How to explain the face change in the course of evolution? A new study
The new study complements our knowledge on the evolution of man.
17 APR 2019 18:14
Persons who we daily see before us, have unique distinguishing features that allow us to identify and get to know each other. Scientists from Arizona state University, together with colleagues from other academic institutions examined the evolutionary path, in which formed a human face in its modern form.
Biological species Homo sapiens (lat. Homo sapiens) belongs to the genus of Humans (Homo) from the family of hominids and comes from the Australopithecines, separated by approximately 2.8 million years ago.
C native People of Australopithecus brings the weak development of the jaws, the absence of large protruding fangs, grasping the brush with a developed thumb, the supporting foot and the structure of the pelvis, adapted to bipedalism. The brain of Australopithecus relatively large (530 cm3), but in structure it is closer to the brain of modern great apes.
The most ancient representative of the genus Homo – Homo habilis, or Homo habilis. Weight of the brain of this hominid was 650 grams with a volume of 700 cm3, which is much more than typical of Australopithecus. The more primitive the occipital lobe of the brain of Homo habilis is reduced in favor of progressive lobes – frontal, parietal and temporal. The skull, unlike the Australopithecines, expanded infraorbital and parieto-occipital areas, and the teeth are smaller.
After all, hunter-gatherers, people became farmers, their lives became less active, to get food easier and it is easier to chew. This has led to a redistribution of the proportions of the face: use of the brain for the invention of new technologies has become more important than chewing function. However, evolution faces is not explained.
“Now we can use face to display 20 different categories of emotions through compression or relaxation of muscles. We know that nutrition, respiratory physiology, climate and other factors have played an important role in the development of the modern human face, but the interpretation of its evolution only in this framework would be a strong simplification”, Paul O’higgins, Professor of archaeology at new York University.
Comparison of changes that occurred to the skull and, accordingly, a human face over the past 4.5 million years, the researchers insist on the importance of social ties. They propose to consider the character of his contemporaries as the result of a combination of all aspects: not only biomechanical, but also psychological and social.
To illustrate, the huge brow ridges and large jaws from the extinct members of Homo that have survived from modern apes. In their world this is an opportunity to show their dominance and a symbol of aggression. In contrast, a later people, appreciating all the advantages offered by the cooperation, has learned to restrain his aggression. Instead, he focused on the ability to serve peaceful non-verbal signals, and the corresponding facial structure has become an important tool to achieve this task.
View, how has the face of a man in the process of evolution.