What You Should Know About Dinosaurs

Kulindadromeus zabaikalicus was named and described in 2014. This small, only 1 meter long dinosaur was found in Siberia, and it is the first known plant-eating dinosaur with feathers and scales.

So, did most, if not all, dinosaurs have feathers?

We've already known that the majority of Theropods, flesh-eating dinosaurs including the direct ancestors of birds, had feathers or, to be more precise, feather-like structures called proto-feathers, at least on parts of their bodies or during their early life.

Now it looks like other groups of dinosaurs had feathers too - K. zabaikalicus is a basal Neornithischian not a Theropod. The oldest known dinosaur to have protofeathers.

"Developmental experiments in modern chickens suggest that avian scales are aborted feathers, an idea that explains why birds have scaly legs. The astonishing discovery is that the molecular mechanisms needed for this switch might have been so clearly related to the appearance of the first feathers in the earliest dinosaurs," said Professor Danielle Dhouailly, who studied the feathers.

Feathers evolved for the purpose of thermo-regulation and signalling, and during evolution they were co-opted for flight. In evolutionary biology, we call this exaptation - when a feature that evolved to serve a particular function comes to serve another.

Scientists from the Natural History Museum in London, the Royal Ontario Museum in Toronto and a researcher at Uppsala University in Sweden did a survey of exceptionally well preserved dinosaur fossils (75 species) from around the world after the study about K. zabaikalicus was published.

By putting together a family tree of dinosaurs and working with a statistical model to determine the chances of all these different dinosaurs having feathers, they concluded that scales, not feathers, were the norm for dinosaurs after all. The first dinosaurs were probably not feathered, but proto-feathers later evolved in dinosaurs more than just once. One of the authors, Nicolás E. Campione said, however, that the story may change. And it seems that it has: a 2020 study suggests that proto-feathers were widespread in the entire dinosaur clade.

Let's hope that the next Jurassic Park gets it right.

Scientific name:	Kulindadromeus zabaikalicus
Phylum:	Chordata
Clade:	Dinosauria
Order:	Ornithischia
Clade:	Neornithischia
Scientific reading: