If your son was captain of the high school football team around 2,000 years ago, the mantle in your living room might look something like this: blue ribbon, gold medal, championship trophy, severed head from the opposing team on a string. Historians, archaeologists, scientists, and people with interesting hobbies have long known that the ancient South American culture responsible for the Nazca Lines in the highlands of Peru collected human heads as trophies. What is noteworthy about a new study coming out of the Chicago Field Museum is that it found that the heads were lopped off the necks of people who lived in the same place and belonged to the same group as the culture who went head-hunting.
To find out where the victors and the beheaded were each from, scientists took inspiration from the old maxim, "you are what you eat." Researchers tested tooth enamel samples from 16 trophy heads housed in the Field Museum and 13 mummified bodies buried in the Nazca region. Due to the arid nature of the Nazca landscape, archaeologists found the skulls amazingly well-preserved (some still had hair on them). Three common elements in the samples—strontium, oxygen, and carbon—display subtly different atomic structures that vary by geographic location. For example, the isotope ratio in your bones parallels the age of the bedrock where the food you eat is grown. Using this "chemical signature," scientists could map out the origins of their mummies and the map made it clear that the hunter and the hunted were neighbors.
Theories as to the purpose of the head trophies in ancient life have been batted around in anthropological circles for decades. They include use in fertility rites, a prize from war opponents, and a sign of respect for and remembrance of ancestors. Ancient pottery uncovered from nearby sites shows these cranium trophies in the context of agricultural fertility, alongside warriors, and being held by mythical creatures. The hole drilled into the skulls means they were suspended with string, but where they were hung and why remains a mystery. At any rate, don't think you get your skull back on your way out—anthropologists have found the severed heads buried next to their collectors, not with the owners.
Understanding why the Nazca collected trophy heads could be key to understanding their civilization—how it was organized and how it progressed. Was neighbor fighting neighbor? Was this a religious ritual people entered into voluntarily? The answers could also reveal much about South American politics and how the region's early political system developed. The Nazca tribe was small, agrarian, and independent, but was eventually taken over by an empire with wide-reaching power and rulers governing from afar. The better the understanding of Nazca culture and rites, the better the understanding of how this transition came about, and the debate, so to speak, has really come to a head.
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