CUHK belly boffins right on the button

Chinese University scientists have latched on to the oldest belly button ever found in reptiles and mammals.

The scientists and others around the world used a high-tech laser imaging technology to reveal the finest details of a 125-million-year-old dinosaur fossil found in China 20 years ago.

Unlike humans, dinosaurs did not have an umbilical cord because they laid eggs. But the yolk sac of dinosaurs was directly attached to the body via a slit-like opening - a feature also found in other egg-laying land animals.

This opening seals up at about the time the animal hatches, leaving a distinctive long umbilical scar. While the egg-laying nature of dinosaurs predicts a long belly button scar, this study is the first to support the hypothesis with fossil evidence.

The specimen is now on display at the Senckenberg Museum in Frankfurt, Germany.