In recent years, Neanderthals have started to look a lot more human. Not only have researchers unraveled their DNA, finding that many modern humans carry some Neanderthal genes, but paleoarchaeologists have also found evidence that our evolutionary cousins walked upright, had brains larger than ours, enjoyed greater lung capacity and may have communicated with a complex language. Homo neanderthalensis also had a complex culture that included burying their dead, and making tools, sticky pitch, clothing, jewelry and perhaps even art.

Despite these discoveries, skeletal remains and spearheads can’t tell us everything, like what Neanderthal family structures looked like. But a remarkable find of 257 Neanderthal footprints along the coast of Normandy, France, is revealing a little bit about the the groups the species lived in. Ivan Couronee at Agence France-Presse reports that the site, called Le Rozel, was first discovered by an amateur archaeologist in the 1960s. However, it wasn’t until wind and tidal erosion in the area threatened the site in 2012 that consistent excavations at Le Rozel began. Between 2012 and 2017, the researchers excavated 30 feet of sand to uncover 257 footprints dating back 80,000 years, detailed recently in the Proceedings of the National Academy of Sciences. Since 2017, the team has discovered hundreds of other footprints.

Among the impressions, the team also found materials associated with animal butchering and stone tool production. While there are no skeletal remains at the site to confirm that the prints were made by the pitter-patter of Neanderthal feet, the researchers are pretty sure they were left by the species based on the shape of the foot, which differs from modern humans. At that time, researchers believe, Neanderthals were the only hominin species in Europe. Anatomically modern humans would not arrive on the continent for another 35,000 years.

While footprints were found in five layers of sediment, reports Alison George at New Scientist, 80 percent of them appeared in a 1,000-square-foot section in just one layer, which the study focuses on. The team photographed and modeled each print. They also used a material called elastomer to make casts of several of the footprints. Based on the size of the feet, they could estimate the height of the Neanderthal that made them. From that they could estimate each individual's age.

Of the 257 footprints, 90 percent were made by children, ranging from two years old to adolescents. In total, the team believes about 10 to 13 people left prints at the site. The fossils were created after the Neanderthals stepped in mud, which then dried and was covered by sand, as the area was part of dune system at the time.

“It’s difficult to figure out why those individuals were there at that particular time: Were they looking for food or playing or doing something else?” Isabelle de Groote of Liverpool John Moores University, not involved in the study, tells New Scientist. “I would expect either more adults or more of a balance between the number of adults and young people.”

At least one set of adult prints does appear at the site, and it overturns some conceptions about Neanderthals. In general, Neanderthal skeletons show that they were relatively short, ranging between 4’9” to 5’2.” However, extrapolating from the size of the footprints, the team found the adult would have been around 5’8,” close to the average height for men in the United States today, or even taller. It’s possible that this particular Neanderthal was unusually tall. It’s also possible that researchers were previously mistaken about the average height of the species.

The prints offer a different insight into Neanderthal lives than other sites, which may have been occupied for years or even hundreds of years. “They record a kind of snapshot into the lives of individuals over a very short period,” says co-author Jeremy Duveau, a doctoral student at France's National Museum of Natural History. “That gives us some insight into the composition of the group, but it is possible that it represents only those members of the group who happened to be outside at the time.”

Whatever the case, the hundreds of prints represent a unique opportunity to study Neanderthal life, considering prior to this study only nine Neanderthal prints had been found, spread out between Greece, Romania and France. Earlier this year, one footprint from a young Neanderthal was discovered in the dunes around Catalan Bay in Gibraltar.

Despite lasting 80,000 years, the prints at Le Rozel aren’t long for this world. Duveau reports that the researchers were able to conserve and lift some of the prints from the beach using a new chemical technique. However, those that they could not extract were obliterated by the strong winds off the English Channel.