If there’s one thing paleoanthropology has revealed time and time again, it’s that many transmissions of ancient human species predated us modern humans today.
While Neanderthals and even Homo erectus have become an invariable part of the history of human origins, one lesser-known ancestor seems to predate all others: Homo habilis.
H. habilis has been called the oldest known member within the Homo genus, though not without controversy and ongoing debate.
According to many scientists, species probably walked upright on Earth more than 2 million years ago – which is to say, almost 2 million years ago Homo sapiens it even appeared on the evolutionary tree.
Homo Habilis Meaning
The species’ Latin name, loosely translated as “dexterous man” or “capable man,” alludes to a key characteristic that sets it apart: dexterous hands.
Fossilized specimens include human-like leg and arm bones, suggesting the ability to manipulate objects with precision. And in fact, simple stone tools have been found near some of the earliest H. habilis remains identified by anthropologists.
The enlarged braincase also distinguishes this species from our more distant, early hominid ancestor Australopithecus — famous for its 3-million-year-old age Lucy specimen in Ethiopia.
Read more: Australopithecines: our ancient ape-like ancestors
Characteristics of homo habilis
H. habilis made its debut in the conversation about human origins in the early 1960s, following a series of remarkable discoveries by anthropologists Louis S. B. Leakey and Mary Leakey, who were married.
With a team of researchers, the Leakeys were excavating the Olduvai Gorge in northern Tanzania in the 1950s when they discovered two unique teeth, followed later by a lower jaw and hand bones.
After combining and evaluating their various specimens, they presented a picture that seemed to mix human features with features also seen in apes. Australopithecus.
Read more: Humans evolved from a common ancestor that appeared 6 million years ago
Reliability for new Homo kinds
Louis SB Leakey, with co-authors Phillip Tobias and John Napier, published first paper of H. habilis in Nature in 1964
This work considers three key elements to meet the definition Homo. They claimed that their specimen had a bipedal gait, an upright posture, and the ability to make simple stone tools.
The team had to change the parameters of the position for Homo brain size, as the skull of their specimen, which was thin and rounded, had a smaller braincase than Homo erectus and other early human species.
Subsequent discoveries have indicated that H. habilis probably had an average braincase capacity of about 640 cubic centimeters (CC), compared to 440 CC in Australopithecus. (The equivalent in H. sapiens average just over 1300 CC.)
Other functions observed in H. habilis specimens, including a relatively large facial skeleton with a flattened lower part and particularly long limbs, make it appear as an intermediate species between Australopithecus and H. erectus — although may not be in direct sequence.
Probable remains of the mysterious species have also already been found in northern Kenya, Ethiopia and South Africa.
Read more: What did humans evolve from?
An unfinished evolutionary puzzle
According to paleontologist Bernard Wood, published in 2014 Nature historya discovery of this kind “should remind us how much we don’t know, not how much we do.”
Leakey’s findings in the 1960s certainly shifted the search for the earliest humans from Asia to Africa. But there may be others Homo ancestors yet to be named and discovered.
In particular, the world the oldest known stone tools they now appear more than 3 million years ago in the fossil record, which seems to be quite a bit earlier H. habilis. And scientists still aren’t sure which species created these tools.
If it was not Australopithecus, perhaps there is another convenient antecedent H. habilis waiting to be revealed.
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