One of our human ancestors, the Homo Habilis, has offered scientists new insight in the study of brain lateralization as they discovered that the humanoid favored the right hand.
The research, which appeared in Journal of Human Evolution, was led by David Frayer, Kansas University’s professor of anthropology.
Its objective was to study the remains of a Homo Habilis or the OH-65 fossil traces found in Tanzania in the Olduvai Gorge. The area has also revealed quite a number of prehistoric tools. As they were used by the Homo Habilis, their discovery led to the species being nicknamed the “handy-man”.
Scientists believe that the first representatives of the species appeared over 2.1 million years ago, lasted up to 600,000 years, and spent their whole species existence on the African continent.
Whilst studying the OH-65 specimen, scientists observed minute ridges and cuts in its upper front teeth relative area. These marks were most likely produced by the “handy-man”’s use of stone tools when cutting meat or similar products.
Professor Frayer went to explain that the marks were most probably left when the stone tool, used to handle the processed material that was afterward gripped by the teeth, occasionally touched the labial face and thus left a permanent mark on the surface of the teeth.
The direction of the marks and scratches also led to the conclusion that this hominin favored is right-hand. The study’s researchers also believe that the analysis and further studies of future specimens will reveal that most Homo Habilis were or favored the use of their right hand.
The current discovery could help confirm the generally held idea that brain lateralization occurred over 1.8 million years ago, which would be quite early in the evolution of humans and our humanoid ancestors.
The brain lateralization is the brain process of dividing cognitive labor between the brain’s two halves. As the study goes to show, early hominins also seem to have benefited from this brain process.
The possibility of that Homo Habilis may exhibit right-handedness preferences had not been advanced before the discovery and came as quite a surprise.
As in nine cases out of ten, the modern man favors right-handedness, the current research may move along both the humans’ evolution process and that of brain lateralization.
The latter process has been associated with a handedness preference, the brain’s parceling of different activities, and language development.
As just one specimen is inconclusive in terms of a generally accepted theory, scientists are going to continue their searchers for more fossils and their analysis of the Homo Habilis.
Image Source: Wikimedia