The structure is underground, carved from limestone by hands that worked the Yucat\u00e1n Peninsula’s bedrock centuries before anyone now living was born.<\/p>\n
A chult\u00fan \u2014 the Maya term for a subterranean chamber, typically bottle-shaped or roughly cylindrical, dug into the porous rock beneath the surface \u2014 sits near one of the most studied archaeological sites in the Western Hemisphere.<\/p>\n
Chich\u00e9n Itz\u00e1, the great Classic and Terminal Classic Maya city that rose to regional dominance over the course of centuries and whose iconic stepped pyramid, El Castillo, draws more than a million visitors each year, is surrounded by a landscape that still yields new information about the people who built it.<\/p>\n
This chult\u00fan was not a new discovery when researchers turned to it with the tools of ancient genomics.<\/p>\n
The bones of children had been found there before, catalogued and studied by archaeologists using the methods their field had developed.<\/p>\n
The burial had been interpreted as ritual in character, connected in some way to the religious life of a society that has attracted both genuine scholarship and significant misunderstanding in the centuries since Spanish colonizers first encountered Maya civilization.<\/p>\n
What ancient DNA made possible in this context was a transformation in the quality and type of questions the evidence could answer.<\/p>\n
Researchers generated genome-wide data from 64 subadult individuals whose skeletal remains had been recovered from the chult\u00fan.<\/p>\n
The individuals came from a feature located near Chich\u00e9n Itz\u00e1’s Sacred Cenote \u2014 the great natural well that served as a site of ritual significance and that has itself produced substantial evidence of past ceremony.<\/p>\n
The analysis was published in the journal Nature in 2024, and its findings challenged assumptions, confirmed some existing interpretations, and opened new questions that the science alone cannot yet answer.<\/p>\n
Within the first hours of reading the study, the headline finding is clear: all 64 analyzed individuals were genetically male.<\/p>\n
Not some of them.<\/p>\n
Not most of them.<\/p>\n
Every single one of the children whose ancient DNA could be read was genetically male.<\/p>\n
That finding, by itself, was remarkable.<\/p>\n
Osteological sex estimation \u2014 determining the biological sex of an individual from skeletal remains \u2014 is reliable in adults, where the pelvis and other bones carry measurable differences between sexes.<\/p>\n
In children, particularly young children, those differences are far less pronounced.<\/p>\n
Juvenile skeletal remains are difficult to sex with confidence from bone morphology alone, and the children in this chult\u00fan appear to have been young \u2014 subadults rather than teenagers or adults.<\/p>\n
<\/p>\n
The precision that genetics provides was not available from the bones themselves.<\/p>\n
So the sex finding, absolute in the genetic data, was the first thing the ancient DNA told the world that nothing else could have established with the same certainty.<\/p>\n
Sixty-four genetically male children, held in an underground limestone chamber near the heart of one of the Maya world’s most important cities.<\/p>\n
And then kinship analysis changed the picture again.<\/p>\n
Researchers examined the genetic data for signals of biological relatedness among the 64 individuals.<\/p>\n
What they found was that 11 pairs of the analyzed children showed evidence of being close relatives \u2014 first-degree or second-degree relatives \u2014 based on the patterns of DNA they shared.<\/p>\n
Among those 11 pairings, two were something even more specific: pairs of monozygotic twins.<\/p>\n
Identical twins.<\/p>\n
Two sets of them, in the same subterranean burial, from the same archaeological context at Chich\u00e9n Itz\u00e1.<\/p>\n
The statistical improbability of that is worth pausing on.<\/p>\n
Identical twins occur in roughly three to four births per thousand in populations that do not use modern fertility treatments.<\/p>\n
Finding one pair of identical twins among 64 individuals is already notable.<\/p>\n
Finding two pairs in the same archaeological assemblage, in the same specific location within a major ceremonial city, raises questions that genetics can identify but cannot, by itself, answer.<\/p>\n
Who were these children?<\/p>\n
<\/p>\n
Why were they here?<\/p>\n
Why were they all male?<\/p>\n
Why were so many of them related to each other?<\/p>\n
And what does the presence of identical twins, in a culture that invested deep symbolic significance in the concept of twinhood, mean for understanding the rituals that brought them to this underground chamber?<\/p>\n
The City and the Underground<\/p>\n
Chich\u00e9n Itz\u00e1 is a large and complex archaeological site, covering approximately five square kilometers of studied area within a broader settlement landscape that extended considerably farther.<\/p>\n
The city’s most prominent period of development and influence is generally associated with the Terminal Classic era, roughly from 800 to 1000 CE, though occupation of the area extended both earlier and later.<\/p>\n
<\/p>\n
At its height, Chich\u00e9n Itz\u00e1 was one of the largest cities in Mesoamerica, a center of political power, trade, and religious activity that drew people and resources from across the northern Maya lowlands and beyond.<\/p>\n
The architectural complex is dominated by several major structures.<\/p>\n
El Castillo \u2014 formally known as the Temple of Kukulc\u00e1n \u2014 is the stepped pyramid at the site’s center, its astronomical alignment designed so that during the equinoxes, shadows create the visual effect of a serpent descending its northern staircase.<\/p>\n
The Great Ball Court, one of the largest in the Maya world, stands to the northwest.<\/p>\n
The Temple of the Warriors, the Platform of the Eagles and Jaguars, the Group of a Thousand Columns: these are the monumental public architecture of a city that organized its built environment to communicate power, cosmology, and collective identity.<\/p>\n
<\/p>\n
And beneath the surface, the limestone landscape of the Yucat\u00e1n hides its own architecture.<\/p>\n
The peninsula sits on a vast carbonate platform that has been shaped by water over millions of years.<\/p>\n
Natural cenotes \u2014 sinkholes formed by the collapse of cave ceilings \u2014 punctuate the surface.<\/p>\n
Subterranean cave systems extend in darkness beneath the visible world.<\/p>\n
The ancient Maya recognized the cosmological significance of these underground spaces.<\/p>\n
The underworld, in Maya religious thought, was a real domain \u2014 not a metaphor or a distant concept but a place, accessed through water and through the earth, where supernatural forces operated and where the dead went after life.<\/p>\n
The Sacred Cenote at Chich\u00e9n Itz\u00e1 is the most famous of the site’s natural wells.<\/p>\n
<\/p>\n
A large, roughly circular sinkhole of considerable depth, it served for centuries as a site of ritual activity.<\/p>\n
Objects of extraordinary variety and value \u2014 jade, gold, worked bone, ceramics, rubber, wood, copal incense, and more \u2014 were deposited into it.<\/p>\n
Human remains have been recovered from the cenote as well, though the demographic picture of those remains is different from what the chult\u00fan analysis has revealed.<\/p>\n
The cenote and the chult\u00fan, while physically near each other, preserve distinct patterns of activity.<\/p>\n
The chult\u00fan that is the subject of the 2024 study is described as having been repurposed \u2014 that is, it was not originally constructed as a burial facility.<\/p>\n
<\/p>\n
Chult\u00fans served various practical functions, including storage of water or food, and the subterranean chambers that dot the Maya archaeological landscape were built and used for multiple purposes across different periods.<\/p>\n
This particular feature appears to have been converted, at some point, into a space for the interment of the children whose remains have been studied.<\/p>\n
The broader assemblage from the chult\u00fan is estimated to include approximately 106 individuals, based on the skeletal material that has been recovered.<\/p>\n
Not all of those individuals were accessible to genomic analysis.<\/p>\n
Researchers sampled remains from 64 of them, and from all 64, ancient DNA was successfully recovered \u2014 a high success rate that speaks both to the quality of the skeletal preservation and to the sophisticated methods applied to the samples.<\/p>\n
The Science of Reading Ancient Bone<\/p>\n
<\/p>\n
The recovery of ancient DNA from archaeological remains is not guaranteed.<\/p>\n
DNA degrades over time, affected by temperature, humidity, microbial activity, and the chemistry of the burial environment.<\/p>\n
Tropical and subtropical climates are particularly harsh for DNA preservation \u2014 the warm, often humid conditions of southern Mexico and the Yucat\u00e1n create conditions that tend to accelerate molecular degradation.<\/p>\n
The fact that any usable ancient DNA was recovered from remains in this region at all reflects both specific preservation conditions within the chult\u00fan and the sensitivity of modern extraction methods.<\/p>\n
The primary source for ancient DNA in this study, as in much current ancient genomics work, was the petrous bone \u2014 specifically the left petrous bone of each individual.<\/p>\n
<\/p>\n
The petrous bone is part of the temporal bone of the skull, a dense, extremely hard piece of bone that houses the inner ear.<\/p>\n
Because of its density and its specific internal structure, the petrous bone tends to preserve ancient DNA better than other skeletal elements, even when the surrounding bones have degraded to the point of yielding little or no recoverable genetic material.<\/p>\n
The decision to sample specifically the left petrous bone was a methodological choice designed to reduce the risk of sampling the same individual twice.<\/p>\n
If remains from approximately 106 individuals were mixed or commingled in the chult\u00fan \u2014 if the bones from multiple people were intermingled in ways that made it difficult to tell which bone came from which person \u2014 then sampling randomly might risk taking two samples from the same individual and counting them as two separate people.<\/p>\n
<\/p>\n
By restricting sampling to the left petrous bone, the researchers created a rule: only one sample per individual, since any given person has only one left petrous bone.<\/p>\n
From the 64 successfully analyzed samples, genome-wide data was generated \u2014 meaning that researchers had enough genetic information from across the genome to conduct a range of analyses beyond simply identifying whether the DNA was human.<\/p>\n
They could determine biological sex, examine patterns of genetic ancestry, calculate coefficients of relatedness between individuals, assess dietary isotopes in conjunction with other lines of evidence, and compare the ancient genetic data to modern reference populations.<\/p>\n
The sex determination from genomic data works through the sex chromosomes.<\/p>\n
<\/p>\n
Genetically, individuals with two X chromosomes develop as females; individuals with one X and one Y chromosome develop as males.<\/p>\n
In ancient DNA work, the ratio of reads mapping to the X chromosome versus the Y chromosome can distinguish between these two patterns, even from fragmented, degraded genetic material.<\/p>\n
The signal is unambiguous when sufficient data exists \u2014 and in this study, the signal was unambiguous for all 64 individuals.<\/p>\n
All 64 were genetically male.<\/p>\n
Why That Finding Matters<\/p>\n
The result that all 64 analyzed children were genetically male is significant in part because of what it tells us directly, and in part because of what it suggests about the ritual context in which these children were interred.<\/p>\n
Prior to genomic analysis, the sex of juvenile skeletal remains from Mesoamerican archaeological contexts has often been assigned through osteological assessment \u2014 the visual and metric examination of bones for features associated with biological sex.<\/p>\n
<\/p>\n
But as noted above, these features are unreliable in young children.<\/p>\n
The markers that allow reliable sex estimation in adult skeletons \u2014 the shape of the pelvic inlet and outlet, the greater sciatic notch, the mastoid process, the supraorbital ridge \u2014 are either absent or far less pronounced in juvenile individuals.<\/p>\n
Studies of osteological sex estimation in children have found significant error rates, particularly for younger age groups.<\/p>\n
This means that earlier assessments of the sex distribution of the chult\u00fan remains, based on skeletal morphology, may have been incorrect or at least uncertain.<\/p>\n
Ancient DNA provided an independent, objective, and highly reliable method for establishing biological sex \u2014 one that did not depend on the difficult judgment calls that juvenile osteology requires.<\/p>\n
<\/p>\n
The finding that all 64 analyzed children were male suggests that the individuals deposited in this chult\u00fan were selected, at least in part, on the basis of sex.<\/p>\n
This is not guaranteed by the evidence \u2014 in any sample, it is possible to draw all-male results by chance, particularly if the sample size is not extremely large.<\/p>\n
But the probability of drawing 64 male individuals from a genuinely sex-balanced population is vanishingly small.<\/p>\n
The result is consistent with deliberate selection.<\/p>\n
If the children were selected for being male, this raises questions about what that selection criteria meant within the specific ritual context of Chich\u00e9n Itz\u00e1.<\/p>\n
The Sacred Cenote, Chich\u00e9n Itz\u00e1’s most famous location of ritual deposition, has produced human remains with a different demographic profile \u2014 adults and children, males and females \u2014 suggesting that different ritual contexts at the same site operated with different selection criteria.<\/p>\n
