The dinosaur with the oldest “navel” to which egg yolk sacs were attached has been discovered in 125-million-year-old fossils from China.
- Paleontologists have set a record for the oldest navel ever found in reptiles and mammals.
- Researchers use laser imaging technology to reveal details
- Two decades ago, a 125-million-year-old fossil was found in China.
The oldest navel was discovered by paleontologists on a 125-million-year-old bipedal fossil. China.
A barely noticeable mark on the navel belongs to the genus of reptiles psittacosaurus who lived in the Cretaceous period.
The researchers note that dinosaurs did not have an umbilical cord, unlike humans, because they laid eggs.
3D reconstruction of a recumbent Psittacosaurus showing a long umbilical scar surrounded by characteristic scales, which was identified by the research team.
Instead, the yolk sac of dinosaurs was directly attached to the body through a slit-like opening, which is also found in other land animals that lay eggs.
It was this hole that closed around the time the animal hatched, leaving a distinctive long umbilical scar.
While the egg-laying nature of dinosaurs predicts a long navel scar, this study is the first to support this hypothesis with fossil evidence.
Scientists saw the markings when they exposed the fossil to a specific beam of laser light.
“This Psittacosaurus specimen is probably the most important fossil we have for dinosaur skin studies,” vertebrate paleontologist Phil Bell, senior lecturer in the University of New England’s School of Environmental and Rural Sciences in Armidale, Australia, said in his study. statement.
“But it continues to bring surprises that we can bring to life with new technologies such as laser imaging.”
Laser stimulated fluorescence (LSF) image of an entire Psittacosaurus specimen showing the location of the umbilical scar. The insets show a close-up of the umbilical scar, including the characteristic scales surrounding it (highlighted in blue in the line art).
The results were published in the international journal of biology. BMK Biology.
Using LSF imaging, we identified distinctive scales surrounding the long umbilical scar in the specimen, similar to some living lizards and crocodiles. We call such a scar a navel, and in humans it is smaller, the doctor said. Michael Pittman, Associate Professor, School of Chinese University School of Life Sciences Hong Kong.
“This specimen is the first dinosaur fossil to have preserved a navel due to its exceptional preservation.”
The early Cretaceous horned dinosaur Psittacosaurus was discovered in northeast China and is a distant relative of Triceratops.
This well-preserved fossil was announced last year as the first discovered dinosaur anal hole.
“The anatomy is unique,” lead researcher Jacob Winter, a paleobiologist at the University of Bristol in the United Kingdom, told Live Science. This is not exactly like the discovery in birds, the closest living relatives of dinosaurs. “It’s its own cesspool, shaped in a completely unique way,” Winter said.
A specimen is on display at the Senckenberg Museum in Frankfurt, Germany.