Chinese Discover Oldest Belly Button

Paleontologists have discovered the oldest known belly button. Using high-tech imaging to examine the remains of a bipedal horned dinosaur of the genus Psittacosaurus, the scientists noticed the thin trace of an umbilical scar in the 125-million-year-old fossilized skin.

The researchers at the Chinese University of Hong Kong used Laser-Stimulated Fluorescence to gaze deeply into the belly of this beast, whose remains were unearthed in China two decades ago.

“Using LSF imaging, we identified distinctive scales that surrounded a long umbilical scar in the Psittacosaurus specimen, similar to certain living lizards and crocodiles,” Michael Pittman, assistant professor of CUHK’s School of Life Sciences and co-author of the study, said in a statement. “We call this kind of scar a belly button, and it is smaller in humans. This specimen is the first dinosaur fossil to preserve a belly button, which is due to its exceptional state of preservation.”

Dinosaurs did not have umbilical cords because they come into the world via eggs, with the yolk sac attached to their bodies through a slit-like opening. When dinos hatched the opening sealed up, leaving a distinctive  umbilical scar. Scientists have long assumed dinosaurs had such belly buttons and this study is the first to show fossil evidence of the fact.

Psittacosaurus grew to be a little over six feet long and moved about on two legs. The name is derived from the Latin psittac, meaning parrot, because the front of the skull is shaped like a parrot’s beak.
The findings were published in the journal BMC Biology.

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