<\/p>\n
The chult\u00fan appears to represent a distinct ritual practice, one in which male children were specifically chosen.<\/p>\n
Why male children specifically?<\/p>\n
This question is one that the genetic evidence raises without resolving.<\/p>\n
The Popol Vuh, the K’iche’ Maya creation narrative that was written down in the sixteenth century and that incorporates older cosmological traditions, features the Hero Twins \u2014 Hunahpu and Xbalanque \u2014 as central characters.<\/p>\n
The Hero Twins are male.<\/p>\n
They descend into the underworld, Xibalba, and ultimately triumph over its lords through a series of cleverness, death, and resurrection.<\/p>\n
The narrative structure of the Hero Twin story is one of the most studied elements of Maya mythology.<\/p>\n
<\/p>\n
The researchers who published the 2024 study noted the relevance of the Hero Twin tradition to their findings \u2014 the maleness of the children, the presence of identical twins, the subterranean location.<\/p>\n
These connections are meaningful as cultural context, as a framework through which the archaeological evidence might be understood.<\/p>\n
What they are not is proof of motive.<\/p>\n
The specific ritual purpose of this specific chult\u00fan was not directly recorded in any surviving text.<\/p>\n
The connection between the Hero Twin mythology and the children interred in the chult\u00fan is interpretive, not established as fact by the genetic data.<\/p>\n
This distinction \u2014 between context and proof, between mythology as cultural background and mythology as demonstrated motive \u2014 is important to maintain.<\/p>\n
<\/p>\n
The Hero Twin connection enriches the interpretation of the evidence.<\/p>\n
It does not establish what happened or why.<\/p>\n
The Kinship Findings<\/p>\n
The genetic analysis of the 64 children went beyond sex determination to examine the biological relationships among the individuals.<\/p>\n
This kind of analysis \u2014 kinship or relatedness analysis \u2014 works by comparing the genomes of different individuals and calculating how many genetic variants they share, and in what patterns.<\/p>\n
Different degrees of biological relationship produce different statistical signatures in the shared genetic data.<\/p>\n
First-degree relatives \u2014 parents and children, or full siblings \u2014 share approximately half of their genetic material through inheritance.<\/p>\n
<\/p>\n
Second-degree relatives \u2014 grandparents and grandchildren, half-siblings, aunts and uncles with their nieces and nephews \u2014 share approximately a quarter.<\/p>\n
Third-degree relatives share approximately one-eighth.<\/p>\n
The further the relationship, the less genetic material is shared and the more difficult it becomes to distinguish genuine relatedness from chance genetic similarity in a population with limited diversity.<\/p>\n
From the 64 analyzed children at the chult\u00fan, researchers identified 11 pairs of close relatives \u2014 either first-degree or second-degree relatives \u2014 based on the genetic data.<\/p>\n
This means that among the 64 individuals, some were found to be siblings, or half-siblings, or related in other first- or second-degree ways.<\/p>\n
<\/p>\n
In total, 16 of the 64 analyzed children \u2014 25 percent of the sample \u2014 had at least one close relative in the analyzed assemblage.<\/p>\n
Think about what that percentage means.<\/p>\n
In a general population, the probability that any randomly selected individual will have a close relative in a specific group of 64 is determined by the size and structure of the population from which the sample is drawn.<\/p>\n
In a population of thousands, finding that one in four of a randomly selected group of 64 individuals shares a close relative with someone else in that same group would be extraordinary.<\/p>\n
Even accounting for the smaller, more interconnected population of a city like Chich\u00e9n Itz\u00e1 at its peak, the 25 percent close-relative figure suggests that the selection of individuals for this chult\u00fan was not random with respect to kinship.<\/p>\n
<\/p>\n
The evidence suggests that children who were related to one another \u2014 who shared parents or grandparents or other close biological relationships \u2014 were deposited in the chult\u00fan together, or at least that related children were included among those deposited over the centuries of the feature’s use.<\/p>\n
Whether this was deliberate selection \u2014 whether families contributed multiple children, whether relatives were chosen together \u2014 or whether it reflects the specific social structure of the families from which sacrificial children were drawn, cannot be determined from the genetic evidence alone.<\/p>\n
And then there were the twins.<\/p>\n
Two Pairs of Identical Twins<\/p>\n
Among the 11 close-relative pairings identified in the study, two were identified as pairs of monozygotic twins \u2014 identical twins, arising from the division of a single fertilized egg rather than from two separate eggs fertilized at the same time.<\/p>\n
Identical twins, or monozygotic twins, share essentially all of their genetic material.<\/p>\n
<\/p>\n
They arise from a single zygote that divides early in development, producing two genetically identical \u2014 or nearly identical \u2014 embryos.<\/p>\n
The genetic signatures of monozygotic twins in ancient DNA analysis are distinguishable from those of fraternal twins or other close relatives: the coefficient of relatedness approaches one, rather than the approximately 0.5 expected for first-degree relatives like full siblings.<\/p>\n
The baseline rate of monozygotic twinning in human populations is roughly 3 to 4 per 1,000 births, largely consistent across populations and largely independent of environmental factors.<\/p>\n
This is in contrast to dizygotic (fraternal) twinning, which varies significantly between populations and is influenced by factors including maternal age and genetics.<\/p>\n
<\/p>\n
The consistency of monozygotic twin rates means that finding two pairs of identical twins among 64 individuals from any single context is statistically remarkable.<\/p>\n
The two pairs of identical twins in the chult\u00fan at Chich\u00e9n Itz\u00e1 join the very small number of ancient identical twin pairs that have been identified in the archaeological record through genomic analysis.<\/p>\n
The methodology for identifying ancient twins from DNA is relatively new, and the Chich\u00e9n Itz\u00e1 findings represent an unusually clear case: two pairs, from a single well-defined archaeological context, analyzed in a single study.<\/p>\n
The presence of two pairs of identical twins in a subterranean ritual burial at Chich\u00e9n Itz\u00e1 cannot be coincidence in any straightforward sense.<\/p>\n
<\/p>\n
In a random sample of 64 people from a general population, the expected number of identical twin pairs present in the same group would be close to zero.<\/p>\n
The presence of two pairs \u2014 representing four of the 64 individuals \u2014 indicates something about how the individuals in this chult\u00fan were selected.<\/p>\n
Were twins specifically chosen for ritual deposition because of their identity as twins?<\/p>\n
The Maya world, at Chich\u00e9n Itz\u00e1 and more broadly, was one in which the concept of twinhood carried specific cosmological weight.<\/p>\n
The Hero Twins of the Popol Vuh are perhaps the most famous expression of this, but twin symbolism appears in Maya art and epigraphy in other contexts as well.<\/p>\n
In a society that invested deep meaning in twinhood \u2014 that understood twins as a specific kind of person, with specific relationships to the supernatural world \u2014 the selection of twins for a ritual context that may have been linked to underworld symbolism would not be surprising.<\/p>\n
<\/p>\n
It would be inappropriate to state, as a fact established by the genetic evidence, that these specific pairs of twins were selected because they represented the Hero Twins.<\/p>\n
That connection is interpretive.<\/p>\n
What the genetic evidence establishes is that two pairs of identical twins were present in this specific ritual context.<\/p>\n
The cultural significance of that presence, within the symbolic world of Classic and Terminal Classic Maya civilization, is for historians, epigraphers, and religious scholars to illuminate alongside the genomic data.<\/p>\n
The Isotope Evidence and Diet<\/p>\n
The study combined genomic analysis with stable isotope analysis of the skeletal remains \u2014 a different chemical technique that addresses different questions.<\/p>\n
Stable isotope analysis of bone collagen and dental enamel can provide information about the diet an individual consumed during life, and about the geographic environment in which they grew up.<\/p>\n
<\/p>\n
The isotope findings added another dimension to the picture of relatedness among the 64 children.<\/p>\n
Related children \u2014 those identified as close relatives through genomic analysis \u2014 also tended to show similar stable isotope profiles, suggesting that they consumed similar diets during their lives.<\/p>\n
This is not surprising, because children raised in the same household by the same parents would typically eat from the same food sources and drink from the same water supplies.<\/p>\n
The dietary similarity among relatives is consistent with the genetic relatedness findings and adds a separate line of evidence suggesting that these children came from the same social and household environments.<\/p>\n
The specific dietary patterns revealed by the isotope data \u2014 what foods were consumed, what proportion of the diet came from marine versus terrestrial sources, what specific signature the local water and food sources left in the bones \u2014 provide information about the social backgrounds of the children.<\/p>\n
<\/p>\n
Were they from elite or high-status families?<\/p>\n
Were they drawn from specific geographic locations?<\/p>\n
The isotope data, in combination with the genetic data, begins to sketch a picture of where these children may have come from and how they lived before they came to be interred in the chult\u00fan.<\/p>\n
Isotope analysis also has the potential, in contexts where sufficient local reference data exists, to identify whether individuals were local to the site or whether they were brought from elsewhere.<\/p>\n
For the Chich\u00e9n Itz\u00e1 chult\u00fan, the local baseline data needed for fine-grained geographic sourcing may be less well-established than for some other archaeological contexts, but the general picture of dietary patterns is informative for understanding the social context of the burial.<\/p>\n
<\/p>\n
A Feature Used Over Centuries<\/p>\n
One of the findings of the study that significantly complicates any simple interpretation of the chult\u00fan is the radiocarbon evidence for when the children were interred there.<\/p>\n
Radiocarbon dating of the skeletal remains from the chult\u00fan shows that the feature was not used in a single mass event.<\/p>\n
The children were not all buried at one time, in one ceremony, in one episode of ritual activity.<\/p>\n
Instead, the radiocarbon dates span centuries, indicating that the chult\u00fan was used as a site of ritual interment repeatedly over a long period of Chich\u00e9n Itz\u00e1’s occupation.<\/p>\n
<\/p>\n
This finding has significant implications for interpretation.<\/p>\n
A single mass burial event is a different kind of ritual action than the repeated, sustained use of a specific location over generations.<\/p>\n
Both can be meaningful within a religious system, but they imply different things about the social organization of the ritual, the physical management of the space, and the way the practice was understood and transmitted within the community over time.<\/p>\n
The centuries-long use of the chult\u00fan suggests that it was recognized and maintained as a sacred or ritually significant space across multiple generations of Chich\u00e9n Itz\u00e1’s population.<\/p>\n
<\/p>\n
The space was not sealed after a single use and forgotten \u2014 it was returned to, opened, and used again, likely across the spans of individual human lifetimes and across the generational transitions of the city’s political and religious leadership.<\/p>\n
This long-term, sustained pattern of use is consistent with the understanding of subterranean spaces \u2014 cenotes, caves, chult\u00fans \u2014 as permanently significant places in Maya religious geography.<\/p>\n
The underground was not a temporary destination but a persistent domain, a place that maintained its sacred character across time and whose use could be renewed and repeated as long as the community that recognized it survived.<\/p>\n
The centuries-long use also means that the 11 close-relative pairings found in the genetic data were not all necessarily from the same time or the same family group or the same ritual event.<\/p>\n
<\/p>\n
Two sets of relatives might have been deposited in the same chult\u00fan separated by decades.<\/p>\n
The kinship connections are not necessarily synchronic \u2014 they do not all have to reflect one community’s ritual practice at one moment.<\/p>\n
They might reflect patterns that persisted across multiple generations, in which the selection of related children or of twins for this specific ritual context was a practice that continued across the long history of the feature’s use.<\/p>\n
Caves, Cenotes, and the Underworld<\/p>\n
To understand the significance of the chult\u00fan as a ritual space, it helps to understand how subterranean spaces were understood in Classic Maya cosmology and religious practice more broadly.<\/p>\n
<\/p>\n
The Maya conception of the universe included multiple layers: the celestial realm above, the terrestrial world of the living, and the underworld \u2014 called Xibalba in some traditions \u2014 below.<\/p>\n
These layers were not sharply separated but were connected through specific kinds of spaces that served as thresholds or portals.<\/p>\n
