The theory of human evolution postulates that modern homo sapiens’ ancestors were ancient apes. Affirming this theory is the latest research that studied a well-preserved skeleton from four million years ago. Scientists from the Texas A&M University have published their paper in the Science Advances talks about what their findings suggest.
The team of four scientists — Thomas C. Prang, Kristen Ramirez, Mark Grabowski, and Scott A. Williams studied the skeletal remains of Ardipithecus ramidus, also known as Ardi,which dated back to 4.4 million years old. The ancient skeleton was found in Ethiopia and one of its hands was exceptionally well-preserved which eventually made the basis of the research results.
Comparing the shape of Ardi’s hand to several other hand specimens of recent humans, apes, and monkeys which was measured from bones in museum collections around the world, the researchers made comparisons of the kind of locomotor actions used by the earliest hominids or fossil human relatives.Speaking to Texas A&M Today, assistant professor of anthropology and lead author of the paper, Thomas Prang said that the bone shape gives clues into certain kinds of adaptation to habits or lifestyles. By drawing connections between bone shape and behavior among living forms, the scientists could make inferences about the behavior of extinct species, such as Ardi, that cannot be observed directly.
Thomas further said that their study additionally found evidence for a big evolutionary leap between the kind of hand represented by Ardi and all later hominin hands, including that of a famous 3.2 million-year-old well-preserved skeleton found in the same area in the 1970s.
Thomas said that this ‘evolutionary jump’ occurred at a crucial time when hominins were adapting to a more human-like form of upright walking, and the earliest evidence for hominin stone-tool making and stone-tool use, such as cut-marks on animal fossils, were also discovered from this time. The study is in agreement with the classic idea first proposed by Charles Darwin in 1871 that the use of the hands and upper limbs for manipulation appeared in early human relatives in connection with upright walking, says Thomas.
Scientists believe that the evolution of human hands and feet most likely happened in a correlated fashion. Studying the ancient skeleton, researchers believe that it might retain skeletal features that were present in the last common ancestor of humans and chimpanzees and if that is the case, then it could provide researchers a great insight into placing the origin of the human lineage, in addition to upright walking, into a better light.
The results of this study published on Tuesday provides clues about how early humans began to walk upright and make similar movements that all humans perform today.