Countdown to sacrifice

Posted 2 October 2007

Child victims selected by the Incas for ritual killing were fed a special diet to elevate their social status in a yearlong “countdown to sacrifice,” scientists find in a new study published in PNAS
 

Tom Gilbert from University of Copenhagen is part of an international research team that has analysed samples of hair taken from the scalps of four child mummies, found on some of the highest peaks of the southern Andes. (The Incas chose mountaintops for sacrifices to appease the weather gods.)

Because hair consists of nonliving keratin that is not supplied with new nutrients, it provides a record of a person’s diet and environment. The scientists measured the isotopic ratios of hydrogen, oxygen, carbon, nitrogen, and sulfur. Differences in these ratios indicate the type of food eaten and its geographic origin.

Beginning a year before death, isotopic values indicate that the victims had begun to eat a diet richer in meat and in maize, a higher-status plant. The hair-strands also provide evidence of a long trek from the royal city of Cuzco to the remote mountaintop where the sacrifice took place.

Last week, Tom Gilbert published an article in Science about a new and more precise method for analysing DNA from hair:

Read more about the method for analysing DNA