Homo Naledi; A Human Capable of Living in Trees

A species of early humans had limbs suitable for living both on the ground and in trees. Although researchers still do not know how this extinct species, likely the oldest early human ever discovered, walked, they are certain it was completely different from modern human walking. Modern humans are the only remaining species of humans on Earth, but in ancient times, other human species also lived on this planet. The hominins, scientifically known as Hominini, are a lineage of the subfamily Homininae. This lineage includes all existing or extinct species that are closer to modern humans than to today's chimpanzees. According to Discovery, the latest discovered species of human, named Homo Naledi, had a brain the size of an orange and was advanced enough to perform burial rituals. More than 1,550 bones and bone fragments of this type of human were discovered in a cave in South Africa, which is considered the largest discovery of this type of human on the African continent. However, due to the specific nature of this cave, determining the age of this fossil is still not possible for scientists. Researchers believe that studying the hands and feet of these discovered fossils may help them find reasons for the change in human lifestyle and the shift from walking on all fours to bipedalism. One of the anthropologists' theories is that humans have superiority over other creatures on Earth because they can use their hands to utilize various tools. William Harcourt-Smith, a paleoanthropologist at the American Museum of Natural History, tells Live Science that the feet of this fossil are not exactly like human feet but are more similar to human feet than to other creatures. The study of over 150 hand bones of this fossil shows that this human species had long thumb bones, which later became an important tool for distinguishing humans from chimpanzees in the evolutionary cycle. However, the rounded feet of this fossil are very different from modern human feet. The rounded feet were suited for climbing and living in trees rather than living on the ground. Although, according to Harcourt-Smith, the climbing ability and life in trees of chimpanzees are still much greater than this human species. Jeremy DeSilva, an anthropologist at the University of Durham and another researcher of this study, states that the composition of this fossil shows that the thigh muscles have moved away from the thigh bones, giving this species more strength in walking (on two legs). Over time, the composition of the pelvic bones has also changed, which means more space for the growth of the human fetus's brain.