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The ancient Mayan city of Chichén Itzá on Mexico’s Yucatan Peninsula has long been associated with human sacrifice, with hundreds of bones unearthed from temples, a sacred hole and other underground caves.
A long-standing misconception is that the victims were often young and women – an impression that has seared itself into the contemporary imagination and which has become difficult to dislodge, even as more recent research has suggested that both men and women were among those sacrificed, as well as the children. A study published Wednesday in the journal Nature adds unexpected details to this more complex picture.
The new analysis, based on ancient DNA from the remains of 64 people who archaeologists believe were ritually sacrificed and then deposited in an underground chamber, found that the victims were all young men, many of whom were close relatives.
“There were two big moments of surprise here,” said the study’s lead author, Rodrigo Barquera, a researcher in the archaeogenetics department at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
“We were thinking, influenced by traditional archaeology, that we would find a burial without sexual prejudice or mainly girls,” he said.
“And the second (was) when we found out that some of them were related and there were two sets of twins.”
Skeletal analysis can only reveal so much
The sinister notion that the Mayans sacrificed only women or young girls is largely a myth that originated from early, romantic accounts of the sacred sinkhole, or cenote, of Chichén Itzá, said Rubén Mendoza, an archaeologist and professor in the department of social sciences. and global studies from California State University, Monterey Bay. He was not involved in the study, but is an editor for a new book on ritual sacrifice in Mesoamerica.
“This characterization of Mayan sacrifice was catapulted to the forefront through media depictions of young maidens (also known as virgins) being thrown to their deaths in the Sacred Well,” he said in an email.
However, the mystery of who exactly the Mayans sacrificed has been difficult to unravel because it is impossible to identify the sex of a child’s skeleton just by analyzing the bones.
Although the pelvis and some other bones can reveal whether the skeleton was that of an adult male or female, the telltale differences only emerge during puberty, and even among adults, natural variation can make accurate identification difficult.
This difficulty makes genetic analysis particularly valuable, said study co-author Christina Warinner, John L. Loeb Associate Professor of Social Sciences and Anthropology at Harvard University and group leader at the Max Planck Institute for Evolutionary Anthropology. But the impact of ancient DNA, which revolutionized archeology in Europe and higher latitudes, has been more limited in tropical areas because DNA degrades more easily in hot conditions. However, recent advances in ancient DNA technology are expanding its reach, she said.
“We are getting better at recovering very small amounts of DNA. And suddenly, we now have the ability to do these large-scale genomic studies and apply ancient DNA as a tool to help us understand the past in Mesoamerica,” Warinner said. “I’m really excited about this because this is an area of the world that has an incredibly rich history.”
The boys were under 6 years old when they were euthanized
The team behind the new study was able to extract and sequence ancient DNA from 64 of the approximately 100 individuals whose remains were found scattered in a water chultún – an underground storage chamber discovered in 1967, about 400 meters (437 yards) away. ) of the sacred sinkhole. in Chichén Itzá.
Using radiocarbon dating, the team discovered that the underground cave was used for 500 years, although most of the children whose remains the team studied were buried there between 800 and 1,000 AD – during the height of Chichén Itzá’s political power in region.
All of the children were boys, drawn from the local Mayan population at the time, according to DNA analysis, and at least a quarter of them were close relatives of at least one other child from the chultún. The group also included two sets of twins, as well as siblings and cousins. Most of the boys were between 3 and 6 years old when they died.
Analysis of carbon and nitrogen variants or isotopes in the bones also suggested that related children had similar diets. Together, the authors said, these findings suggested that related male children were likely selected in pairs for ritual sacrifices linked to chultún.
“It is surprising for me to see members of the family, given the enormous temporal extent of the deposit, which by radiocarbon dates is now confirmed to have been used over a 500-year period during which these bodies slowly accumulated,” said Vera Tiesler . , bioarchaeologist and professor at the Autonomous University of Yucatán, via email. She was not involved in the research.
Although the study authors believe this discovery reveals the only known burial of sacrificed male children, Tiesler said the ancient Mayan ritual calendar was complex, likely with different “victim profiles” for different religious occasions throughout the year and periods. temporal cycles.
How the twins were identified
To avoid sampling the same child twice, the team used the same bone from each child – the petrosal bone at the base of the skull.
“Since each child only has one of these, you can be sure that we did not double-sample any individuals,” Warinner said. “And that’s what allowed us to identify identical twins.”
Twins hold a special place in the origin stories and spiritual lives of the ancient Maya, Warinner added, particularly a story called “Hero Twins,” in which two brothers descend into the underworld to avenge their father’s death.
It is unclear how or exactly why the children were sacrificed, but the sacrificial methods in use at the time included decapitation and removal of the heart.
“I think we have to remember that death and everything that these rituals entail were completely different to us, because we have a very different worldview than they had,” Barquera said. “For them, it wasn’t losing a child, it wasn’t losing one of their children, but an opportunity given by whatever forces to be part of this special burial.”
Warinner said the study was the first time that genetic material recovered from ancient Mayan remains was detailed enough to be sequenced, providing a richer picture of who the victims were and who they were — and are — related to.
The team compared the ancient DNA with that of 68 residents of the present-day Mayan community of Tixcacaltuyub. The researchers found that the two shared a close genetic signature.
“They were very happy to learn that they were related to the people who inhabited Chichén Itzá,” said Barquera.
The team also showed how residents’ immune systems were shaped by the biological consequences of diseases brought by European colonizers. Researchers discovered that the local indigenous population now has genetic variants that may have protected them against salmonella infection, believed to be the pathogen behind the devastating cocoliztli epidemic of 1545.
María Ermila Moo-Mezeta, Mayan co-author of the study and research professor at the Autonomous University of Yucatán, said the new analysis was significant for her, as a professor of indigenous origin, to preserve the “historical memory of the Mayan people.”
It was fascinating to learn how past suffering left a mark on the immune systems of today’s Mayan communities, Tiesler added.
“This study is decidedly new; a starting point for future, more specific investigations into the complicated trajectory of the Maya,” she said.
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