Cacao trees originated in river valleys of South America and, by the seventh century AD, the Mayan Indians had brought them north into Mexico. Apart from the Mayans, many other Central American Indians including the Aztecs and the Toltecs seem to have at first domesticated and then cultivated cacao trees, and the word chocolate (the beverage) derives from xhocolatl (approximate spelling) or cacahuatl, both originating from the Aztec language. There are several mixtures of cacao described in ancient texts, for ceremonial, medicinal and culinary purposes. Some mixtures included maize, chili, vanilla (Vanilla planifolia), peanut butter and honey. Archaeological evidence of the use of cacao, while relatively sparse, has come from the recovery of whole cacao beans in Uaxactun, Guatemala and from the preservation of wood fragments of the cacao tree at the Belize sites (ex British Honduras). In addition, analysis of residues from ceramic vessels has found traces of theobromine and caffeine in early formative vessels from Puerto Escondido, Honduras (1100-900 BC) and in middle formative vessels from Colha, Belize (600-400 BC) , .