The first populations inhabiting the present-day Metropolitan Area of Bogotá were hunter-gatherers in the late Pleistocene. The oldest dated evidence thus far has been discovered in "El Abra" (12,500 BP), north of Zipaquirá. Slightly later dated excavations in a rock shelter southwest of the city in Soacha provided ages of ~11,000 BP; Tequendama. Since around 0 AD, the Muisca domesticated guinea pigs, part of their meat diet. The people inhabiting the Bogotá savanna in the late 15th century were the Muisca, speaking "Muysccubun", a member of the Chibcha language family. Muisca means "people" or "person", making "Muisca people", how they are called, a tautology. At the arrival of the Spanish conquistadores, the Muisca population was estimated to be half a million indigenous people on the Bogotá savanna, and up to two million in the Muisca Confederation. They occupied the highland and mild climate flanks between the Sumapaz Mountains to the southwest and Cocuy's snowy peak to the northeast, covering an approximate area of , comprising Bogotá's high plain, a large portion of the modern-day department of Boyacá department portion and a small area in the Santander region.