‘RAINBOW DINOSAUR’ MAY HAVE HAD GLITTERY FEATHERS
Just call it the disco dinosaur. Caihong juji, a newly discovered duck- sized dinosaur that lived around 160 million years ago in what is now China, had a vibrant rainbow crest and iridescent hummingbird-like plumage, a team of international researchers say.
The finding was made following the analysis of an immaculately preserved C. juji fossil – a name meaning ‘rainbow with big crest’ in Mandarin – first discovered by a farmer in northeastern China in 2014. The feathers on the fossil are so well preserved that the researchers were able to determine their minute colour-bearing structures.
“When you look at the fossil record, you normally only see hard parts like bone, but every once in a while, soft parts like feathers are preserved, and you get a glimpse into the past,” said Chad Eliason, who took part in the research. “The preservation of this dinosaur is incredible, we were really excited when we realised the level of detail we were able to see on the feathers.”
By examining the feathers using powerful microscopes, the researchers were able to make out the imprints of melanosomes, which are the parts of cells that contain colour pigments. While there was very little of the pigment itself present, the shape of the melanosomes alone was enough for the scientists to determine the colour of the feathers. This is because melanosomes reflect light in different colours depending on their shape. It turns out that the pancake-shaped melanosomes in C. juji most closely match those of modern hummingbirds.
Colourful plumage is frequently used by birds to attract mates, so the rainbow feathers of C.juji may well have been a prehistoric version of a peacock’s iridescent tail, the researchers say.