Human remains are rare near Machu Picchu, and the wet mountain climate makes textiles uncommon finds, said Cock, who was not part of the research team.
"Finding organic material in the mountains is significant because it's so scarce," he said. "The humidity from rain decomposes individuals and textiles."
Analysis of the bones should also reveal age at death, sex, cause of death, diet, and perhaps even the dead's occupations, Astete added.
"We should be able to tell whether these people carried large burdens to help construct terraces, for example. Their bones will be bent, not straight. They will have deformities," he explained.
"Bones will also tell us about their diets and diseases. A fracture would reveal an accident."
The burial of human remains held special significance for the Inca, added Huarcaya, the lead researcher.
"The remains in tombs are like the guardians of the population in Andean ideology," he said. "For [ancient Andeans], death does not exist."
Machu Picchu Revealed
Built around 1460, the city of Machu Picchu seems to have been abandoned after the Spanish conquest in the 1500s, though it was never found by the conquerors.
Yale archaeologist Hiram Bingham brought Machu Picchu to worldwide attention after local Indians led him to the site in 1911. (See Bingham's original photos of Machu Picchu from his expedition.)
The new discoveries promise to shed light on the mystery of the ancient city and its role within the Inca Empire, Cock said.
"We know Machu Picchu, but we don't know its surrounding areas," he said.
"I think new material will be found that will help us understand the Inca's relationship with the region."