Tuesday, September 1, 2015

Human Body now 4G

Human Body Has Undergone Four Stages Of Evolution, Finds New Study (Focus News Bureau)02.09.2015

The human body has undergone four stages of evolution, according to recent study conducted by a team of international scientists who studied fossils from the Sima de los Huesos in Spain’s Sierra de Atapuerca.
Dated to around 430,000 years ago, this cave site preserves a large collection of fossils attributed to an enigmatic hominin species, named the Sima de los Huesos
hominin after the site.

Prof Arsuaga and co-authors found that the Sima de los Huesos individuals were relatively tall, with wide, muscular bodies and less brain mass relative to body mass compared to Neanderthals. They shared many anatomical features with the later Neanderthals not present in anatomically modern Homo sapiens, and analysis of their postcranial skeletons (the bones of the body other than the skull) indicated that they are closely related evolutionarily to Neanderthals.



“This is really interesting since it suggests that the evolutionary process in our genus is largely characterized by stasis (i.e. little to no evolutionary change) in body form for most of our evolutionary history,” Rolf Quam of Binghamton University said in a press release.

Comparison of the Sima de los Huesos fossils with the rest of the human fossil record suggests that the evolution of the human body has gone through four main stages, depending on the degree of arboreality (living in the trees) and bipedalism (walking on two legs).

The Sima de los Huesos fossils represent the third stage, with tall, wide and robust bodies and an exclusively terrestrial bipedalism, with no evidence of arboreal behaviors.

This same body form was likely shared with earlier members of our genus, such as Homo erectus, as well as some later members, including the Neanderthals.

Thus, this body form seems to have been present in the genus Homo for over a million years.

It was not until the appearance of our own species, Homo sapiens, when a new taller, lighter and narrower body form emerged.

They describe their findings in a paper in the Proceedings of the National Academy of Sciences.

No comments:

Post a Comment