones which were used by the earliest human ancestors. The sharp edged Oldowan tools were created by striking a stone (the hammerstone) against another stone (the core) and removing one or more rock fragments (flakes).
How do we know
A team led by scientists Louis and Mary Leakey uncovered the fossilized remains of a unique early human between 1960 and 1963 at Olduvai Gorge in Tanzania. The type speciman, OH 7, was found by Jonathan Leakey, so was nicknamed “Jonny’s child.” Because this early human had a combination of features different from those seen in Australopithecus, Louis Leakey, South African scientist Philip Tobias, and British scientist John Napier declared these fossils a new species, and called them Homo habilis (meaning ‘handy man’), because they suspected that it was this slightly larger-brained early human that made the thousands of stone tools also found at Olduvai Gorge.
The stone tools and unused waste materials (mainly crude chopping tools and sharp flakes) left by H. habilis provide important clues about the behaviour of these early humans. Olduvai Gorge has been a rich source of Oldowan tools, and the tools are often found with animal fossils. Analysis of the Olduvai animal fossils shows that some cut marks must have been made by stone tools and some and some by carnivore teeth indicating that the animals were killed by nonhominin predators. In all likelihood, the hominins at Olduvai could obtain larger carcasses only after the animals had been killed and partially eaten by other predators. H. habilis may have hunted small prey, such as antelopes, but essentially was a scavenger. Its name, which means ‘handy man,’ was given in 1964 because this species was thought to represent the first maker of stone tools. Currently, the oldest stone tools are dated slightly older than the oldest evidence of the genus Homo.
This species, along with H. rudolfensis, is one of the earliest members of the genus Homo. Many scientists think it is an ancestor of later species of Homo, possibly on our own branch of the family tree. While scientists used to think that H. habilis was the ancestor of Homo erectus, recent discoveries in 2000 of a relatively late 1.44 million-year-old Homo habilis (KNM-ER 42703) and a relatively early 1.55 million-year-old H. erectus (KNM-ER 42700) from the same area of northern Kenya (Ileret, Lake Turkana) challenged the conventional view that these species evolved one after the other. Instead, this evidence – along with other fossils – demonstrate that they co-existed in Eastern Africa for almost half a million years.
The ongoing debate about the origins of our genus is part of H. Habilis’ legacy. All these discoveries should remind us of how much we don’t know, rather than how much we do.
Fossils
- OH 62 – a 1.8-million-year-old partial skeleton discovered in1986 by Tim White in Olduvai Gorge, Tanzania. These remains are thought to be those of a female because of the short stature. This partial skeleton was discovered as 302 fragments of fossilised tooth and bone. It was an important discovery because it enabled this species’ arm, leg and body proportions to be determined. These proportions revealed that this Homo habilis was more ape-like than previously believed. Like apes, this individual had relatively long arms and short legs.
- KNM-ER 1813 – a 1.9-million-year-old skull discovered in1973 by Kamoya Kimeu in Koobi Fora, East Turkana, Kenya. This adult skull has a brain size of only 510 cubic centimetres, which is only just above the average for species placed in the Australopithecus genus.
- ‘Twiggy’ OH 24 – a 1.8-million-year-old skull discovered in 1968 by Peter Nzube in Olduvai Gorge, Tanzania. When found, this skull had been badly crushed and was reconstructed from hundreds of fragments. It also shows some distortion of the bones that occurred before fossilisation was complete.
- ‘Cindy’ OH 13 – a 1.7-million-year-old lower jaw discovered in Olduvai Gorge, Tanzania. This jaw was found with other pieces of the skull and a lower arm bone.
- ‘Jonny’s Child’ OH 7 – a 1.8-million-year-old partial skeleton discovered in 1960 by Jonathan Leakey in Olduvai Gorge, Tanzania. This partial skeleton belongs to a boy and was selected as the ‘type specimen’ or official representative of this species.
- OH 35 – lower leg bones discovered in 1960 in Olduvai Gorge, Tanzania. These leg bones and the OH 8 foot bones may have come from the same individual.
- OH 8 – 1.8-million-year-old foot bones discovered in 1960 in Olduvai Gorge, Tanzania. This partial left foot lacks its heel and toe bones but the foot’s arch and general shape are similar to our own and provide evidence that this species’ walking gait was identical to that of a modern human.
- AL 666-1 – a lower jaw Homo sp. (species unknown) discovered in 1994 in Hadar, Ethiopia. This jaw has the distinctive dental arch of humans. It has therefore been classified in the genus Homo, but its actual species designation is uncertain – it may be Homo habilis or it may even be a totally new species of early human. At 2.3 million years in age, it is the oldest known Homo found directly associated with stone tools.
- KNM-ER 42703 – a right upper jaw bone dated to about 1.44 million years old, discovered in Ileret, Kenya, in 2000. It is the youngest fossil of Homo habilis yet found.