A cave in southern Mexico held a skull rack of 165 skulls, and most were women’s

Of 165 skulls recovered from a cave in Frontera Comalapa, in the southern Mexican state of Chiapas, 83 belonged to women and 79 to men. The remaining three were too fragmentary to assign a sex. Mexico’s National Institute of Anthropology and History, known as INAH, announced the count on 28 October 2026, describing the deposit as a tzompantli, a rack on which skulls were displayed.

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The skulls have been in the hands of specialists since 2012, when they were first documented inside the cave. Fourteen years of study separate the discovery from the new tally, and the delay matters: earlier press coverage of Chiapas cave skulls described them as a possible modern crime scene before specialists placed the remains in the pre-Hispanic past. The collection also includes 15 infants and 51 long bones, all held at the physical anthropology laboratory of INAH’s Chiapas Centre.

Sexing 165 skulls without pelvic bones

Estimating sex from a skull alone is harder than from a pelvis, and none of the pelvic bones survived with this assemblage. According to the INAH bulletin, physical anthropologists Cristell Delesma Pérez and Abigail Reyes López relied on two features, the angle and shape of the lower jaw and the ridge of bone above the eyes, to sort individuals into female and male groups. Skulls too broken to show either trait went into the undetermined column, which is why the two named totals add up to 162 rather than 165.

The result, 83 women against 79 men, is a narrow margin, and the method carries error bars that the announcement does not quantify. What stands out is the direction rather than the size of the gap. Popular accounts of Mesoamerican skull racks often picture adult male captives, warriors taken in battle, so a deposit that leans female invites a different reading of who was brought to the cave and why.

Age adds a second pattern. Most adults died young, with a predominant range of about 25 to 35 years, and at least two reached 55 to 70, well beyond the roughly 40-year average life expectancy that researchers use for the Maya area in the Early Postclassic period, 900 to 1200 CE. The cut marks recorded on three individuals are the only direct trace of violence reported so far, according to HeritageDaily’s account of the release.

Missing jaws, pulled teeth and shaped heads

Most of the skulls have no lower jaw, and many have upper teeth that were removed deliberately. Several show erect tabular cranial modification, a shaping of the head achieved in childhood by binding boards against the skull. INAH archaeologist Josuhé Lozada Toledo reads these traits as evidence of complex rituals in which bones were brought back into the cave and taken out again for ceremonial purposes, rather than a single event of deposition.

An earlier note from INAH’s photo-of-the-day feature adds a physical detail: unlike the Mexica racks of the Basin of Mexico, these skulls carry no perforations, so researchers propose that wooden structures held them without drilling. It also dates the cranial shaping to roughly 900 to 1200 CE. A Secretariat of Culture release on the theory of a tzompantli at the Cueva de Comalapa records the same idea of a rack built from aligned wooden rods.

A pilgrimage cave and the tonalli

Soot on the ceiling, visible in historical photographs, and signs of burning on some bones point to repeated visits with torches. From that evidence, INAH researchers suggest the cave functioned as a pilgrimage site where ceremonies, possibly including petitions for rain, took place over time. Culture Secretary Claudia Curiel de Icaza said the cave may have been a space for pilgrimage and ritual practice for surrounding Maya communities.

Lozada Toledo ties the skulls to Mesoamerican ideas about the body, in which an individual’s animating essences sat in different organs. The tonalli, associated with the head, was one of them. On that reading the tzompantli could have been a large accumulation of souls offered to deities within sacred places such as caves. He also said the osteological results allow a re-evaluation of the role of women in ancient ritual.

Comalapa and the Huei Tzompantli of Tenochtitlan

Lozada Toledo places the Comalapa deposit earlier than the great skull racks of central Mexico, which belong to the Late Postclassic, 1200 to 1521 CE. The best known is the Huei Tzompantli of Tenochtitlan, profiled on INAH’s site page for the monument, where he suggests displays of this kind also served political ends.

A separate INAH bulletin on women’s skulls in the Huei Tzompantli links some of that Tenochtitlan material to the origin myth of Huitzilopochtli, a reminder that female victims are not unknown elsewhere. Whether Comalapa’s female majority reflects the same logic, or a different Maya practice, remains unresolved: no precise radiocarbon date for the deposit appears in the announcement, and the researchers have not yet published a peer-reviewed paper.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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