While UV rays can cause skin cancer, because skin cancer usually affects people after they have had children, it likely had little effect on the evolution of skin color because evolution favors changes that improve reproductive success.
The only problem was that I couldn't remember where I had heard that. In fact, I wasn't all that sure that I was right. I know that the Roman Empire lasted rougly 500 years but how about the Egyptians, the Chinese, the Ottomons, etc. I thought that it would be interesting to explore different empires and see how long they lasted. In another article, I talk about the definition of civilization..
Over the 1,200 years of her history, ancient Rome had three forms of government: a monarchy for 244 years (753-509 BC), a republic for 482 years (509-27 BC) and rule by empero â¦ rs for 503 years (27 BC-476 AD).