Neanderthal babies were apparently bigger — and grew faster — than familiar human tykes.

At least, El Pais reports, that’s the conclusion from a team of scientists based in Israel and Europe who analyzed the remains of a six-month-old Neanderthal ankle biter who was downright colossal, at a comparable size to a one-year-old homo sapien.

That means the babies of Neanderthals, extinct cousins to us contemporary humans, were real life versions of the distinctly sturdy cave baby Bamm-Bamm Rubble from the iconic animated show “The Flintstones”

The scientists noticed that while the skeletal remains of the Neanderthal child, buried in a cave in Northern Israel about 51,000 to 56,000 years ago, sported relatively thick bones and a large skull that made it seem older, the development of its teeth betrayed its younger age, as detailed in a new paper in the journal Current Biology.

“I believe that the histological age of the teeth is more accurate than age measured by the volume of the long bones or the endocranial cavity for estimating such a young age,” Ella Been, Tel Aviv University professor in anatomy and anthropology and the paper’s first author, told El Pais.

Previous research in 2022 also found that Neanderthal kids had more robust bones than that of modern human children; fully mature specimens of Neanderthals are typically stockier and shorter than us human adults.

“When compared with other known Neanderthal infants, the same pattern emerges: faster body and brain growth, suggesting greater energy expenditure,” Been told El Pais. “Understanding this pattern is crucial to understanding who Neanderthals were and how they adapted to their environment.”

The baby Been studied was found in a cave along with about 20 other deceased Neanderthals back in the 1960s, but scientists only started studying the remains in the 1990s. This new paper is the first comprehensive study of the child’s 111 recovered bones, according to El Pais.

This finding not only reveals more information on the development of Neanderthals, who remain mysterious, but it also throws in high relief the differences between them and us; Neanderthals lived in Europe and Asia between 400,000 to 40,000 years ago, back when conditions were harsher than they are today, and hence they went through a process of natural selection that seemingly favored the survival of robust, well-built children that could mature quickly.

Even with these differences, that didn’t stop our ancestors from getting to know each other — because there’s evidence that male Neanderthals and female humans mated and produced offspring. Signs of these intimate relations are scattered throughout our DNA, telling an ancient story of when two hominid species coexisted during prehistory.

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