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..
The Roman Empire was among the most powerful economic, cultural, political and military forces in the world of its time. It was the largest empire of the classical antiquity period, and one of the largest empires in world history.he imperial successor to the Republic lasted approximately 500 years. The first two centuries of the Empire's existence were a period of unprecedented political stability and prosperity known as the Pax Romana, or Roman Peace.