Discovery of a fossil bone of a human hand 1.4 million ... - 20minutos.es

Two people work in a reservoir. (Gtres)

Scientists found a hand bone of a human ancestor that wandered the earth in eastern Africa about 1.4 million years makes and they suspect belonged to the early human species, Homo erectus.

This discovery, published in Proceedings of the National Academy of Sciences , is the earliest evidence of a modern human appearance change, indicating that this anatomical feature was over half million years before the known previously.

“This bone is the third metacarpal hand , which is connected with the middle finger. was discovered at the site in West Kaitio Turkana in Kenya,” said Professor of Pathology and Sciences anatomy at the University of Missouri, in the United States, Carol Ward.

“What makes this bone is so different is the presence of a styloid or projection of bone on the end that connects to the wrist. Until now, this process styloid only found in us, Neanderthals and other early hominids, “he adds.

humans have a distinctive anatomy that enables them to make and use tools , a feature that apes and other nonhuman primates do not have and which is unknown at the time that It first appeared in human evolution. The styloid process aid hand bone block wrist bones , allowing a greater amount of applied pressure to the wrist and hand grip for the thumb and fingers.

These early humans were almost certainly using their hands to many other complex tasks Ward and colleagues point out that the lack of styloid process creates challenges for apes and previous human when intetaban making and using tools, so that the lack of a styloid process may have increased the likelihood of having arthritis earlier, according to Ward. The bone was found near the sites where they have appeared early Acheulean stone tools , including hand axes of more than 1.6 million years are included.

Being able to do this kind of accurate tools indicated that these early humans were almost certainly using their hands to many other complex tasks , as the author of the study, carried out by a project team ‘West Turkana Paleo’, led by Fredrick Manthi of the National Museums of Kenya.

“The styloid process reflects greater skill that allowed early human species perform powerful precise grips on the manipulation of objects . This was something that his predecessors could not do for lack of this apophysis styloid and its associated anatomy, “Ward said.