Water, particularly the still, dark water of cenotes and caves, was understood as the boundary between the world of the living and the world of the dead and supernatural.<\/p>\n
Entry into water was, in a cosmological sense, entry into another domain.<\/p>\n
Cenotes \u2014 the natural sinkholes of the Yucat\u00e1n \u2014 were thus understood as entrances to the underworld, as places where the human world and the supernatural world were in direct contact.<\/p>\n
<\/p>\n
The practice of depositing objects and, in some contexts, individuals into cenotes \u2014 the practice most dramatically exemplified at the Sacred Cenote of Chich\u00e9n Itz\u00e1 \u2014 can be understood within this framework as a form of offering or communication with the underworld, with the supernatural forces that inhabited it, or with the ancestors who had passed into it.<\/p>\n
Caves carried similar significance.<\/p>\n
Many of the surviving Maya religious sites include natural caves or cave systems that were used for ritual activity, often involving water in the cave interior or at its entrance.<\/p>\n
The darkness of the underground, the cool and damp air, the sounds of dripping water and the echoes of enclosed space: these qualities made caves distinctive sensory environments that marked them as different from the surface world, as places where the normal conditions of ordinary life did not apply.<\/p>\n
Chult\u00fans \u2014 the artificial underground chambers that the Maya carved into the limestone bedrock \u2014 shared something of this symbolic geography.<\/p>\n
<\/p>\n
An artificial underground space participates in the broader symbolic category of the subterranean, the below, the underworld.<\/p>\n
The specific construction of a chult\u00fan by human hands does not necessarily separate it from the cosmological significance of natural caves and cenotes; it may extend that significance into a deliberate architectural form, a human-made version of the naturally sacred underground space.<\/p>\n
The repurposed chult\u00fan near the Sacred Cenote at Chich\u00e9n Itz\u00e1 thus sits within a dense web of symbolic associations.<\/p>\n
It is underground.<\/p>\n
<\/p>\n
It is near water and the cenote.<\/p>\n
It contains the remains of children who, in the context of the broader ritual practices of Chich\u00e9n Itz\u00e1, may have been understood as offerings or participants in ceremonies that had cosmological dimensions.<\/p>\n
The specific meaning of those ceremonies, and the exact nature of the children’s role in them, is not directly recoverable from the genetic or archaeological evidence.<\/p>\n
The Popol Vuh and the Hero Twins<\/p>\n
The Popol Vuh is one of the most important surviving literary texts from the pre-Columbian Americas.<\/p>\n
<\/p>\n
Written down in the K’iche’ Maya language using the Latin alphabet in the sixteenth century, it records a complex creation narrative that incorporates earlier oral and possibly written traditions.<\/p>\n
The text describes the creation of the world, the deeds of supernatural beings, the descent of the Hero Twins into the underworld, and the eventual creation of human beings.<\/p>\n
The Hero Twins \u2014 Hunahpu and Xbalanque \u2014 are at the center of one of the narrative’s most extended sequences.<\/p>\n
They are the sons of a supernatural figure whose head is preserved in a gourd tree and who impregnates a woman in the underworld through the action of spitting on her hand.<\/p>\n
Born of this unusual parentage, the twins grow up to be ballplayers \u2014 a significant detail, given the importance of the ball game in Maya culture \u2014 and are eventually summoned to the underworld by its lords, who have been disturbed by the noise of the twins’ play.<\/p>\n
<\/p>\n
In the underworld, the twins are subjected to a series of tests in various houses of suffering.<\/p>\n
They survive through cleverness and magical ability.<\/p>\n
Eventually they are killed, but they are reborn \u2014 first as fish, then as wandering performers who dance and display miraculous powers.<\/p>\n
Ultimately they defeat the lords of the underworld and ascend to become the sun and the moon, establishing the current cosmic order.<\/p>\n
The narrative is rich with themes that resonate with the archaeological evidence from the chult\u00fan: twinhood, descent into the underworld, death and rebirth, the relationship between the surface world and the supernatural domain below.<\/p>\n
These themes were not limited to the Popol Vuh’s specific K’iche’ tradition; similar motifs appear across Maya art and epigraphy from multiple periods and regions, suggesting that they were broadly shared elements of Maya religious thought.<\/p>\n
<\/p>\n
The researchers who published the 2024 study noted these connections explicitly: the maleness of all 64 analyzed children, the presence of two pairs of identical twins, the subterranean location with its underworld associations, and the overall ritual context.<\/p>\n
The Hero Twin narrative provides a framework within which these specific features of the burial make cultural sense.<\/p>\n
What it does not provide is proof.<\/p>\n
The Popol Vuh was written down in the sixteenth century, centuries after the main period of use of the chult\u00fan at Chich\u00e9n Itz\u00e1.<\/p>\n
The K’iche’ Maya tradition it represents is related to but not identical with the traditions of the Terminal Classic and earlier Maya of the northern lowlands.<\/p>\n
Drawing a direct line from the Popol Vuh narrative to the specific ritual actions at Chich\u00e9n Itz\u00e1 requires assumptions about cultural continuity and geographical unity that archaeologists and epigraphers approach with appropriate caution.<\/p>\n
<\/p>\n
The Hero Twin tradition is part of the interpretive context for the chult\u00fan findings.<\/p>\n
It is not an established explanation.<\/p>\n
The Ritual Interpretation and Its Limits<\/p>\n
The 2024 study interprets the interments in the chult\u00fan as occurring within a ritual-sacrifice context.<\/p>\n
This interpretation is supported by the overall character of the evidence: the deliberate nature of the feature’s use, the demographic profile of the individuals, the lack of typical domestic mortuary context, and the broader evidence of ritual activity at and around the Sacred Cenote.<\/p>\n
What ancient DNA cannot establish is the specific nature of the ritual actions that accompanied the children’s deaths or interment.<\/p>\n
<\/p>\n
The study does not claim to have identified the cause of death for any of the individuals.<\/p>\n
Ancient skeletal remains from tropical burial environments often preserve poorly enough that specific skeletal trauma that might indicate sacrifice is not identifiable, and the genetics themselves do not carry information about how someone died.<\/p>\n
The ritual-sacrifice interpretation is contextual and interpretive, not directly established by the genomic data.<\/p>\n
The genomic data establishes who was there, how they were related, what their sex was, and something about their diet and ancestry.<\/p>\n
What happened to them and why is a question that must be addressed through the combination of archaeological context, comparative evidence from other Maya sites and periods, analysis of epigraphy and art, and the broader scholarly understanding of Maya religious practice.<\/p>\n
<\/p>\n
This distinction between what the genetics shows and what remains interpretive is not a limitation of the study \u2014 it is honest science.<\/p>\n
The study’s authors were clear about what the genetic data established and appropriately cautious about the interpretive frameworks through which those findings were contextualized.<\/p>\n
The ritual interpretation also must be placed within a broader understanding of Maya society that resists reduction to a single dimension.<\/p>\n
Chich\u00e9n Itz\u00e1 was a city with a complex economy, sophisticated political organization, extensive trade connections, impressive achievements in architecture, astronomy, and written communication, and a rich and layered religious culture.<\/p>\n
The ritual practices that may have included the sacrifice of children were part of this complex society, not the defining feature of it.<\/p>\n
<\/p>\n
Presenting Maya civilization primarily through the lens of sacrifice distorts a far richer historical reality.<\/p>\n
Living Maya communities today are the descendants of the same civilization that built Chich\u00e9n Itz\u00e1, and they maintain diverse cultural, linguistic, and spiritual traditions that continue into the present.<\/p>\n
The ancient individuals in the chult\u00fan are their ancestors, not the spectacle of a foreign culture.<\/p>\n
The Genetic Continuity Finding<\/p>\n
Alongside the specific findings about the children in the chult\u00fan, the 2024 study investigated a broader question about the population genetics of ancient and modern Maya people from the region.<\/p>\n
The ancient genome data from the Chich\u00e9n Itz\u00e1 chult\u00fan was compared to genetic data from present-day Maya individuals, specifically from a community called Tixcacaltuyub, located in Yucat\u00e1n, Mexico.<\/p>\n
<\/p>\n
The comparison found evidence of substantial genetic continuity between the ancient individuals at Chich\u00e9n Itz\u00e1 and the modern Maya people from this community.<\/p>\n
The genetic ancestry of the ancient children was closely related to the genetic ancestry of living Maya people in the region.<\/p>\n
This finding may seem intuitive \u2014 of course the ancient Maya are the ancestors of the modern Maya \u2014 but it carries specific scientific significance in the context of the post-contact demographic history of the Maya people.<\/p>\n
The arrival of Europeans in Mesoamerica beginning in the early sixteenth century brought with it diseases to which Indigenous populations had no prior exposure.<\/p>\n
Smallpox, measles, typhus, and other epidemic diseases swept through the Americas with catastrophic effect.<\/p>\n
<\/p>\n
Population collapse was severe across many parts of the Maya world, as in other regions of the Americas.<\/p>\n
Some estimates suggest that the Indigenous population of Mesoamerica declined by 80 percent or more in the century following contact, due to a combination of disease, violence, and social disruption.<\/p>\n
This demographic catastrophe has raised questions in population genetics research about whether the modern descendants of ancient Mesoamerican populations represent genuine genetic continuity with those ancient populations, or whether the severity of the population collapse introduced major shifts in the genetic composition of the surviving communities.<\/p>\n
In simple terms: after losing the vast majority of a population to epidemic disease, do the survivors genetically represent the pre-contact population, or does the bottleneck effect of catastrophic population decline change the genetic profile in significant ways?<\/p>\n
<\/p>\n
The 2024 study’s finding of genetic continuity between the ancient Chich\u00e9n Itz\u00e1 individuals and modern Maya from Tixcacaltuyub provides evidence that, at least in this comparison, the population genetic continuity across the contact period was substantial.<\/p>\n
The modern Maya from this region appear to be genuine descendants \u2014 in a genetic as well as a historical and cultural sense \u2014 of the ancient people who lived at and around Chich\u00e9n Itz\u00e1.<\/p>\n
This is an important and meaningful finding, not merely as an abstract genetic result but as a statement about the historical experience of Maya people.<\/p>\n
Despite the devastation of the colonial period, despite the population collapse and the centuries of political and cultural disruption, the Maya communities of the Yucat\u00e1n Peninsula maintained genetic connections to their pre-contact ancestors.<\/p>\n
The people are still there, carrying in their genomes the legacy of thousands of years of continuous presence in this landscape.<\/p>\n
<\/p>\n
The Immune Gene Findings<\/p>\n
The 2024 study also examined the ancient genomes for evidence of genetic changes in immune-related genes across the contact period \u2014 specifically, between the ancient individuals from the pre-contact Chich\u00e9n Itz\u00e1 era and modern Maya individuals.<\/p>\n
The rationale for this analysis connects to the epidemic history of the Americas after European contact.<\/p>\n
Epidemic diseases exert strong selective pressure on human populations.<\/p>\n
Individuals who happen to carry genetic variants that provide some protection against specific pathogens survive at higher rates than those who do not.<\/p>\n
<\/p>\n
Over generations, this selection pressure can shift the frequency of immune-related genetic variants in a population \u2014 increasing the frequency of variants that were associated with survival and decreasing the frequency of variants that were not.<\/p>\n
If the post-contact epidemics exerted this kind of selective pressure on the Maya population, we might expect to see differences in the frequencies of specific immune-related genetic variants between the pre-contact ancient individuals (who were never exposed to European diseases) and the modern individuals (whose ancestors survived the epidemic period).<\/p>\n
The 2024 study investigated this prediction and found evidence consistent with it: certain immune-related genetic variants showed patterns of frequency change between the ancient and modern samples that are consistent with selection during the epidemic period.<\/p>\n
This finding adds a biological dimension to the historical record of the catastrophic post-contact epidemics.<\/p>\n
<\/p>\n
The demographic devastation was so severe, and the selective pressure so intense, that it left a detectable genetic signature in the immune systems of the surviving population’s descendants.<\/p>\n
The modern Maya people of Tixcacaltuyub carry, in their immune gene frequencies, the trace of what their ancestors survived in the sixteenth and seventeenth centuries.<\/p>\n
This genomic evidence does not tell us anything that historical sources did not already establish about the severity of the post-contact epidemics.<\/p>\n
