Ancient fossils — of both humans and animals — are more common in limestone than people may think.
Kidipadeli75/RedditThe human mandible even appears to still contain some teeth.
When a couple in Europe renovated their home, they chose to tile their floors with a popular limestone called travertine. But then their dentist son visited and noticed something strange: the unmistakable shape of a human jawbone sitting in the freshly laid stone.
He posted a photo of the mandible on Reddit, where the odd find has drawn fascination — and plenty of questions.
‘Could It Be A Hominid?
In April 2024, Reddit user Kidipadeli75 posted a picture on Reddit of what he suspected was a human mandible pressed into his parents’ new floors.
“My parents just got their home renovated with [travertine] stone,” he wrote. “This looks like a section of mandible. Could it be a hominid? Is it usual?”
Kidipadeli75’s guess was an educated one. As the Reddit user told the Washington Post — he’s stayed anonymous to protect his family’s privacy — he recognized the jawbone from his work as a dentist.
Kidipadeli75/RedditThe mandible with a banana to give it a sense of scale.
“It’s not so much the teeth that I noticed but the shape of the mandible that is very recognizable,” he explained, noting that the mandible looks like images taken with CT scans in dentistry. “As I am specialized in implant dentistry I work with this kind of image everyday and it looked very familiar.”
So how did the human mandible end up in his parents’ limestone floor?
How Fossils End Up In Travertine
Fortunately, the human jawbone found in travertine is most likely more than a million years old — and not from a recent murder victim.
“Travertine is a limestone that forms near natural springs,” John Hawks, a University of Wisconsin paleoanthropologist, explained in a post entitled How many bathrooms have Neanderthals in the tile? “When the water evaporates or cools — especially near hot springs — this calcium carbonate precipitates as rock and may form very large deposits around the spring.”
Ustill/Wikimedia CommonsTravertine is a popular limestone both because it comes in a variety of colors and because of its versatility.
Hawks continued: “Travertine also commonly includes fossils. Many are fossil inclusions of algae, plants, and small animals — especially molluscs and crustaceans — that live within the spring water. Much larger animals may be found and humans are no exceptions: Several well-known hominin fossil discoveries are from travertine deposits.”
The tile with the jawbone came from the Denizli Basin in western Turkey. Researchers have determined that the stone within this quarry was formed between 0.7 million and 1.8 million years ago. And, in fact, several fossils have previously been discovered there.
Not only have the fossils of mammoths, rhinos, giraffes, horses, deer, reptiles, and turtles been found in Denizli Basin travertine, but human fossils have been found, too. In 2002, workers came across a human skull while cutting limestone. Researchers determined that the bone belonged to the first specimen of Homo erectus to ever be discovered in Turkey.
Erturac/Wikimedia CommonsThis skull fragment belonged to a specimen of Homo erectus that researchers dubbed the Kocabaş hominin.
And as Hawks noted, such pieces of bone in tile are more common than people may think. Though he recommends getting in touch with the local authorities if you suspect there’s “an ancient human… looking back at you,” such fossils are not necessarily all worth excavation and examination.
“Believe me, anthropologists don’t want to hear about every blob of bone in your tile,” he wrote. “Bones from other kinds of animals massively outnumber hominin bones in large travertine deposits… Nobody wants to drill into your shower wall on a wild goose chase.”
After reading about the human mandible discovered in a European couple’s new travertine floors, discover the misunderstood story of Neanderthals, the hominin species that went extinct 40,000 years ago. Or, read about the Callao Man, the hobbit-like human early ancestor.
