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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 recovered from temples, a sacred pit and other underground caves.
There is a long-standing misconception that victims are often young and female; This has become entrenched in today’s imagination, and this impression is becoming difficult to dislodge, even as more recent research suggests that the victims included both men and women, as well as children. A study published Wednesday in the journal Nature adds unexpected details to this more complex picture.
The new analysis, based on ancient DNA recovered from the remains of 64 people who archaeologists believe were ritually sacrificed and then deposited in an underground chamber, found that most of the victims were young boys, many of whom were close relatives.
“There were two moments of great surprise here,” said the study’s lead author, Rodrigo Barquera, a researcher in the department of archaeogenetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
“Influenced by traditional archaeology, we were thinking of a gender-neutral burial where mostly girls were buried,” he said.
“The second time was when we found out that some of them were related and there were two sets of twins.”
Analysis of skeletons can only reveal so much
Rubén Mendoza, an archaeologist and professor in the department of social sciences and global studies, said the terrifying idea that the Mayans sacrificed only young women or girls is largely a myth stemming from early and romantic accounts of the sacred pit, or cenote, of Chichén Itzá. California State University, Monterey Bay. He was not involved in the research but is the editor of a new book on ritual sacrifice in Mesoamerica.
“This characterization of Mayan sacrifice was brought to the fore by media depictions of young maidens (aka virgins) being thrown to their deaths at the Sacred Well,” he said via email.
But solving the mystery of exactly who the Mayans sacrificed has been difficult because it is impossible to determine the gender of a child’s skeleton by analyzing the bones alone.
Although the pelvis and several other bones reveal whether the skeleton is an adult male or female, differences in symptoms only appear during adolescence, and natural variation even among adults can make accurate identification difficult.
This challenge makes genetic analysis particularly valuable, said study co-author Christina Warinner, John L. Loeb Professor of Social Sciences and Anthropology at Harvard University and group leader at the Max Planck Institute for Evolutionary Anthropology. However, the impact of ancient DNA, which revolutionized archeology in Europe and higher latitudes, was more limited in tropical regions because DNA decomposes more easily in hot conditions. But recent advances in ancient DNA technology have broadened its scope, he said.
“We’re getting better at taking even 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 very excited about this because this is a part of the world with an incredibly rich history.”
The boys were under 6 years old when they were sacrificed
The team behind the new study managed to extract and sequence the ancient DNA of 64 of about 100 individuals whose remains were found scattered in a water chultún (an underground storage chamber discovered in 1967 about 400 meters (437 yards) from the sacred pit). In Chichén Itzá.
Using radiocarbon dating, the team determined that the underground cave had been used for 500 years; However, most of the children whose remains the team examined were interred there between 800 and 1000 AD, when Chichén Itzá was at the height of its political power in the region.
According to DNA analysis, all of the children were boys taken from the local Mayan population at the time, and at least a quarter of them were closely related to at least one other child in chultun. 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 variants, or isotopes, of carbon and nitrogen in the bones also revealed that the children involved had similar diets. According to the authors, these findings suggest that related sons were likely selected in pairs for sacrifices associated with chultún.
“It is surprising to me to see the family members, given the enormous time span of the bed, which has been confirmed by radiocarbon dates to have been used over a 500-year period, during which the bodies gradually accumulated,” Vera Tiesler said. bioarchaeologist and professor at the Autonomous University of Yucatán in an email. She was not involved in the research.
While the study authors believe this finding reveals the only known burial of sacrificed boys, Tiesler said the ancient Mayan ritual calendar was complex, likely containing different “sacrifice profiles” for different religious events across years and time cycles.
How were the twins identified?
To avoid taking samples from the same child twice, the team used the same bone (the stony bone at the base of the skull) from each child.
“Since each child only has one of these, you can rest assured that we never sampled any individual twice,” Warinner said. “And that’s actually what allows us to identify identical twins.”
Warinner added that twins hold a special place in the origin stories and spiritual life of the ancient Maya, especially the story called “Hero Twins,” in which two brothers descend into the underworld to avenge their father’s death.
It is unclear how and exactly why children were sacrificed, but sacrificial methods used at the time included decapitation and removal of the heart.
“I think we need to remember that death and everything that these rituals imply is completely different for us because we have a very different worldview than theirs,” Barquera said. “For them, it wasn’t about losing a child or losing one of their children, it was an opportunity given by whatever powers that be to be a part of this special funeral.”
Warinner said the study is the first time genetic material from ancient Mayan ruins has been detailed enough to be sequenced, providing a richer picture of who the victims were and who they were related to.
The team compared the ancient DNA to that of 68 residents of the modern-day Maya community of Tixcacaltuyub. The researchers found that the two shared a close genetic signature.
“They were very happy when they learned that they were related to the people who once lived in Chichén Itzá,” Barquera said.
The team also showed how residents’ immune systems were shaped by the biological consequences of diseases brought by European colonists. Researchers have found that today’s local indigenous population has genetic variants that may protect them against infection with salmonella, thought to be the pathogen behind the devastating 1545 cocolith epidemic.
María Ermila Moo-Mezeta, Maya co-author of the study and a research professor at the Autonomous University of Yucatán, said the new analysis was important to her, as a professor of Indigenous descent, for preserving the “historical memory of the Maya people.”
Tiesler added that it is fascinating to learn how past suffering left its mark on the immune system of today’s Mayan communities.
“This study is absolutely new; “It’s a starting point for further, more specific research into the complex course of yeast,” he said.
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