Mesoamerican calendars was of ritual significance to a number of Mesoamerican cultures. A third major calendar form known as the Long Count is found in the inscriptions of several Mesoamerican cultures, most famously those of the Maya civilization who developed it to its fullest extent during the Classic period (ca. 200–900 CE). The Long Count provided the ability to uniquely identify days over a much longer period of time, by combining a sequence of day-counts or cycles of increasing length, calculated or set from a particular date in the mythical past. Most commonly, five such higher-order cycles in a modified vigesimal (base-20)
History of the Americas This civilization is considered the mother culture of the Mesoamerican civilizations. The Mesoamerican calendar, numeral system, writing, and much of the Mesoamerican pantheon seem to have begun with the Olmec. Some elements of agriculture seem to have been practiced in Mesoamerica quite early. The domestication of maize is thought to have begun around 7,500 to 12,000 years ago. The earliest record of lowland maize cultivation dates to around 5100 BC. Agriculture continued to be mixed with a hunting-gathering-fishing lifestyle until quite late compared to other regions, but by 2700 BC, Mesoamericans were relying on maize, and living mostly in villages.