Other ideas Morley put forward include the proposal that the ancient Maya were the first in Mesoamerica to domesticate maize ("Zea mays" ssp. "mays"), with the wild variety known as "teosinte" being its progenitor. Recent genetic studies have shown Morley to be largely correct in this, although the beginnings of its domestication (12,000 to 7,500 years ago) pre-dates the establishment of anything resembling Maya society. In general, Morley held that the ancient Maya had been the pre-eminent civilization of Mesoamerica, from which other cultures had drawn their influences. It is now accepted that other societies (such as the Zapotec and Olmec) preceded that of the Maya and the influences—such as development of writing and the Mesoamerican calendars—were rather the other way around; even in the later stages of Maya history, their region came under significant influences drawn from central Mexico, such as the Toltec "invasion". However, the Maya did also exert a widespread influence over neighboring contemporary cultures, one which was significant and not to be overlooked.