A 125-million-year-old dinosaur fossil has the oldest belly button known to science

Paleontologists have discovered the oldest known belly button on a 125-million-year-old fossil of a Psittacosaurus dinosaur. Oh, the fossil also had the first dinosaur asshole ever found.

As reported by Live Science, the psittacosaurus lived between 145 and 66 million years ago during the Cretaceous Period, and scientists discovered this belly button after exposing the fossil to a concentrated beam of laser light.

Artist's rendering of the Psittacosaurus.  Photo credit: Jagged Fang Designs

Artist’s rendering of the Psittacosaurus. Photo credit: Jagged Fang Designs

These scientists reported their findings June 7 in the journal BMC Biology and said they spotted a “thin trace of an umbilical scar” that represents a “slight misalignment in the skin pattern and scaled across the dinosaur’s abdomen and was the reptilian equivalent of a.” mammalian belly button.”

While fetal mammals get their nutrients from a placenta, birds and reptiles get their nutrients from a yolk sac connected to their abdomen by blood vessels. When these types of creatures hatch, the yolk is absorbed by the body, leaving only an abdominal scar.

In most birds and reptiles, the scar will heal in a few days or weeks, but some reptiles, including alligators, can have the scar “beyond sexual maturity.” This fossil has shed new light on dinosaurs and gives an indication that some dinosaurs had these scars that didn’t heal early.

The fossil, known as SMF R 4970, was an early species of ceratopsian named Psittacosaurus mongoliensis, which fell into a group of beaked herbivores that includes Triceratops. Discovered about 20 years ago, it was so well preserved because the dinosaur was “petrified lying on its back.” This also led to scientists discovering the aforementioned “perfect” and “unique” asshole.

“Using LSF imaging, we identified distinctive scales surrounding a long umbilical scar in the Psittacosaurus specimen, similar to [scars in] certain live lizards and crocodiles,” said paleontologist Michael Pittman, an assistant professor in the School of Life Sciences at the Chinese University of Hong Kong, in the statement. “We call this type of scar a belly button, and it’s smaller in humans . This specimen is the first dinosaur fossil to be given a belly button, owing to its exceptional state of preservation.”

Aside from its importance to science, this fossil has also been the subject of “a lot of controversy about its origin”. Discovered in the 1980s or 1990s in an undisclosed region of China, the fossil was “allegedly smuggled out of the country and into underground European markets before being purchased and displayed at the Senckenberg Museum in Frankfurt, Germany in 2001.”

“There is an ongoing debate over the legal ownership of this specimen and efforts to repatriate it to China have been unsuccessful. Our international team of Australian, Belgian, British, Chinese and American members all hope and support an amicable resolution to this ongoing debate,” the researchers write in their paper. “We think it is important to note that the specimen was acquired by the Senckenberg Museum to prevent it from being sold into private hands and to ensure its availability for scientific study.”

To learn more about dinosaurs, read how the Tyrannosaurus Rex may have actually been three different dinosaurs, and the dinos recently discovered in England that have been dubbed the “Hell Heron” and “Riverbank Hunter.”

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Adam Bankhurst is a news writer for IGN. You can follow him on Twitter @AdamBankhurst and further Pull out.