But it provides independent, biological corroboration of that history, and it adds specificity about which aspects of the immune system were most affected by the selective pressure of specific diseases.<\/p>\n
For the people whose history is being investigated, this finding is not abstract.<\/p>\n
<\/p>\n
It is part of the story of survival \u2014 of how a population that lost the vast majority of its members to catastrophic disease continued, rebuilt, and maintained the cultural and genetic heritage of a civilization that has persisted for millennia.<\/p>\n
Community Engagement in the Research<\/p>\n
The 2024 Nature study acknowledged the importance of community engagement in the research process.<\/p>\n
The investigation of human remains, particularly those from Indigenous contexts, raises specific ethical questions about whose knowledge and whose consent matter in the research process.<\/p>\n
Archaeological research has a complicated history in this regard: the history of Indigenous human remains being removed from their communities, studied by outside researchers without community knowledge or consent, and housed in institutions far from their origin is a documented and ongoing concern in North American and Mesoamerican archaeology.<\/p>\n
The research team noted their engagement with relevant Maya communities and stakeholders as part of the research process.<\/p>\n
<\/p>\n
The specifics of that engagement \u2014 what consultations took place, with which communities, and how community input shaped the research design or the interpretation of findings \u2014 are not detailed extensively in the published study, but the acknowledgment of community relationships in the research is significant.<\/p>\n
The legal and regulatory context for archaeological research in Mexico \u2014 where Chich\u00e9n Itz\u00e1 is located, and where the remains and their associated materials are held \u2014 involves the Instituto Nacional de Antropolog\u00eda e Historia (INAH), the federal institution responsible for the management and protection of Mexico’s archaeological heritage.<\/p>\n
Research on skeletal remains from Mexican archaeological sites proceeds within the framework of Mexican heritage law and INAH’s regulations.<\/p>\n
The ethical landscape for ancient genomics research on Indigenous human remains has evolved considerably in recent years, influenced by both the growing sophistication of the science and the increasing assertiveness of Indigenous communities in demanding meaningful participation in decisions about their ancestors’ remains.<\/p>\n
<\/p>\n
The Chich\u00e9n Itz\u00e1 study is one of many recent ancient genomics publications that have had to navigate this landscape, and the acknowledgment of community engagement in the published study reflects awareness of those ethical dimensions.<\/p>\n
The living Maya communities of the Yucat\u00e1n Peninsula are not passive recipients of research conducted about their ancestors.<\/p>\n
They are active communities with their own relationships to their history, their own interpretive frameworks for understanding ancient Maya civilization, and their own interests in how that civilization is represented in scholarship and in public discourse.<\/p>\n
Research that engages with those communities as partners rather than simply as subject matter is more ethically sound and, arguably, more intellectually complete.<\/p>\n
What Traditional Archaeology Could Not Have Revealed<\/p>\n
<\/p>\n
The power of the 2024 study lies partly in what it demonstrates about the limits of traditional archaeological methods and the capabilities that ancient genomics adds to the investigative toolkit.<\/p>\n
Traditional archaeological analysis of the chult\u00fan remains would have yielded significant information.<\/p>\n
The skeletal material itself \u2014 the bones and teeth of the children \u2014 can reveal information about age at death, about growth and development, about the presence of pathological conditions that affected the skeleton, and about some aspects of diet and geographic origin through stable isotope analysis.<\/p>\n
Radiocarbon dating of the skeletal material provides chronological information about when the individuals died.<\/p>\n
The archaeological context \u2014 the feature itself, its relationship to other features at the site, the associated artifacts if any \u2014 provides information about the spatial and architectural setting of the interments.<\/p>\n
<\/p>\n
What traditional archaeology could not have revealed with confidence:<\/p>\n
The biological sex of the individuals.<\/p>\n
As noted above, skeletal sex estimation in young children is unreliable.<\/p>\n
Without genomic analysis, the sex of the 64 analyzed children would have remained uncertain or would have been subject to potentially incorrect assignment based on unreliable skeletal markers.<\/p>\n
The biological relationships among the individuals.<\/p>\n
Osteological analysis can sometimes identify shared skeletal features that suggest biological relatedness \u2014 shared trait frequencies, unusual anatomical variants that appear in multiple individuals \u2014 but this is an inexact and indirect approach that cannot produce the quantitative relatedness coefficients that genomic analysis provides.<\/p>\n
The identification of 11 close-relative pairs, including two pairs of identical twins, was simply not possible without ancient DNA.<\/p>\n
<\/p>\n
The genetic ancestry of the individuals, and its relationship to modern populations.<\/p>\n
Understanding the population genetic context of the ancient children \u2014 their relationship to other ancient and modern Maya individuals \u2014 requires genomic data that cannot be derived from skeletal morphology.<\/p>\n
The evidence for immune-related genetic changes across the contact period.<\/p>\n
This question requires comparative genomic data from ancient and modern individuals and cannot be addressed through traditional archaeological analysis at all.<\/p>\n
The specific information about monozygotic twinhood.<\/p>\n
Two people can be identical twins and leave no trace of that twinhood in the skeleton.<\/p>\n
<\/p>\n
Their bones, analyzed separately, would appear as two ordinary individuals.<\/p>\n
Only genomic comparison can establish the near-identical genetic profiles that identify monozygotic twins.<\/p>\n
Without ancient DNA, the two pairs of identical twins in the chult\u00fan would have remained forever unknown as twins.<\/p>\n
The transformation that ancient genomics brings to archaeological interpretation is not the replacement of traditional methods but their extension.<\/p>\n
The skeletal analysis, the stable isotope work, the radiocarbon dating, the spatial analysis of the burial feature, the broader archaeological interpretation of Chich\u00e9n Itz\u00e1’s history: all of these remain essential and complementary.<\/p>\n
Ancient genomics adds new dimensions of information that enrich and sometimes transform the interpretation of evidence that traditional methods have already established.<\/p>\n
<\/p>\n
The Broader Maya Genomic Picture<\/p>\n
The 2024 study of the Chich\u00e9n Itz\u00e1 chult\u00fan is one contribution to a growing body of ancient Maya genomic research that is building a more detailed picture of population history, movement, and change across the Maya world over millennia.<\/p>\n
Ancient genomic research in Mesoamerica is a younger field than comparable work in Europe or East Asia, partly because the preservation conditions in tropical and subtropical environments are challenging for ancient DNA, and partly because the ethical and regulatory context for research on Indigenous human remains has required more extensive community engagement and has sometimes limited the speed of sample acquisition and analysis.<\/p>\n
The development of more sensitive extraction methods and the increasing willingness of research teams to invest in the necessary community consultation have accelerated the pace of research in recent years.<\/p>\n
<\/p>\n
Studies of ancient Maya genomes from multiple sites and time periods have revealed evidence of significant population diversity within the Maya world, both geographically and chronologically.<\/p>\n
Different Maya communities at different times showed distinct genetic profiles that reflect local population histories, migration events, and degrees of connectivity with other populations.<\/p>\n
The Maya world was not genetically uniform, and the peoples who built different Maya cities were not all identical in their genetic background.<\/p>\n
At the same time, studies have found evidence for long-term continuity in some regions \u2014 genetic connections between ancient populations and their modern descendants that persist across thousands of years of occupation in the same landscape.<\/p>\n
The Chich\u00e9n Itz\u00e1 study’s finding of continuity between the ancient chult\u00fan individuals and modern Maya from Tixcacaltuyub fits within this broader pattern of regional genetic continuity in some parts of the Maya world.<\/p>\n
<\/p>\n
Studies have also examined the genetic impact of the post-contact demographic catastrophe, investigating whether the severe population declines of the sixteenth and seventeenth centuries produced detectable genetic bottlenecks in the surviving populations.<\/p>\n
The results are complex and vary by region, reflecting the different intensities of epidemic mortality, displacement, and social disruption in different parts of the Maya world.<\/p>\n
The accumulating body of ancient Maya genomic data is also beginning to shed light on questions of long-range population movement and connectivity \u2014 how genetic ancestry flowed between the Maya world and neighboring regions of Mesoamerica, and how ancient migrations and cultural interactions shaped the genetic diversity of Maya populations over time.<\/p>\n
The Specific Rarity of Ancient Twin Identification<\/p>\n
<\/p>\n
The identification of identical twins in ancient archaeological contexts through genomic analysis is rare enough to warrant specific discussion.<\/p>\n
Most ancient genomics research focuses on population-level questions: where did a particular ancient population come from, how is it related to other ancient and modern populations, what genetic changes occurred over time?<\/p>\n
The identification of specific biological relationships between individual ancient people \u2014 kinship analysis at the level of specific pairs of individuals \u2014 is a methodologically distinct enterprise that requires a different kind of analysis and benefits from having multiple individuals from the same archaeological context available for comparison.<\/p>\n
When ancient DNA studies have the opportunity to compare multiple individuals from the same site or burial context, kinship analysis becomes possible.<\/p>\n
<\/p>\n
But the combination of circumstances required to find identical twins in such a context is specific: ancient DNA must be recoverable from both individuals; both must be present in the same assemblage; and the assemblage must be analyzed by researchers conducting kinship analysis rather than focusing exclusively on population-level questions.<\/p>\n
Prior to the Chich\u00e9n Itz\u00e1 study, ancient identical twins had been identified in a small number of other archaeological contexts using genomic methods.<\/p>\n
Each case has attracted significant attention precisely because of the rarity of the finding and the specific human story it illuminates.<\/p>\n
The Chich\u00e9n Itz\u00e1 case is distinctive for finding not one but two pairs of identical twins in the same specific archaeological context.<\/p>\n
The probability calculation for this is illustrative even if approximate.<\/p>\n
<\/p>\n
If monozygotic twins occur at roughly 3 to 4 per 1,000 births, and if in a group of 64 individuals we find not just one pair but two pairs \u2014 meaning that 4 of the 64 are members of monozygotic twin pairs \u2014 the departure from chance expectation is striking.<\/p>\n
In a randomly assembled group of 64 individuals drawn from a large population, the probability of finding even one pair of identical twins present together is low; the probability of finding two pairs is lower still.<\/p>\n
The two pairs of twins in the Chich\u00e9n Itz\u00e1 chult\u00fan were not there by accident.<\/p>\n
Their presence reflects whatever process of selection determined who was interred in this underground ritual feature over the centuries of its use.<\/p>\n
What Genomics Cannot Resolve<\/p>\n
<\/p>\n
Ancient genomics is a powerful tool, but it is important to be clear about what it cannot tell us.<\/p>\n
It cannot tell us the specific ritual circumstances under which the children died.<\/p>\n
The cause of death for the individuals in the chult\u00fan is not established by the genetic data.<\/p>\n
Whether they were killed by specific ritual methods, whether they died of disease or accident or other causes and were then deposited in the chult\u00fan, or whether the precise circumstances varied across the centuries of the feature’s use: none of these questions is answered by the genome-wide data.<\/p>\n
It cannot tell us what the children or their families understood about the ritual in which they participated.<\/p>\n
<\/p>\n
The subjective experience of the people involved \u2014 their beliefs, their understanding of what was happening, their emotional responses \u2014 is not accessible through any archaeological method.<\/p>\n
We can reconstruct the material dimensions of the past with increasing precision.<\/p>\n
We cannot recover the interior lives of the people who lived it.<\/p>\n
It cannot definitively connect the specific ritual practices at this chult\u00fan to the specific narratives of the Popol Vuh or any other surviving text.<\/p>\n
The connection between the material evidence and the mythological framework is interpretive, made by researchers working across different domains of expertise, and it carries the uncertainties that all cross-domain interpretation carries.<\/p>\n
