The Sphinx was built around 10,500 BC, and marks the BEGINNING of CIVILIZATION (as per the world of Anthropology, this is when and where civilization first started). At that time, the area was moist and tropical, today it is desert. The ancient egyptian civilization, lasted 10,000 years. Anthropolists agree, that mankind is not getting any smarter, the reason for recent technological advances are "greater population, leading to greater communications", and there is evidence that the ancients may have had a more advanced technology, that we originally thought (including electronics), but its all lost with time, dust in the winds of the desert
Pictured is the Sphinx, with a background of light (NASA photo) of the "Dog Star" and its "Companion Star" (only recently discovered). A tribe in Africa had ancient legends about the Dog Star, they said there were 3 Stars, and they were right, not only can we now see the 2nd one, Astronomers have recently detected and verified the 3rd Star.