17 January, 2018
A newly-discovered bird-like dinosaur fossil from China offers evidence that could add a new accessory to the list of unbelievable dinosaur adornments: a shaggy ruff of bright rainbow feathers. The feathered theropod featured an iridescent, rainbow coloured ring of feathers around its neck, which scientists believe it used to attract mates. The researchers say the rest of the family had triangular skulls and longer forearm bones than birds today.
That's because color isn't only determined by pigment, but by the structure of the melanosomes containing that pigment. Dongyu Hu, a professor in the College of Paleontology at the Shenyang Normal University, led the study.
Those nanostructures called melanosomes explain how the creature came to possess such festive plumage.
It's been called Caihong juji, which is the mandarin word for "rainbow with the big crest". While birds use asymmetrical feathers on their wingtips to help steer while in flight, it's fairly certain that Caihong juji used its plumage to attract mates and keep warm, not take to the skies, making the placement of the feathers unusual.
Co-author of the study Xing Xu, a paleontologist at the Chinese Academy of Sciences informed that the Caihong juji lived in forests and might have glided from tree to tree, preying on small lizards as well as mammals.More news: Storm causing airline cancellations, flight suspensions
The slab of rock from China's Hebei Province where the dinosaur was discovered by a farmer in 2014 contained a almost complete skeleton surrounded by impressions made by feathers. "The pigment in the feathers is black, but the shapes of the melanosomes that produce that pigment are what make the colors in hummingbird feathers that we see", explains Eliason. The researchers were unable to exactly match Caihong's colors but are confident it had an iridescent glimmer, Greshko writes.
However, unlike birds today, Caihong's asymmetrical feathers were on its tail, not its wings - a finding that suggests that early birds may have had a different steering or flight style. Scientists also found asymmetrical feathers on its tail. The Caihong had many bird characteristics but scientists say it was unlikely to have gotten off the ground.
"The tail feathers are asymmetrical but wing feathers are not, a weird feature previously unknown among dinosaurs including birds", said Xu. "This suggests that controlling [flight] might have first evolved with tail feathers". While its distinctive feathers were a relatively recent evolution, it had several traits typical of much earlier dinosaurs, including a bony crest on its head.
Asked what someone might say upon seeing Caihong, University of Texas paleontologist Dr Julia Clarke said, '"Wow!" (C. juji is thought to be the earliest known example of this melanosome shape.) The dinosaur's melanosomes were arranged differently than a penguin's, so the researchers settled on screeching neon over somber black. "It has a velociraptor-type skull on the body of this very avian, fully feathered, fluffy kind of form".