It cannot establish that the selection of twins, or related children, for this specific ritual context was a conscious and deliberate policy that persisted across the centuries of the chult\u00fan’s use, as opposed to patterns that might have complex and varied explanations across different episodes of use.<\/p>\n
<\/p>\n
What it can do \u2014 and what the 2024 study achieved \u2014 is transform the factual foundation on which all of these interpretive questions rest.<\/p>\n
The sex of the children, the kinship among them, the presence of identical twins, the dietary patterns of related individuals, the genetic continuity with modern Maya communities: these are facts that were established by the genomic analysis with a precision and confidence that traditional methods could not have provided.<\/p>\n
All of the interpretive work that scholars will continue to do about the meaning of the chult\u00fan, about the ritual practices of Chich\u00e9n Itz\u00e1, and about the cosmological significance of these interments now rests on a more solid factual foundation than it did before.<\/p>\n
The Children as People<\/p>\n
<\/p>\n
Amid the genomics and the statistics and the interpretive frameworks, it is worth pausing to remember that the 64 analyzed individuals were children.<\/p>\n
They were young \u2014 described as subadults, meaning they had not yet reached physical maturity at the time of their deaths.<\/p>\n
They grew up in households, were cared for by adults, ate food and drank water and learned the language and customs of the community that raised them.<\/p>\n
Their genetic data shows that some of them were brothers, and that some of them were twins \u2014 pairs who shared not only their genetic makeup but the specific experience of being born together, of growing up as twins in a culture that invested deep meaning in twinhood.<\/p>\n
They had bodies and faces and personalities that are not accessible to any scientific analysis.<\/p>\n
<\/p>\n
They had experiences that the stable isotope data can sketch in broad dietary terms but cannot describe.<\/p>\n
They had relationships with specific people \u2014 parents, siblings, cousins, neighbors \u2014 that the kinship analysis can partially reconstruct in terms of biological relatedness but cannot animate as lived human experience.<\/p>\n
They were not abstractions.<\/p>\n
They were not illustrations of a principle or examples for a textbook.<\/p>\n
They were children who lived in a specific place at a specific time, who were members of specific families and communities, and who came, through circumstances we cannot fully reconstruct, to be interred in an underground chamber near the greatest city of their world.<\/p>\n
The scientific analysis that has been conducted on their remains \u2014 the ancient DNA work, the isotope analysis, the radiocarbon dating \u2014 is valuable and important work that tells us things that would otherwise be unknowable.<\/p>\n
<\/p>\n
It is also work that was done on the physical remains of specific people, and its value does not exempt it from the ethical obligations that attending to the dead requires.<\/p>\n
The living Maya communities of the Yucat\u00e1n and beyond, who are the descendants of the people of Chich\u00e9n Itz\u00e1, have specific relationships to these ancestral remains and to the research conducted on them.<\/p>\n
Their perspectives on that research, and on how it is conducted and communicated, are part of the ethical context in which ancient genomics work must take place.<\/p>\n
The Question of Selection<\/p>\n
<\/p>\n
The single most provocative question that the 2024 findings raise \u2014 more provocative than the twin finding itself, in some ways \u2014 is the question of how these specific children came to be in this specific place.<\/p>\n
The characteristics of the assemblage: all male, a quarter with close relatives in the group, two pairs of identical twins, deposited over centuries in a subterranean feature near the Sacred Cenote.<\/p>\n
These characteristics did not happen by chance.<\/p>\n
They reflect selection \u2014 choices made by the living about who would be interred in this feature.<\/p>\n
Understanding those choices, and the criteria that guided them, is where the greatest remaining uncertainty lies.<\/p>\n
Were twins specifically sought out and selected?<\/p>\n
<\/p>\n
If so, how?<\/p>\n
A society without genomic testing would have to rely on the visible fact of twinhood \u2014 on the actual presence of twins in a community \u2014 to identify them.<\/p>\n
Twins are identifiable in any community: they are the children born together, the siblings who look identical, the unusual pair whose existence carries cosmological significance in a culture that understands twinhood as meaningful.<\/p>\n
If the ritual practice at this chult\u00fan specifically sought twins, twin children would have been known and identifiable in the communities from which sacrificial individuals were drawn.<\/p>\n
<\/p>\n
Were related children sought out specifically?<\/p>\n
The mechanism for this is less clear.<\/p>\n
The genetic relatedness of 25 percent of the assemblage might reflect a practice in which families contributed multiple children to the ritual.<\/p>\n
It might reflect the drawing of ritual participants from a specific social stratum in which the relevant families were closely connected by kinship.<\/p>\n
It might reflect the specific population structure of communities from which participants were drawn, where high degrees of relatedness within small communities meant that randomly selected individuals would frequently share genetic connections.<\/p>\n
The diet similarity among relatives adds another dimension.<\/p>\n
<\/p>\n
Children raised together, in the same household, eating the same food from the same sources, would show similar isotope profiles.<\/p>\n
The fact that related children in the assemblage show similar dietary isotope patterns suggests that at least some of the related pairs were raised in the same household environment \u2014 that they were genuinely members of the same family group rather than distant relatives who happened to share genetic ancestry.<\/p>\n
This raises the possibility that entire sibling groups, or pairs of twins and their close relatives, were selected together \u2014 that the selection was at the level of family units rather than individuals.<\/p>\n
This is a different model of how the ritual functioned than one in which individuals were chosen one at a time without reference to their family connections.<\/p>\n
<\/p>\n
These questions cannot be answered by the genetic data alone.<\/p>\n
They require integration with the historical, epigraphic, and comparative archaeological evidence about how Maya ritual sacrifice functioned \u2014 who was selected, by what criteria, from which communities, and through what social processes.<\/p>\n
The 2024 study has provided a new set of facts that must be explained by any adequate account of the ritual.<\/p>\n
The explanation itself remains to be developed.<\/p>\n
The Living Legacy<\/p>\n
The genetic continuity finding is, in some ways, the most important part of the 2024 study for understanding the full significance of the research.<\/p>\n
<\/p>\n
The ancient individuals in the Chich\u00e9n Itz\u00e1 chult\u00fan are not representatives of a vanished civilization.<\/p>\n
They are ancestors of living people.<\/p>\n
The Maya communities of the Yucat\u00e1n Peninsula \u2014 speaking Maya languages, maintaining cultural practices that draw on ancient traditions, navigating the specific challenges of life in contemporary Mexico and the Maya diaspora beyond \u2014 are the continuation of the same human population that built Chich\u00e9n Itz\u00e1, that deposited children in the underground chamber near the Sacred Cenote, that maintained the ritual and ceremonial life of one of the greatest cities in pre-Columbian Mesoamerica.<\/p>\n
The genetic continuity between the ancient chult\u00fan individuals and the modern Maya of Tixcacaltuyub is not just a scientific finding.<\/p>\n
<\/p>\n
It is a statement about human persistence.<\/p>\n
Despite the catastrophic demographic collapse of the sixteenth and seventeenth centuries, despite the centuries of colonial rule and the suppression of Maya cultural and religious practices, despite the continuing economic and social marginalization of many Maya communities in the present day, the people are still there.<\/p>\n
Their genomes carry the ancestry of the ancient city.<\/p>\n
Their cultural traditions draw, in various ways, on the deep history of Maya civilization.<\/p>\n
Chich\u00e9n Itz\u00e1 attracts more than a million visitors a year.<\/p>\n
<\/p>\n
Most of those visitors are not Maya.<\/p>\n
They come to see the pyramids, to photograph El Castillo, to learn something about the ancient civilization that built this extraordinary urban center.<\/p>\n
The marketing of Chich\u00e9n Itz\u00e1 as a tourist attraction has, at various times and in various ways, presented the Maya world as ancient and therefore somewhat remote \u2014 as a civilization whose greatest days are in the past, whose pyramids are now the property of archaeology and tourism rather than of a living people.<\/p>\n
The genetic continuity finding is a counterweight to that narrative.<\/p>\n
<\/p>\n
The people who built these pyramids are not fully gone.<\/p>\n
Their descendants are alive, and in a biologically meaningful sense, the ancient city belongs to them as much as it belongs to any other interpretation of its significance.<\/p>\n
The Final Accounting: What the DNA Found<\/p>\n
The 2024 Nature study set out to investigate the human remains from a subterranean chult\u00fan near the Sacred Cenote at Chich\u00e9n Itz\u00e1 using ancient genomic methods.<\/p>\n
It succeeded in generating genome-wide data from 64 subadult individuals \u2014 a high success rate for a tropical preservation context \u2014 and the findings transformed the understanding of who those individuals were.<\/p>\n
<\/p>\n
All 64 analyzed individuals were genetically male.<\/p>\n
This was the first finding, and it established that the demographic profile of the chult\u00fan was distinctively and consistently male \u2014 a pattern that traditional skeletal analysis had been unable to establish with confidence because of the difficulty of sex estimation in juvenile remains.<\/p>\n
Among the 64 individuals, 11 close-relative pairings were identified, meaning that 11 pairs of children were found to be first-degree or second-degree biological relatives.<\/p>\n
Overall, 16 of 64 analyzed children \u2014 25 percent \u2014 had at least one close relative in the analyzed assemblage.<\/p>\n
<\/p>\n
Two of the 11 close-relative pairings were identified as pairs of monozygotic twins \u2014 identical twins, who arose from the division of a single fertilized egg and who therefore share essentially all of their genetic material.<\/p>\n
Finding two pairs of identical twins in a single archaeological context, among a group of 64 individuals, is statistically extraordinary.<\/p>\n
The stable isotope analysis found that related children tended to have similar dietary profiles, consistent with their having been raised in the same household environments \u2014 members of the same family groups rather than distant genetic relatives with no shared upbringing.<\/p>\n
Radiocarbon dating showed that the chult\u00fan was used over centuries, not in a single mass event, indicating that the ritual practice it represents was sustained across multiple generations.<\/p>\n
<\/p>\n
The broader genomic analysis found evidence of genetic continuity between the ancient individuals and modern Maya people from the Tixcacaltuyub community in Yucat\u00e1n, confirming that the modern Maya are the genuine biological descendants of the ancient population of the region.<\/p>\n
Examination of immune-related genes found patterns consistent with selection during the post-contact epidemic period, adding a biological dimension to the historical record of the demographic catastrophe that followed European contact.<\/p>\n
And through all of this \u2014 through the statistics and the genomic analysis and the isotope work and the radiocarbon dating \u2014 two pairs of children who were born as identical twins are now known to the world in a way that would not have been possible without ancient DNA.<\/p>\n
They were there, in the underground chamber near the Sacred Cenote, in a city that their families and their community built and inhabited and believed in.<\/p>\n
<\/p>\n
They were twins in a civilization that understood twins as cosmologically meaningful.<\/p>\n
They were children.<\/p>\n
The DNA found them.<\/p>\n
What it cannot find \u2014 what no science can recover \u2014 is their names, their faces, their voices, the specific texture of the lives they lived before they came to rest in the limestone darkness beneath Chich\u00e9n Itz\u00e1.<\/p>\n
The Questions That Remain<\/p>\n
After the study, after the genomics, after the interpretation of the evidence through the lenses of Maya mythology and population genetics and isotope chemistry: what questions remain?<\/p>\n
The most profound remaining question is the one that the genetic data raises most sharply: how were these specific children selected?<\/p>\n
<\/p>\n
The all-male profile, the 25 percent close-relative figure, the presence of two pairs of identical twins \u2014 these are not random outcomes.<\/p>\n
They reflect criteria of selection.<\/p>\n
Understanding those criteria requires understanding the ritual logic of the specific practice this chult\u00fan represents, and that understanding requires historical and epigraphic work that goes beyond genomics.<\/p>\n
The question of whether the selection of related children or of twins was a conscious, explicit criterion for inclusion in this ritual context, or whether it was an emergent consequence of other selection processes, remains open.<\/p>\n
If families were expected to contribute male children to this ritual, and if those families were closely interrelated, the high kinship rate might be a consequence of family structure rather than of deliberate selection for relatedness.<\/p>\n
