MONTREAL, Quebec, Jan. 29 -- McGill University issued the following news release: * * * Remote sensing tools yield insights into abandoned pre-Columbian Mexican city Awareness of the Zapotecs' level of political and social organization stands to shed light on their level of agency in negotiating with the Spanish A McGill University researcher has discovered that Guiengola, a 15th century Zapotec site in southern Oaxaca, Mexico, which had been thought to be simply a fortress where soldiers we more PR