Ancient Mayan human sacrifices involved twins

New DNA analysis also contradicts some early colonial Spanish accounts.
Andrew Paul Avatar
Detail from the reconstructed stone tzompantli, or skull rack, at Chichén Itzá.
Detail from the reconstructed stone tzompantli, or skull rack, at Chichén Itzá. Christina Warinner

Although Mayan written sources clearly document human sacrificial rituals, many details about the Mesoamerican civilization’s ceremonial victims remain unknown. Thanks to new genetic analysis, however, archeologists are piecing together the intricate religious and agricultural rites—and they are as revealing as they are grim.

Centrally located in the northern Yucatán Peninsula, Chichén Itzá is considered one of the most expansive, well-preserved archeological sites of Mayan society. First established during the Late Classic period (600-800 CE), the city over time became one of the region’s most significant cultural and political centers, eventually reaching its apex around the 11th century CE. Chichén Itzá’s political relevance would decline in the coming centuries, but it still remained a cultural and religious hub during that time. The arrival of European forces in the 1500’s, however, quickly brought about the civilization’s collapse through a mixture of violence and disease.

 El Castillo, also known as the Temple of Kukulcan, is among the largest structures at Chichén Itzá and its architecture reflects its far-flung political connections.
 El Castillo, also known as the Temple of Kukulcan, is among the largest structures at Chichén Itzá and its architecture reflects its far-flung political connections. Credit: Johannes Krause

In 1967, archeologists uncovered remnants of a chultún, or underground cistern, in Chichén Itzá that Mayans appeared to have repurposed as a burial chamber containing over 100 young individuals. Although colonial Spanish accounts indicate human sacrifice victims were often young women and girls kidnapped from regions as far away as Honduras and Central Mexico, modern historians and experts would theorize for years about the sacrificial victims’ identities and origins. Details about their sex could not be ascertained from osteological analysis alone—but new genetic data analysis indicates some key revisions to the theories.

As detailed in a study published June 12 in Nature, researchers from Germany’s Max-Planck Institute for Evolutionary Anthropology recently examined genomic materials obtained from the skeletal remains from 64 of the individuals interred within the underground chamber. Their results expand—and correct—many previous assumptions.

For starters, all 64 bodies were biologically male, providing further evidence that many sacrifices included young men and women. Additionally, a quarter of those victims were closely related to each other—included two sets of twins.

[Related: Plants detected in ancient Mayan ‘ballcourts’ point to a sacred spot.]

“[S]acrificed children may have been specifically selected for their close biological kinship,” the authors write. “Moreover, this may underestimate the true number of relatives present in chultún as only 64 of the estimated 106 individuals in the chultún had a preserved petrous portion of the left temporal bone available for analysis.”

Portion of reconstructed stone tzompantli, or skull rack, at Chichén Itzá.
Portion of reconstructed stone tzompantli, or skull rack, at Chichén Itzá. Credit: Johannes Krause

According to the archeologists, this points towards a tendency for sacrifices to involve closely related young people more often than previously believed—likely because ritual children sacrifice is theorized to have been tied to crop yields and rainfall. Additionally, twins are an important motif within Mayan mythology, which also might explain their inclusion in the burial cavern.

“Twins feature prominently in Mayan and broader Mesoamerican mythology, where they embody qualities of duality among deities and heroes,” researchers explain in their study. “‘[B]ut until now they had not been identified in ancient Mayan mortuary contexts.”

Researchers then enlisted the aid of 68 present-day Maya locals living in Tixcacaltuyub, a town near Chichén Itzá. After comparing their genetic information with both the skeletal remains as well as ancient and modern regional data, they determined the existence of “a long-term genetic continuity in the Maya region,” indicating human sacrificial victims were more likely obtained locally than from farther away, as colonizers previously claimed. Further examinations located genetic variations associated with an immunity to certain infectious pathogens like Salmonella, which plagued the area during the Spanish colonial era.

Understanding these cultural and historic contexts allows archeologists to better grasp some of the region’s most pivotal civilizational shifts, as well as how their genetic effects linger to this day.