Ancient bone may reveal how Neanderthals cared for a child with Down syndrome

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A fossilized ear bone discovered in a cave in Spain revealed a Neanderthal child who lived with Down syndrome until he was 6 years old, according to a new study.

The discovery suggested that members of the community cared for and cared for the vulnerable child, who lived at least 146,000 years ago. The research is at odds with the image of Neanderthals, ancient human relatives who went extinct around 40,000 years ago, as brutal cavemen.

“The individual would need continuous and intensive care,” said paleoanthropologist Mercedes Conde-Valverde, lead author of the study. a study in the bone that appeared Wednesday in the journal Science Advances.

The child “suffered from severe hearing loss and had severe balance problems and episodes of vertigo,” explained Conde-Valverde, assistant professor of physical anthropology at the University of Alcalá, in Spain.

Muscle weakness would also make breastfeeding and movement difficult, she added.

The tiny fossil was excavated in 1989 at the archaeological site of Cova Negra, in the Spanish province of Valencia. However, archaeologists only recently discovered the specimen when they sifted through faunal fragments collected at the site during a review of the material.

“We were able to identify it as a Neanderthal due to the peculiar proportions of its semicircular canals, which are characteristic of Neanderthals,” said Conde-Valverde, referring to the inner ear tubes.

The study did not include precise dating of the bone, which would require extracting ancient DNA, but Neanderthals occupied the site between 146,000 and 273,000 years ago. The research team did not determine the sex of the young Neanderthal.

An amazing service life

People with Down syndrome can lead long lives today, but it was surprising that the child lived beyond the age of 6, Conde-Valverde said.

Life in the Stone Age would have been demanding. The study noted that Neanderthals were highly mobile, regularly moving from place to place. The care necessary for the child’s survival over a long period of time likely involved the mother’s reliance on the cooperation and support of other group members.

Even in the recent past, it was common for people with Down syndrome to die in childhood. According to the study, life expectancy in 1929 for children with Down syndrome, a condition caused by a partial or complete extra chromosome, was 9 years. In the 1940s, life expectancy increased to 12 years.

Today, about 1 in every 772 babies in the United States is born with Down syndrome, and life expectancy now exceeds 60 years, according to the National Down Syndrome Society in the United States.

The oldest known case of Down syndrome in Homo sapiens, our species, dates back at least 5,300 years. Using ancient DNA, the authors of a study published in February identified six cases in prehistoric populations. None of the children lived beyond 16 months.

Down syndrome has also been documented in chimpanzees. A January 2016 study highlighted the case of a chimpanzee with Down syndrome who survived up to 23 months thanks to the care received by his mother, with assistance from his eldest daughter.

However, when the daughter stopped helping care for her own children, the mother was unable to provide the necessary care and the children died, the study said.

Inner ear abnormalities

Conde-Valverde and his colleagues believe the bone belonged to a child with Down syndrome due to a series of anomalies in the structure of the inner ear.

These include an abnormal shape of the lateral semicircular canal (the shortest ear canal); a widened vestibular aqueduct, a narrow bony canal running from the inner ear to the depths of the skull, and a reduction in the overall size of the bony chamber of the cochlea.

“Some of these pathologies commonly appear in different syndromes, but the combination present in the Cova Negra fossil has only been described in contemporary people with Down syndrome,” she said.

Definitive proof that the child had Down syndrome would require recovering the fossil’s ancient DNA, but that has not yet been possible, she said.

Previous studies of archaeological discoveries have suggested that Neanderthals cared for vulnerable members of their group.

A Neanderthal buried in Shanidar Cave In what is now Iraq, he was deaf and had a paralyzed arm and a head injury that likely left him partially blind, but he lived a long time, according to October 2017 research.

A Neanderthal skeleton known as the “Old Man of La Chapelle” discovered in present-day central France had degenerative arthritis and may have been fed by other members of your group, a February 2019 study found.

A child cared for ‘like any other’

Conde-Valverde said the discovery of the Cova Negra fossil supported the existence of true altruism among Neanderthals.

“For decades, it has been known that Neanderthals cared for and cared for their vulnerable companions,” Conde-Valverde said.

“However, all known cases of caregiving have involved adult individuals, leading some scientists to believe that this behavior was not genuine altruism but merely an exchange of assistance between equals,” she said.

“What was not known until now was the case of a person who received extramaternal care since birth, although they were unable to reciprocate.”

Most parents today do not view childcare as an “expectation of reciprocity,” and this is unlikely to have been the case among Neanderthals, said Penny Spikins, professor of archeology at the University of York in the United Kingdom and author of “Hidden Depths: The Origins of Human Connection.”

Humans likely developed an instinctive and emotional response when caring for babies to ensure they survived, said Spikins, who was not involved in the research.

“This discovery shows how we Neanderthals were similar in many ways, especially in our common human desire to care for the vulnerable,” she said.

“We can imagine that this child was loved and cared for like any other.”

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