The Olmec culture existed from roughly 1200 BCE to 400 BCE. The idea that the Olmecs are related to Africans was suggested by José Melgar, who discovered the first colossal head at Hueyapan (now Tres Zapotes) in 1862. More recently, Ivan Van Sertima speculated an African influence on Mesoamerican culture in his book "They Came Before Columbus" (1976). His claims included the attribution of Mesoamerican pyramids, calendar technology, mummification, and mythology to the arrival of Africans by boat on currents running from Western Africa to the Americas. Heavily inspired by Leo Wiener (below), Van Sertima suggests that the Aztec god Quetzalcoatl represented an African visitor. His conclusions have been severely criticized by mainstream academics and considered pseudoarchaeology.