Here is a picture of the Egyptian Sphinx when its body was buried in sand circa 1860. If its head fell backward, it would look suspiciously like the infamous Face on Mars.
According to these more recent images taking last month the Face on Mars and its rocky neighbors look more like a plate of gold mash potatoes than an Egyptian valley, but it makes you wonder if, in deed, there are ruins of a great civilization buried on mars (and perhaps an undiscovered breed of first generation jambands!---sorry Max Creek).
While I don’t think an ancient race of Flintstones skirted around the universes building Sphinxes (if they did, they’d at least look like Betty Rubble), I have stumbled across at least one interesting theory. According to The Mars Mystery, and as quoted by Wikipedia, “...we have demonstrated with a substantial body of evidence that the pattern of stars that is "frozen" on the ground at Giza in the form of the three pyramids and the Sphinx represents the disposition of the constellations of Orion and Leo as they looked at the moment of sunrise on the spring equinox during the astronomical "Age of Leo" (i.e., the epoch in which the Sun was "housed" by Leo on the spring equinox.) Like all processional ages this was a 2,160-year period. It is generally calculated to have fallen between the Gregorian calendar dates of 10,970 and 88810 BC (op. cit., p.189)
Who knows, maybe before people had blogs, they built Sphinxes to waste time while they should be studying (or at least sleeping)