The Nature of Consciousness

Piero Scaruffi

(Copyright © 2013 Piero Scaruffi | Legal restrictions )
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These are excerpts and elaborations from my book "The Nature of Consciousness"

Genetic Fossils

Genomes have confirmed the theory of evolution.  In the 1950s the Italian biologist Luigi Cavalli-Sforza first had the idea that one could use genetic information to trace the genealogical tree of species. Genomes share common parts and different species are determined by the branching out of the other parts.  The genealogical tree of living beings is carefully reflected in the structure of their genomes. The genome of a species is almost a "memory" of that species' evolutionary journey.  Most human genes, for example, date back to primitive organisms, and they are shared by all modern animals that descend from those organisms. Only a few can be said to be truly "human".

Basically, an organism’s DNA is a record of its evolutionary past. Each living organism “is” a fossil. The same principle helped biologists such as Allan Wilson in the 1980s study the evolution of humans. He focused on mitochondria, the part of the cell that converts sugar into energy. They have their own DNA. This DNA can be used as a “molecular clock” by estimating the number of its mutations.

Because mitochondria are inherited only from the mother, they can only be used to construct a matrilineal genealogical tree. Thus it was derived that all living humans are descendants of one woman who lived about 150,000 years ago. The molecular clock for the patrilineal genealogical tree is a piece of the Y chromosome, which is inherited only by sons from their father. Thus it was derived that all living humans are descendants of a man who lived about 60,000 years ago.

 


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