Compared to other hominids, our skeleton is very light . Now, a team of researchers from different international institutions, coordinated by the anthropologist Habiba Chirchir, from the National Museum of Natural History, at the Smithsonian Institution (USA), has discovered that it adopted its current configuration relatively recently, just 12,000 years ago.
To demonstrate this, these scientists studied the joints of chimpanzees, modern Homo sapiens and fossil remains of other extinct species , such as Australopithecus africanus , Paranthropus robustus and Homo neanderthalensis, using high-resolution images. In a study published in the journal Proceedings of the National Academy of Sciences , the authors explain that our ancestors and their relatives maintained high bone density for millions of years, until it experienced a sudden and pronounced decline a few thousand years ago.
This is more drastic in the lower limbs – at the knees, hips and ankles – than in the upper limbs – the hands, elbows and shoulders -, so experts suspect that it could be related to the appearance of agriculture , the abandonment of a nomadic way of life and the adoption of a much more sedentary one.
“In our trial we showed that humans now have less dense bones than other species with which we are related . This is the case in both agricultural and industrial societies, ”says Chirchir. However, the researchers found that the differences with other hominins were minimal as little as 20,000 years ago. Based on this finding, they hope to provide an anthropological context that helps explain the development of some conditions, such as osteoporosis.
Photo: AMNH / J. Steffey
