A dazzling new finding and its implications for human evolution were described in an article published in the Nature Communications on Tuesday.
It’s fascinating that such a small fossil can bear such a wealth of information on human evolution. According to lead author of the study, Dr. Manuel Dominguez-Rodrigo, the pinkie fragment or ‘proximal phalanx’ belongs to a hominid that lived approximately 1.84 million years ago.
OH 86 could be part of a human-like hand of a member of the human family that inhabited the earth at roughly the same time as Homo Habilis and Paranthropus Boisei. The first information available from the analysis is that this specific member of the human family was quicker in adapting ‘modern’ features.
According to Dr. Dominguez-Rodrigo, who is also the co-director of the Institute of Evolution, Africa, a ‘modern human-like hand’ indicates the functions that are closer to those developed by modern humans. Specifically, this would evolve around gripping and would lose the functions necessary for escalating, climbing or locomotion. Moreover, these modern functions of the hand are tightly related to tool making and handling.
“For human evolution, the new discovery shows the oldest hominin adapted to terrestrial life completely. This implies a creature using tools more frequently. This modern morphology is also documented in a hominin that is bigger than the other hominins previously known”.
OH 86 is just a fragment of a hand. Nonetheless, it indicated that the hand it belonged to had already developed to modern proportions. Primates’ hands for instance are still adapted for climbing. The curved and elongated bones of the fingers, as well as the short but sturdy bones of their thumbs are the perfect match for grasping tree branches.
The adaptations for modern functions are only observed in Homo sapiens of all other primates. The origin of OH 86 is yet unknown. It might belong Homo Habilis, but yet-again it could be an unknown hominin.
Either way, the fact this finding is key to understanding human evolution cannot be contested. Other fragments have been offering clues of modern adaptations at an earlier time than it was previously assumed due to their morphology.
From a partial mandible, researchers were able to determine the brain capacity that an early hominin could have had. Fragments of pelvic or occipital bones almost contemporary to OH 86 also revealed early modern adaptations.
As such, human evolution and our genus is believed to date start before two million years ago.
Photo Credits: nature.com