<\/p>\n
If twins were specifically sought because of their cosmological significance, that is a different kind of deliberate selection.<\/p>\n
The question of what specific ritual practice occurred in the chult\u00fan, and what the participants \u2014 the children themselves, their families, the ritual specialists who may have managed the ceremony \u2014 understood about its meaning, remains beyond the reach of any archaeological method.<\/p>\n
The physical evidence is now substantially better understood, thanks to the 2024 study.<\/p>\n
The human experience of the ritual is irretrievably in the past.<\/p>\n
The question of what the broader pattern of chult\u00fan use at Chich\u00e9n Itz\u00e1 looks like \u2014 whether other features at the site show similar demographic patterns, whether this specific practice was unique to this feature or part of a wider pattern of ritual activity \u2014 requires additional investigation.<\/p>\n
<\/p>\n
And the question of how the living Maya communities relate to this research, what they make of the findings, and how the knowledge generated by the 2024 study contributes to or complicates the ongoing relationship between Maya communities and the archaeological interpretation of their ancestors’ lives: this is a question that will be answered, if at all, in dialogue with those communities rather than by outside researchers working alone.<\/p>\n
A Final Thought<\/p>\n
The subterranean chamber carved from the limestone of the Yucat\u00e1n Peninsula has been empty of its original contents since the excavations that first brought the remains of the children to light.<\/p>\n
The bones are now in institutional storage, subject to the regulations and ethical frameworks that govern the care of Indigenous human remains in Mexico.<\/p>\n
The site itself \u2014 the chult\u00fan, the cenote, the pyramids and plazas of Chich\u00e9n Itz\u00e1 \u2014 continues to exist in the landscape of a peninsula that has been inhabited by Maya people for thousands of years and that continues to be inhabited by their descendants today.<\/p>\n
The ancient DNA that was extracted from the left petrous bones of 64 children has been analyzed, published, and added to the scientific record.<\/p>\n
<\/p>\n
It has told the world things that could not have been known any other way: that all 64 were male, that a quarter of them had close relatives in the same burial, that two pairs of identical twins lay together in that underground space for centuries.<\/p>\n
The twins, whoever they were, arrived in that underground space together.<\/p>\n
Whether they were brought there at the same time, in the same ceremony, or whether they were interred separately across the years while the other’s bones already lay in the darkness: this is not known.<\/p>\n
What is known is that they were there, and that they were twins in a culture that held twinhood to be extraordinary.<\/p>\n
The genetic data reads their relatedness from fragments of degraded DNA extracted from the densest bone in the human skull.<\/p>\n
<\/p>\n
It calculates a coefficient of relatedness that approaches one, the signature of a shared zygote, a shared beginning, a shared genetic inheritance that set them apart from most other pairs of human beings in any population.<\/p>\n
The limestone kept them for centuries.<\/p>\n
The science read them back to the living world.<\/p>\n
And the living Maya communities of the Yucat\u00e1n \u2014 speaking languages that descend from the same linguistic traditions, inhabiting landscapes that their ancestors inhabited for millennia, maintaining cultural practices that draw on the same deep history \u2014 are the ongoing story of which the children in the chult\u00fan are a part.<\/p>\n
Ancient genomics did not discover the Maya.<\/p>\n
<\/p>\n
It added, with specific precision, to what is known about specific people who were part of a civilization that never disappeared.<\/p>\n
\u2014 END \u2014<\/p>\n
\u2014 EXTENDED SECTIONS \u2014<\/p>\n
Chich\u00e9n Itz\u00e1: The City That Changed the Maya World<\/p>\n
Before understanding what a chult\u00fan full of children’s bones means for Maya archaeology, it helps to understand the specific character of the city in which it was found.<\/p>\n
Chich\u00e9n Itz\u00e1 is not simply a large Maya site.<\/p>\n
It is a city that, at specific points in its history, represented a genuinely new kind of political and architectural statement in the northern Maya lowlands \u2014 one that drew on traditions from across a wide region of Mesoamerica and that produced built forms that have no straightforward parallels among earlier Maya sites.<\/p>\n
The architectural vocabulary of Chich\u00e9n Itz\u00e1’s main ceremonial precinct is strikingly cosmopolitan.<\/p>\n
<\/p>\n
Features associated with the Central Mexican highland traditions \u2014 including the serpent columns, the chacmool sculpture types, and certain decorative programs \u2014 appear alongside forms clearly derived from the earlier lowland Maya tradition.<\/p>\n
This has generated a long scholarly debate about whether the Terminal Classic florescence at Chich\u00e9n Itz\u00e1 represented conquest or colonization from central Mexico, influence through trade and cultural exchange, or the independent development of a cosmopolitan architectural tradition within northern Yucat\u00e1n.<\/p>\n
The current scholarly consensus, developed over decades of comparative architectural analysis and epigraphy, tends away from the conquest hypothesis and toward understanding Chich\u00e9n Itz\u00e1’s distinctive character as the product of a city that was genuinely cosmopolitan in its networks and influences \u2014 a city that drew on multiple traditions because it occupied a position in regional exchange and pilgrimage networks that brought diverse inputs to its builders and planners.<\/p>\n
The ball game, which is prominently featured in the Popol Vuh’s Hero Twin narrative and which was central to Mesoamerican religious and political life across many cultures and periods, is represented at Chich\u00e9n Itz\u00e1 by the largest ball court in the ancient Americas.<\/p>\n
<\/p>\n
The Great Ball Court is 168 meters long and 70 meters wide.<\/p>\n
The walls flanking the playing field bear elaborate carved reliefs that include scenes of decapitation \u2014 a motif connecting the ball game to sacrificial practice and to the mythological themes of death and transformation that permeate both the Popol Vuh narrative and the broader Mesoamerican sacrificial complex.<\/p>\n
The specific form of sacrifice most prominently associated with Chich\u00e9n Itz\u00e1 in popular imagination \u2014 the throwing of individuals into the Sacred Cenote \u2014 is supported by archaeological evidence from the cenote itself, though the character of that evidence is more complex than the simple narrative of live sacrifice that often appears in popular accounts.<\/p>\n
The objects recovered from the cenote include human bones alongside a remarkable variety of other materials, and the human remains show a demographic profile that includes adults and children of both sexes, as well as evidence of processing and treatment of remains that complicates any single interpretive framework.<\/p>\n
<\/p>\n
The chult\u00fan analyzed in the 2024 study is thus situated within a site that was already complex in its ritual practices, a city whose relationship to sacrifice, to the underworld, and to cosmological themes of death and transformation was multifaceted and probably evolved over the centuries of its occupation.<\/p>\n
The Terminal Classic Period and Chich\u00e9n Itz\u00e1’s Moment<\/p>\n
The Terminal Classic period, roughly from 800 to 1000 CE in the northern Maya lowlands, was characterized by two converging trajectories: the collapse of the great Classic Maya cities of the southern lowlands, and the florescence of new political and architectural developments in the north.<\/p>\n
The “Classic Maya Collapse” \u2014 the abandonment of the major Classic-period cities of the southern lowlands, including Tikal, Palenque, Caracol, and dozens of others \u2014 is one of the most studied events in Maya archaeology.<\/p>\n
Its causes were multiple and varied by region, involving some combination of prolonged drought, overpopulation and agricultural stress, political instability and warfare, epidemic disease, and the breakdown of the long-distance exchange networks that had sustained the Classic Maya elite economy.<\/p>\n
<\/p>\n
By around 900 CE, most of the great southern cities had been reduced to small populations or were entirely abandoned.<\/p>\n
In the northern lowlands, including the Yucat\u00e1n Peninsula where Chich\u00e9n Itz\u00e1 is located, conditions were different.<\/p>\n
The northern lowlands have access to cenote water that the southern lowlands lack \u2014 a crucial difference in a region where water management was essential to large population support.<\/p>\n
The northern lowlands also had different trade connections, including direct access to the Gulf of Mexico coast and its maritime trade routes, and a somewhat different agricultural ecology.<\/p>\n
As the southern cities declined, Chich\u00e9n Itz\u00e1 emerged as one of the dominant political and religious centers of the northern lowlands.<\/p>\n
<\/p>\n
The scale of construction at the site in its Terminal Classic phase suggests a period of intensive investment and growth.<\/p>\n
The city drew people, goods, and tribute from across a wide region.<\/p>\n
Its architectural program communicated both power and cosmological claims \u2014 this was a city that understood itself as occupying a special place in the structure of the universe.<\/p>\n
It is in this context \u2014 the apex of Chich\u00e9n Itz\u00e1’s power and influence, during the Terminal Classic and the early Postclassic \u2014 that the use of the chult\u00fan for ritual interment likely falls.<\/p>\n
The city at this period was at the height of its capacity to organize and conduct large-scale ritual activities, to draw populations from a wide area, and to maintain the ceremonial infrastructure that included the Sacred Cenote and the various subterranean features associated with it.<\/p>\n
<\/p>\n
Ancient DNA in Mesoamerica: The Methodological Frontier<\/p>\n
The generation of high-quality ancient genome data from human remains in Mesoamerica has been more difficult than comparable work in other regions of the world, and the methods developed to address those difficulties are worth explaining.<\/p>\n
The challenge begins with preservation.<\/p>\n
DNA degrades over time at rates that depend heavily on temperature and moisture.<\/p>\n
Warm, humid tropical environments \u2014 like the Yucat\u00e1n Peninsula \u2014 are among the most challenging for ancient DNA preservation.<\/p>\n
Bacterial and fungal activity in warm, moist soils rapidly destroys the organic molecules of bone, including DNA.<\/p>\n
<\/p>\n
The bones themselves, even when physically well-preserved in appearance, may contain little or no recoverable genetic material.<\/p>\n
The petrous bone, with its exceptional density and internal structure, has been found in global ancient DNA research to preserve genetic material better than other skeletal elements, often when other bones yield nothing.<\/p>\n
This discovery, which was made through comparative studies of different bone elements at the same sites, has transformed the practice of ancient DNA sampling by directing researchers to prioritize the petrous bone whenever it is available.<\/p>\n
Even from the petrous bone, the yield of recoverable ancient DNA in tropical environments may be low.<\/p>\n
<\/p>\n
The researchers who worked on the Chich\u00e9n Itz\u00e1 chult\u00fan samples used extraction methods optimized for low-yield material, including digestion in silica-containing buffers and library preparation techniques designed to capture very short and highly fragmented DNA molecules \u2014 the kinds of fragments that survive when most of the original DNA has already been degraded.<\/p>\n
The success rate of 64 out of the total samples processed represents a significant achievement for this type of material.<\/p>\n
Not every sampled petrous bone yielded sufficient DNA for genome-wide analysis; the 64 successful samples were those where enough genetic material survived to produce the data needed for kinship analysis and population genetic work.<\/p>\n
The genome-wide data generated from each successful sample consisted of sequencing reads \u2014 short stretches of DNA sequence \u2014 that could be mapped to the human reference genome to determine which part of the genome they came from.<\/p>\n
The depth of coverage \u2014 how many times on average each position in the genome was represented \u2014 varied among the samples, and the specific analyses that could be conducted depended on the coverage achieved for each individual.<\/p>\n
<\/p>\n
Kinship analysis from ancient genome data uses the patterns of genetic variants shared between individuals to calculate relatedness coefficients.<\/p>\n
For pairs that share a high proportion of genetic variants in specific patterns, the data supports first-degree or second-degree relatedness.<\/p>\n
For pairs that share the near-complete genetic identity expected of monozygotic twins, the coefficient approaches one \u2014 distinguishing identical twins from all other kinds of relatives.<\/p>\n
The Isotopic Architecture of a Diet<\/p>\n
The stable isotope analysis that complemented the genomic work in the 2024 study operates through the principle that “you are what you eat” in a specific chemical sense: the ratios of stable isotopes of carbon, nitrogen, and other elements in the human body reflect the ratios of those elements in the foods consumed during life.<\/p>\n
Carbon stable isotopes, expressed as the ratio of carbon-13 to carbon-12, vary between different categories of food.<\/p>\n
<\/p>\n
Plants that photosynthesize using the C3 pathway \u2014 which includes most trees, shrubs, and temperate grasses \u2014 incorporate carbon-13 at a lower ratio than plants using the C4 pathway, which includes maize (corn), sorghum, and tropical grasses.<\/p>\n
