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A fossilized ear bone unearthed in a Spanish cave reveals the presence of a Neanderthal child who lived until the age of six with Down syndrome, according to a new study.
The find suggests that members of the community cared for and looked after the vulnerable child, who lived at least 146,000 years ago.The study contradicts the image of Neanderthals, an ancient human relative who became extinct about 40,000 years ago, as brutal cavemen.
“This individual would have required constant and intensive care,” said paleoanthropologist Mercedes Conde Valverde, lead author of the paper. the study The bones were published in the journal Science Advances on Wednesday.
The child “suffered from profound hearing loss, as well as severe balance problems and dizziness,” explained Conde Valverde, an assistant professor of anthropology at Spain’s University of Alcala.
Loss of muscle strength would also have made breastfeeding and exercise difficult, she added.
The tiny fossil was unearthed in 1989 at the Cova Negra archaeological site in the Valencian region of Spain, but archaeologists only discovered the specimen recently, after combing through animal remains collected at the site during archaeological research.
“We were able to identify this as a Neanderthal because of the unique proportions of the semicircular canals, which are characteristic of Neanderthals,” Conde Valverde said, pointing to the canals inside the ear.
The study did not include precisely dating the bones, which would require extracting ancient DNA, but Neanderthals lived at the site between 146,000 and 273,000 years ago. The team has not yet determined the sex of the young Neanderthal.
People with Down’s syndrome can live long lives today, but Conde Valverde said it was amazing the child lived beyond the age of six.
Life in the Stone Age would have been harsh. Research suggests that Neanderthals were highly mobile, moving from place to place regularly. The care required for young survival over the long term would have meant that mothers relied on the cooperation and support of other members of the group.
Until recently, it was not uncommon for people with Down syndrome, a condition caused by an extra or complete extra chromosome, to die in childhood. Research has shown that in 1929, the average life expectancy for a child with Down syndrome was nine years. By the 1940s, life expectancy had increased to 12 years.
Currently, about 1 in every 772 babies in the United States is born with Down syndrome, and the average life expectancy is over 60 years old. National Down Syndrome Association In the United States.
The oldest known cases of Down Syndrome in our species, Homo sapiens, date back at least 5,300 years. Using ancient DNA A study published in February Six cases were identified in the prehistoric population. None of the children lived longer than 16 months.
Down syndrome has also been documented in chimpanzees. The January 2016 investigation highlighted this case. A chimpanzee with Down’s syndrome has survived to 23 months thanks to the care of his mother and the help of his eldest daughter.
But when the daughter stopped helping to care for her child, the mother was no longer able to provide the care she needed and the child died, the study said.
Mercedes Conde Valverde/Julia Diez Valero
Study of the fossils revealed abnormalities in the ear bones.
Conde Valverde and her colleagues believe the bone belongs to a child with Down syndrome because of a series of abnormalities in the structure of the inner ear.
These include an abnormal shape of the lateral semicircular canal (the shortest ear canal), an enlargement of the vestibular aqueduct, a narrow bony canal that runs from the inner ear deep into the skull, and a reduction in the overall size of the ear. Cochlear bone chamber.
“Some of these conditions are common in various syndromes, but the combination seen in the Cova Negra fossil has been described as being found only in modern humans with Down syndrome,” she said.
To conclusively prove the child had Down syndrome, ancient DNA would need to be recovered from the fossil, which is not yet possible, she said.
Studies of previous archaeological finds suggest that Neanderthals looked out for vulnerable members of their groups.
A Neanderthal man buried in Shanidar Cave An October 2017 investigation found that the man, who lived in what is now Iraq, was deaf, had paralyzed arms and was probably partially blind from a head injury, yet managed to survive.
The Neanderthal skeleton known as the “Old Man of La Chapelle,” discovered in what is now central France, suffered from osteoarthritis. They may have been fed by other members. His group February 2019 was discovered in the study.
Conde Valverde said the discovery of the Cova Negra fossils was proof of the existence of true altruism among Neanderthals.
“We’ve known for decades that Neanderthals cared for and looked after the weaker members of their family,” Conde Valverde said.
“However, all known cases of care have been by individual adults, leading some scientists to believe that this behavior is simply an exchange of assistance between equals rather than true altruism,” she said.
“What has not been known until now are cases of individuals who received non-maternal care from birth, even if they were not cared for by their mother.”
Most parents today don’t think of parenting as an “expectation of mutual support,” and it’s unlikely that was the case among Neanderthals, said Penny Spikins, a professor of archaeology at the University of York in the UK and author of “The Hidden Depths: The Origins of Human Connection.”
Spikins, who was not involved in the study, said humans likely developed an instinctive and emotional response to care for infants to ensure their survival.
“This discovery reminds us how similar Neanderthals were to us in many ways, especially in our common human desire to care for the vulnerable,” she said.
“I can imagine this child was loved and cared for just like any other child.”
