Why don’t we all have blue eyes, or brown?
How did those colors evolve? Could there have been a Homo Erectus with blue/green eyes?
And how long will it be before the blue-eyed go extinct?
Asker: Alexandra, 15 years old
Answer
The color of your eyes is genetically determined by several genes. These genes play a role in the production of pigment and the amount of pigment helps determine the color of your eyes.
The combination of those genes results in a combination of color shades. We have different eye color because these genes have spread through the population.
It is believed that only brown eyes existed before and that the first blue eyes appeared about ten thousand years ago. Those blue eyes have spread rapidly across Europe and especially the Scandinavian countries. This may be due to the preference of a partner with blue eyes (and possibly blond hair). The development of blue eyes is due to mutations in the pigment-producing genes.
Homo erectus lived until about 400,000 years ago and so almost certainly had dark eyes.
The blue-eyed ones probably won’t die out, just like green-, brown- or gray-eyed ones.
Answered by
dr. Pieter Stragier
Molecular Microbiology Biomedical Sciences Medical and Pharmaceutical Research Molecular Biotechnology
university of Ghent
http://www.ugent.be
.