In the Maya diet, maize was a critical staple crop, and the relative importance of maize in an individual’s diet is reflected in the carbon isotope ratios of their bones.<\/p>\n
Higher carbon-13 values indicate greater maize consumption; lower values indicate more reliance on C3 foods.<\/p>\n
Nitrogen stable isotopes, expressed as the ratio of nitrogen-15 to nitrogen-14, increase with trophic level \u2014 with each step up the food chain, the nitrogen-15 to nitrogen-14 ratio increases slightly.<\/p>\n
Individuals who consume large amounts of animal protein show higher nitrogen-15 values than those who rely primarily on plant foods.<\/p>\n
<\/p>\n
In aquatic contexts, marine foods typically produce higher nitrogen-15 values than terrestrial foods at the same trophic level.<\/p>\n
For the chult\u00fan assemblage, the isotope data provided several useful types of information.<\/p>\n
First, by comparing the isotope profiles of individuals identified as close relatives through genomic analysis, researchers could assess whether relatives shared similar dietary patterns \u2014 which they did, consistent with having been raised in the same household.<\/p>\n
This cross-validation between the genetic and isotopic data strengthened both findings.<\/p>\n
Second, the overall dietary patterns suggested by the isotope data placed the children within a Maya dietary context recognizable from other sites in the region.<\/p>\n
<\/p>\n
The combination of significant maize consumption with variable but generally substantial animal protein intake is consistent with what is known about Classic and Terminal Classic Maya diets at major sites.<\/p>\n
Third, in contexts where sufficient regional isotope baseline data exists, the geographic sourcing of individuals is possible through strontium isotope analysis, which reflects the local geological environment where drinking water was obtained during childhood tooth formation.<\/p>\n
The 2024 study’s integration of isotope and genomic data provides a multi-dimensional picture of the children’s biological identity that neither approach alone could have produced.<\/p>\n
The Popol Vuh’s World in Deeper Detail<\/p>\n
<\/p>\n
The Popol Vuh was recorded in writing by K’iche’ Maya scribes in the sixteenth century, shortly after the Spanish conquest, in an effort to preserve the oral and possibly written traditions of their community.<\/p>\n
The text opens with a cosmological account of creation and moves through the deeds of a series of supernatural beings before reaching the story of the Hero Twins.<\/p>\n
The Hero Twins’ father and uncle \u2014 Hun Hunahpu and Vucub Hunahpu \u2014 are ballplayers who are summoned to the underworld and killed by its lords.<\/p>\n
Hun Hunahpu’s head is placed in a gourd tree, and from this tree his head spits into the hand of Ixquic, a maiden of the underworld, who becomes pregnant with the Hero Twins and eventually flees to the surface world to give birth.<\/p>\n
The twins, Hunahpu and Xbalanque, are themselves ballplayers \u2014 clearly defined as male in the narrative \u2014 and they eventually receive the same summons to the underworld that destroyed their father and uncle.<\/p>\n
<\/p>\n
In the underworld, they face a series of deadly challenges in specialized “houses” \u2014 a dark house, a cold house, a house of fire, a house of jaguars, a house of bats.<\/p>\n
Through cleverness, they survive most of these challenges, though Hunahpu’s head is removed by a bat in one episode and temporarily replaced with a squash until it can be restored.<\/p>\n
The twins ultimately triumph in the underworld ball game, fake their own deaths, are killed and disposed of in water, and are reborn as traveling performers who entertain the underworld lords with miraculous feats \u2014 including cutting themselves and restoring themselves whole.<\/p>\n
When the lords of the underworld ask to receive the same treatment, the twins kill them without restoring them, completing their victory.<\/p>\n
<\/p>\n
After defeating the lords of Xibalba, the twins honor their father and uncle by transforming them into celestial bodies, and they themselves ascend to become the sun and the moon, establishing the current cosmic order.<\/p>\n
The narrative’s themes of descent, death, transformation, and rebirth \u2014 of the relationship between the underworld and the celestial order, and of the role of twins as the agents of that transformation \u2014 resonate with the evidence from the chult\u00fan in ways that are more than coincidental.<\/p>\n
But the resonance between a sixteenth-century K’iche’ text and a ninth- or tenth-century Chich\u00e9n Itz\u00e1 ritual context requires careful handling.<\/p>\n
The Popol Vuh represents one strand of a broadly shared Mesoamerican mythological tradition, not a direct account of the specific ritual beliefs at one specific site.<\/p>\n
<\/p>\n
The Ball Game and Its Connections<\/p>\n
The ball game \u2014 juego de pelota \u2014 was one of the most significant shared cultural practices across ancient Mesoamerica, appearing in archaeological evidence from sites stretching from the American Southwest to Honduras, and from periods extending back at least three millennia before the Terminal Classic.<\/p>\n
The rubber ball used in the game was a product of the lowland forest regions where the rubber tree grows.<\/p>\n
The ball was heavy and solid, and players moved it around a court using their hips, knees, or elbows rather than their hands or feet.<\/p>\n
<\/p>\n
Different versions of the game in different regions and periods may have used different implements and different rules, but the core technology \u2014 rubber ball, masonry court \u2014 was broadly consistent.<\/p>\n
Ball courts appear at Chich\u00e9n Itz\u00e1 in several locations, with the Great Ball Court being the largest.<\/p>\n
The carved relief panels on the walls of the Great Ball Court include scenes of players and, in the most discussed panels, a decapitation scene in which a kneeling player is shown with a stream of blood emerging from his severed neck, the blood transforming into serpents and flowering plants \u2014 a visual vocabulary of death as transformation that connects to both the sacrificial context of the game and to the broader Mesoamerican theme of death as productive and generative rather than merely terminal.<\/p>\n
The ball game’s connection to the Hero Twin story, to sacrifice, to the underworld, and to the themes of death and rebirth that characterize Mesoamerican religious thought more broadly makes it relevant context for understanding the ritual environment of Chich\u00e9n Itz\u00e1.<\/p>\n
<\/p>\n
The city’s investment in the ball game infrastructure \u2014 including the largest court in the ancient Americas \u2014 was part of a comprehensive architectural and ritual program that positioned the city as the center of a specific kind of cosmological authority.<\/p>\n
Whether the children in the chult\u00fan had any direct connection to ball game ritual is not established by the evidence.<\/p>\n
But the ball game, the underworld, the Sacred Cenote, and the children’s bones are all part of the same site, the same city, the same ritual world.<\/p>\n
The Regional Picture: Other Maya Cenote Findings<\/p>\n
The Sacred Cenote at Chich\u00e9n Itz\u00e1 is the most famous but not the only cenote in the Maya world to have yielded evidence of ritual activity.<\/p>\n
The pattern of cenote use as ritual deposition sites, including the deposition of human remains, appears across the northern Maya lowlands and provides a broader regional context for interpreting the findings from Chich\u00e9n Itz\u00e1.<\/p>\n
<\/p>\n
The Cenote Sagrado (Sacred Cenote) itself has been the subject of archaeological investigation since the early twentieth century, including dredging operations and more recent underwater archaeology.<\/p>\n
The objects recovered from the cenote are extraordinary in their variety and quality: jade objects of exceptional craftsmanship, gold and copper artifacts including items from distant regions of Mesoamerica, worked bone, rubber items, wooden objects, textile fragments, and the human skeletal remains that have attracted the most attention.<\/p>\n
The human remains from the Sacred Cenote show a demographic profile that differs from the chult\u00fan: adults are represented alongside children, females are represented alongside males.<\/p>\n
The specific character of what was deposited in the cenote versus what was deposited in the chult\u00fan suggests that these were not simply two instances of the same ritual practice but rather distinct ritual contexts operating within the broader ceremonial landscape of Chich\u00e9n Itz\u00e1.<\/p>\n
<\/p>\n
Other cenotes in the northern Maya lowlands have been investigated archaeologically, with varying results.<\/p>\n
Some have produced primarily object assemblages with little or no human skeletal material.<\/p>\n
Others have produced human remains in specific demographic patterns.<\/p>\n
The variation across sites suggests that different communities and different periods approached cenote ritual deposition with different practices, and that there was no single, fixed protocol for cenote ritual in the Maya world.<\/p>\n
The Broader Context of Child Sacrifice in Mesoamerica<\/p>\n
The practice of child sacrifice in ancient Mesoamerica has been documented at multiple sites across the region, in contexts that vary significantly in their specific character but that collectively indicate the widespread cultural significance of the practice.<\/p>\n
<\/p>\n
At Tenochtitl\u00e1n, the Aztec capital, evidence for child sacrifice has been found in ritual caches and in association with the great temple precinct.<\/p>\n
The Aztec sources recorded by Spanish colonizers describe ritual practices involving children, particularly associated with rain deity worship and with the first-fruits ceremonies of the agricultural calendar.<\/p>\n
The specific details of these practices \u2014 the identity of the children, their social origins, the specific ritual forms \u2014 are documented in Spanish colonial sources with varying reliability, reflecting the perspectives of the documenters as well as the practices of the documented.<\/p>\n
At Tiwanaku, the ancient site in present-day Bolivia, isotope analysis of child burials has provided evidence that some sacrificed children were brought from distant regions for inclusion in specific ritual contexts \u2014 the Capacocha practice of the later Inca civilization, which involved child sacrifice at mountain shrines, is well-documented and included the transport of children from great distances to their sacrificial destinations.<\/p>\n
<\/p>\n
Whether similar patterns of transport applied in the Maya context is not established.<\/p>\n
The Chich\u00e9n Itz\u00e1 findings add to this broader picture by providing unprecedented genetic detail about the demographic composition and kinship structure of a specific child sacrifice context.<\/p>\n
No previous study of ancient Mesoamerican child sacrifice has generated genome-wide data from 64 individuals, identified close relative pairings among them, and found two pairs of identical twins.<\/p>\n
The methodological advance represented by the 2024 study is significant for the broader study of Mesoamerican ritual practice, not just for Chich\u00e9n Itz\u00e1 specifically.<\/p>\n
The Aftermath of the Colonial Contact<\/p>\n
<\/p>\n
The period following the Spanish conquest of Yucat\u00e1n \u2014 a conquest that took decades and was never as complete as the conquests of central Mexico, given the Yucat\u00e1n’s lack of a single dominant political center that could be captured and used as a control point \u2014 saw the rapid transformation of Maya society under colonial rule.<\/p>\n
The epidemics that swept through Maya communities from the sixteenth century onward killed enormous proportions of the population.<\/p>\n
The specific severity varied by region and by the timing and character of European contact, but the overall pattern was catastrophic.<\/p>\n
Some estimates suggest that the population of the Yucat\u00e1n Peninsula declined by 80 to 90 percent in the century following initial contact, due to the combined effects of disease, violence, forced labor, and social disruption.<\/p>\n
Spanish colonial religious policy actively worked to suppress Maya religious practices.<\/p>\n
<\/p>\n
The autodaf\u00e9 at Man\u00ed in 1562, at which the Spanish bishop Diego de Landa ordered the burning of Maya hieroglyphic books (codices) and ritual objects, is the most famous single episode of this suppression.<\/p>\n
The destruction of the Maya written tradition \u2014 represented in the surviving codices, only four of which are known to have survived \u2014 was part of a broader effort to replace Maya spiritual and cultural life with Christianity.<\/p>\n
Despite this suppression, Maya cultural and religious practices did not simply disappear.<\/p>\n
They were transformed, adapted, partially preserved in disguised forms, and maintained in various ways across the colonial period and into the present.<\/p>\n
The K’iche’ community that recorded the Popol Vuh did so in the context of this suppression, using the Latin alphabet to write in their own language, preserving traditional narratives in a form that was less immediately recognizable as the pagan material that colonial authorities sought to eradicate.<\/p>\n
<\/p>\n
The immune gene findings from the 2024 study reflect the biological legacy of this period.<\/p>\n
The selective pressure of the post-contact epidemics left detectable signatures in the immune-related genetic variants of the surviving population’s descendants.<\/p>\n
The modern Maya people of Tixcacaltuyub carry in their genomes the trace of what their ancestors survived \u2014 a biological record of an historical catastrophe that is also documented in the colonial archives.<\/p>\n
The Scholarship of Maya Sacrifice: A Complex History<\/p>\n
