Genetic and biological factors of human evolution. Dissemination 86th
The evolution of the human species is marked by a series of genetic factors many of which were devolved before the human species appearance, by geological phenomena such as the Cenozoic glaciation, and genetic factors of our on species and geological peers of our species.
Among the previous genetic factors with the appearance of hominids we highlight genes:
1. MCPH1 related with synthesis of Microcephaly, DNA repair protein whose absence causes increased cell death during neurogenesis. It is essential for brain development makes 1.1 m
2. ASPM related to the development of the neo cortex in Africa before the appearance of h. sapiens
3. SHH related to the development of the motor system and may be related to bipedalism
4. FOXP2 would have allowed amplify initially associated functions to Broca's area (thereby facilitating the subsequent emergence of syntax and optimizing verbal memory and phonological processing). This phenomenon appeared 300,000 years ago
Among previous geological phenomenon the appearance of hominids highlight the Cenozoic glaciation (between 40 million and 10,000 years ago) that allowed "evolutionary bags" to open and close leaving scattered and isolated genetic groups of prehominids.
This phenomenon contributed to the cerebralization, corticalization and socialization of the future of the human species.
Among the genetic factors of our own species we highlight the loss of ability to synthesize vitamin C in our gut and mutations positioning of the sphenoid to increase cranial capacity.
As for the contemporary geological phenomenon to the most important human species that has influenced their selection and evolution highlight a volcanic winter lasting 6 years later the eruption of Toba (Sumatra) 73,000 years ago.
As a result the human population the human population was reduced to the point that it is considered that the Y chromosome of the human species has its origin in the stage of survivors.
We must also consider in this group the three ice ages that ended the Cenozoic glaciation: Age of Riss (180-130000 years), age Wurn (70-10000 years) and post-glacial period (10,000 years before present).
This phenomenon locked in small habitat loss coinciding with the synthesis of vitamin C, the human race became mandatory frugivore.