Inca nobility at Machu Picchu relied on special, permanent servants from the far corners of the empire to manage the royal estate, according to a new study of human skeletons found buried at the site. Machu Picchu sits high in the Peruvian Andes about 50 miles (80 kilometers) northwest of the former Inca capital of Cusco (see map).
Royal retainers, known as yanacona, may have been brought to the site from as far away as South America's Pacific Coast, the northern highlands, and the area around Lake Titicaca near Peru's border with Bolivia, the study says.

Determining the geographic origins of yanacona may help researchers better understand how the Inca practice of paying tributes with labor helped shape the empire's social classes.