Scientists discover a two-million-year-old vertebra of an extinct species of an ancient human relative Australopithecus sediba. Fossils are the “missing link” proving that early humans used their upper limbs to climb like apes and their lower limbs to walk like humans.

NS Australopithecus sediba It was first described in 2010. At the time, they were in possession of fossil materials from two people that were found in the Malaba Caves in South Africa.

Since the fossils belonging to Karabo and Isa – a male child and an adult female – were found in a cave discovered by miners who blew it up with dynamite, scientists found only part of the bones.

Now type new world, a team of investigators found Four vertebrae fossil from the lower back Issa in addition to the sacral bone that connects the spine to the pelvis.

together form One of the most complete lumbar vertebrae And preserved from the ancient human ancestors already found.

“S” shaped column

After fitting the vertebrae together, experts concluded that the spine formed “S”A characteristic of humans.

This happens because of bipedal behavior. Walking on two legs causes the mass of the body to center over the pelvis, causing the spine to curve.

These details make scientists believe that Australopithecus sediba He was bipedal, or at least he was standing on his two legs most of the time. The conclusions are described in A Scientific material Posted in eLife.

Previous studies had already found obvious upper-body adaptations for tree climbing, which suggests that a. Sediba It was an intermediate species that walked like a human but climbed like a monkey.