PHOTO SOURCE: M. Domínguez-Rodrigo
Spanish researchers in East Africa have found a nearly 2 million year old fossil that they consider to be the oldest “modern” hand bone ever discovered.
The remains, which were found in Tanzania’s Olduvai Gorge, are a phalanx in the left hand pinky finger of a human’s evolutionary ancestor. The ancestor was probably about six feet tall, according to researchers, who have named it “OH 86.”
LARGER THAN CONTEMPORARIES
“Our discovery not only shows that a creature with a modern-looking hand bone
existed 1.85 million years ago, it also shows that OH 86 was bigger sized than any other prior and contemporary hominin,” said the study’s lead scientist, Manual Dominguez-Rodrigo.
The first biped hominids existed 6 million years ago. Like modern monkeys, they often climbed trees during their first four million years of existence, but walked upright as humans do today. The use of both methods of traveling is called “double locomotion”. However OH 86’s hand bone indicates that he traveled differently.
EVOLUTION AND THE ANCESTOR’S HAND BONE
“This bone belongs to somebody who’s not spending any time in the trees at all,” Dominguez Rodrigo in a statement to the New Scientist. He is a scholar at the Africa Evolution Institute in Madrid.
Could our hand bones really be considered primitive?
“Our hand evolved to make possible a vast variety of grips and enough pressing force to allow the broadest range of manipulations” Dominguez Rodrigo said. Stone tools were first used by human ancestors 2.6 million years ago, about seven after OH 86 is thought to have lived.
According to Dominguez Rodrigo, these hand bone changes occurred to increase the bipeds’ ability with manipulating objects. “It is precisely this ability to manipulate which interacted with the brain in the development of our intelligence through the invention and use of tools,” the scientist said.
MORE RESEARCH IS NEEDED
Though the fact that “several key aspects of modern human body morphology emerged very early in human evolution” is indicated by the discovery, the scientists acknowledged that a corresponding skull would be necessary to match with the ancestor’s pinky.
Currently, the team is searching for more of the specimen’s bones to confirm theoretical speculation that the hand bone has inspired, the Press Examiner reported.
All of the team’s findings can be found in the Nature Communications journal.
