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The ancient Maya city of Chichén Itzá in Mexico’s Yucatan Peninsula has long been associated with human sacrifice, with hundreds of bones unearthed from temples, a sacred sinkhole and other underground caves.
A long-standing misconception is that the victims were often young and female – an impression that has stuck in the contemporary imagination and has become difficult to dislodge even as later research has shown that both men and women were among those who were sacrificed as well as children. A study published Wednesday in the journal Nature adds unexpected detail to that 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 boys, many of whom were closely related.
“There were two big moments of surprise here,” said lead study author Rodrigo Barquera, a researcher in the Department of Archeology at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
“We were thinking, under the influence of traditional archeology that we would find, non-sexually biased burials or mostly girls,” he said.
“And the second (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
The lurid notion that the Maya only sacrificed young women or girls is largely a myth that arose from early and romantic accounts of Chichén Itzá’s sacred hole, or cenote, said Rubén Mendoza, an archaeologist and professor in the Department of in Social Sciences and Global Studies at California State University, Monterey Bay. He was not involved in the study but is the editor of a new book on ritual sacrifice in Mesoamerica.
“The characterization of Maya sacrifice was promoted through media depictions of young marriages (for example, virgins) being chased to death at the Holy Well,” he said by email.
However, the mystery of exactly who the Maya sacrificed has been difficult to solve because it is impossible to identify the sex of a child’s skeleton by analyzing bones alone.
Although the pelvis and some other bones can reveal whether the skeleton was male or female, the differences only become apparent during puberty and, even in adults, natural variation can be difficult to identify accurately.
This difficulty makes genetic analysis extremely 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 changed archeology in Europe and higher latitudes, is more limited in tropical areas because DNA degrades more easily in warmer conditions. However, recent advances in ancient DNA technology are expanding its reach, she said.
“We’re getting better and 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 so excited about that because this is an area of the world that has this incredibly rich history.”
Boys were younger than 6 when offered
The team behind the new study was able to extract and sequence ancient DNA from 64 out of around 100 people, whose remains were found scattered in a water cultun – an underground storage chamber discovered in 1967 about 400 meters (437 yards ) from the sacred borehole. in Chichén Itzá.
With radiocarbon dating, the team found that the underground cave was used for 500 years, although most of the children the team studied were buried between AD 800 and 1,000 — during the height of Chichén Itzá’s political power in the region .
All the children, drawn from the local Maya population at the time, were boys, according to the DNA analysis, and a quarter of them were closely related to at least one other child in the cult. The group also included two pairs of twins as well as siblings and cousins. Most of the boys were aged between 3 and 6 when they died.
Carbon and nitrogen version or isotope analysis in the bones also indicated that the related children had similar diets. Together, according to the authors, these findings suggested that related male children were likely to be selected in pairs for ritual sacrifices associated with the cult.
“It’s surprising to me to see family members, given the huge time span of the hoard, which is now confirmed by radiocarbon dating over a 500-year period in which these bodies were slowly accumulated,” said Vera Tiesler. , bioarchaeologist and professor at the Autonomous University of Yucatan, in an email. She was not involved in the research.
Although the study’s authors believe this finding represents the only known burial of male child sacrifice, Tiesler said the ancient Maya ritual calendar was complex, and likely contained “victim profiles” for different religious occasions. throughout the year and time cycles.
How to identify twins
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 of those, you can be sure we didn’t double sample anyone,” Warinner said. “And that’s what allowed us to identify identical twins.”
Twins have a special place in the origin stories and spiritual life of the ancient Maya, Warinner added, especially a story known as the “Hero Twin” in which two brothers enter the underworld to avenge the death of their father.
It is not clear how or exactly why the children were sacrificed, but the 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 imply, was completely different for us, because we have a very different view of the world than they did,” Barquera said. “For them, it was not losing a child, not losing one of their children, but an opportunity given by whatever forces to be part of this special burial.”
Warinner said the study is the first time genetic material recovered from ancient Maya remains has been detailed enough to be sequenced, giving a richer picture of who the victims were and who they were – and are – with. related to them.
The team compared the ancient DNA with 68 residents of the present-day Maya community of Tixcacaltuyub. The researchers found that the two had a close genetic identity.
“They were very happy to find out that they were related to the people who once lived on Chichén Itzá,” said Barquera.
The team also showed how the biological consequences of diseases brought by European colonists shaped the inhabitants’ immune systems. The researchers discovered that the local indigenous population today has genetic variants that could protect them from salmonella infection, which is thought to be the pathogen behind the disastrous 1545 cocoliztli epidemic.
María Ermila Moo-Mezeta, co-Mayan author of the study and research professor at the Autonomous University of Yucatan, said that the new analysis was significant for her, as a professor of Indigenous origin, to “preserve the historical memory of the Mayan people.”
It was interesting to learn how past suffering left a stamp on the immune system of today’s Maya communities, Tiesler said.
“This study is decidedly new; a starting point for further, more specific inquiry into the convoluted trajectory of the Maya,” she said.
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