Their prediction for diffuse light matched the model painted like Psittacosaurus.
The microbodies in those fossils look just like the ones in Psittacosaurus, he says.
Caption: Psittacosaurus (model shown) was a parrot-beaked herbivore about the size of a large dog.
Caption: In a slab of volcanic rock lies the complete skeleton of Psittacosaurus, with black-speckled skin.
Psittacosaurus, meaning "parrot lizard," is one of the most thoroughly studied dinosaurs, with hundreds of individual fossils.
A fossil of Psittacosaurus a little dinosaur with a parrot-like beak and bristles on its tail that roamed thick forests in China about 120 million years ago
Psittacosaurus is the third dinosaur to have its colour deduced using fossilised organelles called melanosomes that synthesise and store the pigment melanin in vertebrate animals and are present in hair, feathers and skin.
Originally discovered in 1923, 15 species have been classified as Psittacosaurus, though a recent analysis confirmed only nine of these as definite members of the genus.
Paleontologists have discovered Psittacosaurus fossils in Mongolia, China and Russia and possibly in Thailand.
Dr Zhao said that "some of the bones from baby Psittacosaurus were only a few millimetres across, so I had to handle them extremely carefully to be able to make useful bone sections.
Having four-legged babies and juveniles suggests that at some time in their ancestry, both juveniles and adults were also four-legged, and Psittacosaurus and dinosaurs in general became secondarily bipedal.
(SIT-uh-ko-SAWR-us: parrot lizard) lived 135,000,000 years ago, standing two feet high and four feet long.