A team of anthropologists discovered that australopiths, one of the earliest human species that lived more than 3 million years ago, had the capacity to use stone tools by grabbing them with their hands.
Tracy Kivell and Matthew Skinner from the University of Kent analyzed the internal structure of a type of bone called the trabeculae.
According to the scientists, the trabecular bone has the ability to remodel very fast throughout a life time and it reflects the type of behavior an individual had.
The two researchers first analyzed the trabeculae hand bones that belong to chimpanzees and humans. Their analysis revealed that there are obvious differences between the hand structure humans compared to the ones of chimpanzees have.
According to the scientists, chimpanzees do not have the capacity of adopting human-like postures with their hands. Humans, unlike chimpanzees, can grip using their thumb and other fingers.
This unique ability of grasping things using the thumb and the fingers was found in the early human species like the Neanderthals and other human species that lived on the ground and could use their hands to make stone tools.
The scientists found that one of the earliest known species of humans, the Australopithecus africanus, who lived in the South African regions, had similar trabecular bone structure with the modern human. The study revealed that the Australopithecus africanus could use the thumb and the palm to grab and use tools.
The authors wrote in their study that the new findings support previous archaeological studies that found evidence of stone tool use in early human ancestors like the australopiths. They added that the new results provide evidence that these early humans used their hands in more human-like postures than it was previously believed.
This ability was not found in species like the chimpanzee, which is the closest genetic relative of the modern human.
Kivell and Skinner worked in collaboration with a team of researchers from the University College London, Vienna University of Technology and Max Planck Institute for Evolutionary Anthropology from Leipzig.
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