Dozens of their skulls and cave writings have been found dating back to 50,000 years.
Olmec Head dated circa 1,600 BC[size=15pt]We know they were the builders of ancient American pyramids.Two Mexican sites continue years after their excavation to be proposed as valid pre-Clovis sites. Lorenzo and Mirambell (199) recently concluded that "these dates provide clear evidence of human activity at the site about 22,000 years ago." At the site a prismatic obsidian blade found under a tree trunk dated to 23,950 950 years B. was obsidian hydration dated to between 21,250 and 25,000 years B. P., a circular scraper manufactured from microcrystalline quartz by direct percussion (Lorenzo and Mirambell 191).At Tlapacoya, Mexico, presumed hearths associated with animal bone middens were dated to 24,000 4000 and 21,700 500 years B. A limestone core was recovered from a stratum dated at 15,000 years B.Many of us learned that rhyme, part of a longer history poem when being taught in school that Christopher Columbus discovered America.Although nothing can be taken away from Columbus' daring voyage, he certainly was not the first to arrive on the shores of the Americas.The discovery raised tantalizing questions that came to haunt Sutherland and drive more than a decade of dogged scientific sleuthing.