The study of sacrifice in ancient Maya civilization has a complicated scholarly history, shaped both by the evidence itself and by the contexts in which that evidence has been interpreted and communicated.<\/p>\n
<\/p>\n
Early accounts of Maya civilization by Spanish colonial observers frequently emphasized spectacular and violent elements of Maya religious practice.<\/p>\n
The colonial project of religious conversion required the discrediting of indigenous religious traditions, and descriptions of sacrifice served this purpose.<\/p>\n
The result was that some early accounts exaggerated, distorted, or decontextualized the sacrificial practices they described.<\/p>\n
Later scholarship, in the twentieth century, sometimes reacted against these early accounts by minimizing or denying the evidence for sacrifice in Maya civilization \u2014 particularly against the evidence of human sacrifice, which had been associated with the Aztec civilization and was sometimes assumed to be alien to the Maya tradition.<\/p>\n
This reaction was understandable as a correction to colonial-era distortions, but it sometimes went too far, dismissing evidence that was real.<\/p>\n
<\/p>\n
The accumulation of archaeological evidence over the past several decades has established, beyond reasonable doubt, that human sacrifice was practiced in the Maya world \u2014 at Chich\u00e9n Itz\u00e1 and at other sites, across multiple periods, and in multiple specific contexts.<\/p>\n
The evidence from the Sacred Cenote, from the ball court relief panels, and now from the chult\u00fan analyzed in the 2024 study is consistent with this established understanding.<\/p>\n
At the same time, the scholarship that has developed around these findings has worked to situate the sacrificial practices within their proper cultural and cosmological context \u2014 to understand them not as gratuitous violence or as the defining feature of Maya civilization, but as specific ritual practices embedded in a complex religious system that also produced extraordinary achievements in art, architecture, astronomy, mathematics, and literature.<\/p>\n
The challenge for contemporary scholars and science communicators is to report the evidence accurately without either minimizing practices that the evidence shows were real or presenting those practices in ways that reduce a rich and complex civilization to its most dramatic and violent elements.<\/p>\n
<\/p>\n
The Living Tradition of Maya Spiritual Practice<\/p>\n
Contemporary Maya communities maintain living spiritual traditions that draw on the deep heritage of Maya religious thought, adapted to and integrated with the Christianity that was imposed through the colonial period.<\/p>\n
In communities across the Yucat\u00e1n, Guatemala, Belize, and the rest of the Maya world, traditional ceremonies, calendrical observances, and healing practices continue to be performed.<\/p>\n
Maya daykeepers \u2014 ritual specialists who maintain the traditional 260-day calendar and use it to guide ceremonial and divinatory practices \u2014 are active in communities throughout the Maya region.<\/p>\n
The specific forms of these practices vary by community and region and have been influenced by both the pre-contact tradition and by centuries of colonial contact and cultural mixing.<\/p>\n
<\/p>\n
The relationship between these living spiritual practices and the archaeological evidence of ancient Maya religion is not straightforward.<\/p>\n
Some elements of continuity are apparent \u2014 the continuing importance of cenotes and other water sources in ritual practice, for example, or the persistence of the 260-day calendar, or the maintenance of specific cosmological concepts about the structure of the universe and the role of ancestors.<\/p>\n
But the colonial suppression of Maya religion was also genuine and had real effects, disrupting the transmission of specific knowledge and practices in ways that mean that the living tradition is not simply a direct continuation of the pre-contact tradition.<\/p>\n
Living Maya spiritual practitioners are among the voices that deserve to be heard in discussions about the interpretation of the ancient evidence.<\/p>\n
<\/p>\n
Their perspectives on what the chult\u00fan findings mean \u2014 not as definitive interpretive authority over archaeological evidence, but as community members with legitimate interests in how their ancestors’ lives and deaths are represented \u2014 are part of the ethical and intellectual context of the research.<\/p>\n
A Different Kind of Monument<\/p>\n
The excavated pyramids and temples of Chich\u00e9n Itz\u00e1 are monuments in the most obvious sense: large, visible, designed to impress and to communicate.<\/p>\n
They have been the subject of study and interpretation for more than a century and are among the most recognized architectural achievements of the ancient Americas.<\/p>\n
The chult\u00fan is a different kind of monument.<\/p>\n
It is invisible from the surface.<\/p>\n
<\/p>\n
It is underground, carved into the bedrock, accessible only through a specific opening.<\/p>\n
Its significance is not communicated through visual grandeur but through the accumulated evidence of what it contained: generations of children, deposited over centuries, in a ritual practice whose specific character is still being understood.<\/p>\n
The children in the chult\u00fan are not named in any inscription.<\/p>\n
They appear in no known relief panel or monument.<\/p>\n
The oral traditions that may have celebrated or mourned their role in the ritual of their time are not preserved in any surviving text.<\/p>\n
What preserves them \u2014 what brings them, improbably, back into the historical record \u2014 is the chemistry of their own bones: the DNA and the stable isotopes and the radiocarbon that survived the centuries in the dense limestone of the Yucat\u00e1n.<\/p>\n
<\/p>\n
That the same civilization that built the Great Ball Court and aligned El Castillo with the equinox sun also maintained this specific practice in this specific underground space is not a contradiction.<\/p>\n
It is evidence of the complexity of a civilization that deserves to be understood in its full dimension: its achievements, its practices, its cosmology, its social structures, and its continuing presence in the lives of the people who are its descendants.<\/p>\n
The Article as Record and the Record as Responsibility<\/p>\n
Any writing about the Chich\u00e9n Itz\u00e1 chult\u00fan \u2014 including this one \u2014 participates in the ongoing process of representing the ancient Maya to contemporary audiences.<\/p>\n
That participation carries responsibilities.<\/p>\n
<\/p>\n
The most basic responsibility is accuracy: representing the findings of the 2024 study correctly, distinguishing between what the genetic evidence established and what remains interpretive, and avoiding the exaggeration or distortion that sensational findings sometimes attract.<\/p>\n
A second responsibility is contextualization: situating the findings within the proper archaeological, historical, and cultural context, so that the chult\u00fan is not understood in isolation from the broader civilization that produced it and the broader scholarship that has studied it.<\/p>\n
A third responsibility is recognition of the living community: acknowledging that the ancient Maya are the ancestors of living Maya people, and that those people have legitimate interests in how their ancestors are represented.<\/p>\n
A fourth responsibility is epistemic humility: acknowledging what is not known and cannot be known, and avoiding the temptation to fill the gaps in the evidence with invented certainty.<\/p>\n
<\/p>\n
The 2024 Nature study that is the subject of this article met these responsibilities to a high standard in its scientific publication.<\/p>\n
The task of translating those findings for a general audience while maintaining the same standards is more difficult, because the conventions and context of scientific publication are not always transferable to long-form narrative writing.<\/p>\n
The attempt has been made here to maintain accuracy, context, community recognition, and epistemic humility throughout \u2014 but the reader who is interested in the specific scientific findings is encouraged to consult the primary publication in Nature for the authoritative account of the methodology and results.<\/p>\n
The Passage of Centuries<\/p>\n
<\/p>\n
The children in the chult\u00fan were interred over a period of centuries.<\/p>\n
Multiple generations of people at Chich\u00e9n Itz\u00e1 participated in the practice that brought them there, opening the underground space for new interments and closing it again, maintaining the space across the succession of political and religious leadership that characterized any city over the course of centuries.<\/p>\n
The city itself lasted longer than the specific ritual practice may have \u2014 Chich\u00e9n Itz\u00e1’s occupation and political significance extended well into the Postclassic period, even as the great Terminal Classic building program gave way to different architectural and political arrangements.<\/p>\n
The chult\u00fan’s centuries of use overlapped with some of the most active periods of the city’s development, connecting the underground space to the broader history of a city at the height of its regional importance.<\/p>\n
<\/p>\n
What happened at the end: when did the last child come to rest in the underground space?<\/p>\n
The radiocarbon data provides a window for the use of the feature, but the specific final interment \u2014 the last time the space was opened and the last small body placed within it \u2014 is not recoverable as a distinct event from the dating evidence.<\/p>\n
At some point, the practice stopped.<\/p>\n
The space was sealed, or simply no longer used.<\/p>\n
The centuries accumulated over the bones in the limestone darkness.<\/p>\n
And then, in modern times, archaeologists opened the space and found what had been left there.<\/p>\n
<\/p>\n
And then, in even more modern times, researchers extracted tiny cores of material from the densest bones of the smallest skulls and sent them to laboratories where machines read the fragments of ancient DNA \u2014 fragments that had survived the centuries because the petrous bone had held them against the dissolution that claimed the rest.<\/p>\n
The limestone kept the secret for five centuries.<\/p>\n
The science read it.<\/p>\n
Two pairs of twins were known for the first time in the modern world as twins \u2014 separated from that knowledge by the long years and the long darkness, and then found again in the sequences of a genome.<\/p>\n
The Full Circle<\/p>\n
The finding of two pairs of identical twins in the Chich\u00e9n Itz\u00e1 chult\u00fan is, at one level, a statistical result: a coefficient of relatedness approaching one, a genome-wide comparison that identified four individuals as two pairs of monozygotic twins.<\/p>\n
At another level, it is a human story.<\/p>\n
<\/p>\n
Two sets of children who were born together, who grew up together, who experienced the world as the specific pair of people that twinhood creates \u2014 individuals who are distinct and separate but who share a biological beginning and a visible sameness that sets them apart from everyone else \u2014 were brought to the same underground space in a city that understood them, in ways we cannot fully reconstruct, as cosmologically significant.<\/p>\n
In the Maya world, twins were not simply a demographic category.<\/p>\n
They were a kind of person that the universe produced in specific circumstances and for, possibly, specific purposes.<\/p>\n
The Hero Twin narrative made twinhood the foundation of the current cosmic order \u2014 the sun and moon, which govern time and light and the structure of the sky, were twins who descended into the underworld and triumphed over it.<\/p>\n
Whether the pairs of twins in the chult\u00fan were understood by the people who brought them there as representations of Hunahpu and Xbalanque, as embodiments of those mythological archetypes, or as something else entirely that we cannot now name: this is not recoverable.<\/p>\n
<\/p>\n
But the cosmological weight of twinhood in Maya civilization is real, documented in the artistic record and in the surviving textual tradition, and it is impossible to contemplate two pairs of identical twins in a subterranean ritual space near the Sacred Cenote without understanding that this weight was part of the context in which those children were seen and understood.<\/p>\n
The DNA identified them as twins across a gap of a thousand years.<\/p>\n
They were twins when they lived.<\/p>\n
They were twins in whatever role the ritual assigned them.<\/p>\n
They are twins now, known as such for the first time since the people who knew them were alive.<\/p>\n
The limestone held them.<\/p>\n
The science found them.<\/p>\n
The story they are part of continues in the living communities of the Maya world, and in the scholarship that tries to understand the past those communities carry, and in the conversations between researchers and communities that are still, imperfectly and necessarily, being negotiated.<\/p>\n
<\/p>\n
The children in the underground space were people.<\/p>\n
The twins among them were a specific kind of people in their culture’s eyes.<\/p>\n
And in ours, they are now, at last, known for what they were.<\/p>\n
\u2014 COMPLETE FINAL END \u2014<\/p>\n
\u2014 FINAL EXTENDED SECTIONS \u2014<\/p>\n
The Petrous Bone: A Scientific Marvel Inside the Human Skull<\/p>\n
The fact that ancient DNA was successfully recovered from all 64 sampled individuals in the chult\u00fan is worth dwelling on, because it represents a significant technical achievement in a preservation environment that is generally hostile to ancient genetic material.<\/p>\n
The petrous bone is the densest bone in the human body.<\/p>\n
<\/p>\n
Its specific density derives from the extremely compact arrangement of its mineral crystals \u2014 a structural adaptation that evolved to protect the delicate sensory apparatus of the inner ear from vibration and mechanical disturbance.<\/p>\n