'Alien' skull of toddler is actually evidence of long-standing practice of head shaping

While installing a water pipeline in Argentina last month, workers stumbled upon the skull of a child who was buried at least 700 years ago. The archaeological discovery quickly garnered media attention because of the asymmetry of the skull, drawing comparisons to aliens.

But the flattening on the back of the skull, which belonged to a 3- to 4-year-old child, is simply the result of the cultural practice of head shaping, Cristian Sebastián Melián, director of the Provincial Directorate of Anthropology in Catamarca, Argentina, told Live Science in a translated email.

The skull was found on May 27 in the town of San Fernando del Valle de Catamarca in northwestern Argentina. When archaeologists investigated the pits made in the infrastructure project, they found broken and burned llama remains, along with a ceramic vessel typical of pottery from the Inca occupation there between 1430 and 1530, Melián said.

But the child's skull was found several feet away along with the rest of the skeleton, which was placed in the grave in the fetal position. Although the child had no grave goods, pottery fragments in the dirt suggested a date of death around 1100 to 1300.

The archaeologists did not see any trauma on the child's skeleton, but they noted the "pronounced cultural cranial alteration of the oblique tabular type," Melián said.

The practice of head shaping, or cranial modification, dates back thousands of years and has been found in all parts of the world. While some cultures used long stretches of cloth wrapped around a baby's head to create an elongated shape, others applied padding to the front or back of the baby's head to create a flatter shape. Nowadays, often for medical purposes, parents may employ a special helmet to ensure their baby has a round, symmetrical head.

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The child's skull found in San Fernando was likely shaped using padding to encourage the "oblique tabular" shape, which is flat or sloping at the front and back of the skull. This practice can cause the sides of the skull to widen and appear bulged.

Most scholars of ancient head shaping agree that the practice had few, if any, negative health consequences. Instead, experts say the practice was linked to social identity or to child-rearing preferences.

Currently, the Provincial Directorate of Anthropology has more than 100 skulls from ancient people in its skeletal collection, Melián said, and evidence of head shaping is extremely common.

"Approximately 90% of them have an erect or oblique tabular shape" to their skulls, Melián said.