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The ancient Mayan city of Chichén Itzá on Mexico’s Yucatán Peninsula has long been associated with human sacrifice, with hundreds of bones excavated from temples, a sacred sinkhole and other underground caverns.
A long-held misconception is that the victims were often young and female – an impression that has stuck in the contemporary imagination and has become difficult to dispel, even though more recent research has suggested that the victims included both men and women, as well as children. A study published Wednesday in the journal Nature adds unexpected details to that more complex picture.
The new analysis, based on ancient DNA from the remains of 64 people who archaeologists say were ritually sacrificed and then deposited in an underground chamber, found that the victims were all young boys, many of whom were closely related.
“There were two big moments of surprise here,” says lead study author Rodrigo Barquera, a researcher in the department of archaeogenetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
“We thought, influenced by the traditional archeology that we would find, that there would be a burial that was not gender-focused, or especially girls,” he said.
“And the second (was) when we found out that some of them were related and that there were two twins.”
Analysis of skeletons can only reveal so much
The grim idea that the Mayans sacrificed only young women or girls is largely a myth rooted in early and romantic stories about the sacred sinkhole or cenote of Chichén Itzá, says Rubén Mendoza, an archaeologist and professor in the department of social sciences and global sciences. studies from California State University, Monterey Bay. He was not involved in the research, but is editor of a new book on ritual sacrifice in Mesoamerica.
“This characterization of Mayan sacrifice was catapulted to prominence by media images of young girls (also called virgins) being hurled to their deaths at the Sacred Spring,” he said via email.
However, the mystery of who exactly the Mayans sacrificed is difficult to untangle, as it is impossible to identify the gender of a child’s skeleton by analyzing the bones alone.
Although the pelvis and a few other bones can reveal whether the skeleton was 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 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 at higher latitudes, is more limited in tropical regions because DNA breaks down more easily in warm conditions. However, recent developments in ancient DNA technology are expanding its reach, she said.
“We are getting better at recovering even very small amounts of DNA. And suddenly we now have the opportunity to do these large-scale genomic studies and apply ancient DNA as a tool to help us understand the past in Central America,” Warinner said. “I’m so excited about that because this is a part of the world with an incredibly rich history.”
Boys were younger than 6 when they were sacrificed
The team behind the new study was able to extract and sequence ancient DNA from 64 of approximately 100 individuals, whose remains were found scattered in a water chultún – an underground storage chamber discovered in 1967 about 400 meters from the sacred sinkhole . in Chichen Itzá.
Using radiocarbon dating, the team found that the underground cavern was used for 500 years, although most of the children whose remains the team studied were buried there between 800 and 1000 AD – during the height of Chichén Itzá’s political power in the region.
All the children were boys, who according to DNA analysis at the time came from the local Mayan population, and at least a quarter of them were closely related to at least one other child in the chultún. The group also included two sets of twins, siblings and cousins. Most boys were between 3 and 6 years old when they died.
Analysis of variants, or isotopes, of carbon and nitrogen in the bones also suggested that the related children had similar diets. According to the authors, these findings together suggested that related male children were likely selected in pairs for ritual sacrifices associated with the chultún.
“It is surprising to me to see family members, given the enormous time span of the deposition, which has now been confirmed by radiocarbon dating to have been used over a 500-year time frame, during which these bodies slowly accumulated,” says Vera Tiesler. , a bioarchaeologist and professor at the Autonomous University of Yucatán, in an email. She was not involved in the investigation.
Although the study authors believe this finding 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 time cycles.
How twins were identified
To avoid sampling the same child twice, the team used the same bone from each child: the petrous bone at the base of the skull.
“Since each child only has one, you can be sure we haven’t double-checked any person,” Warinner said. “And that allowed us to identify identical twins.”
Twins hold a special place in the origin stories and spiritual lives of the ancient Mayans, Warinner added, especially in a story called the “Hero Twins,” in which two brothers descend to the underworld to mourn the death of their father. avenge.
It is not clear exactly how and why the children were sacrificed, but sacrificial methods used at the time included decapitation and removal of the heart.
“I think we have to remember that death, and everything that these rituals entail, was completely different for us, because we have a very different view of the world than they do,” Barquera said. “For them it was not losing a child, not losing one of their children, but an opportunity presented by whatever forces were available to be part of this special funeral.”
Warinner said the study marked the first time that genetic material from ancient Mayan remains was detailed enough to be sequenced, creating 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 current Mayan community of Tixcacaltuyub. The researchers found that the two shared a close genetic signature.
“They were thrilled to hear that they were related to the people who once inhabited Chichén Itzá,” Barquera said.
The team also showed how residents’ immune systems had been shaped by the biological effects of diseases brought with them by European settlers. The researchers found that local indigenous people today have genetic variants that may have protected them from Salmonella infection, believed to be the pathogen behind the devastating Cocoliztli epidemic of 1545.
María Ermila Moo-Mezeta, a Mayan study co-author and research professor at the Autonomous University of Yucatán, said the new analysis was important to her, as a professor of indigenous descent, to understand the “historical memory of the Mayan people’.
It was fascinating to see how past suffering had left an imprint on the immune systems of today’s Mayan communities, Tiesler added.
“This study is definitely new; a starting point for further, more specific research into the complex trajectory of the Maya,” she said.
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