The Colour of the Dinosaurs

Believe it or not, not all dinosaurs looked like they belonged in the swamp.

In all likelihood, you probably already knew this. You probably know that Raptors likely hunted in packs, or that some dinosaurs were excellent parents, or even that Tyrannosaurus rex may have been covered in feathers. What you may not know is that, in recent years, the colouration of some dinosaur species has become known to science. The notion that paleontologists could find the colours of dinosaurs, a notion once thought impossible, is now a reality.

“But Max,” I can hear you saying through your screen; “Dinosaurs have been dead for millions of years. How could we possibly know what colours they were?” It goes without saying that we can’t exactly use the eye test because, you know, fossils aren’t exactly known for their vibrancy (though there are some exceptions). Instead, paleontologists have had to look at the genetics of colouration in living dinosaurs to decipher that of their ancestors. By living dinosaurs, I of course mean the birds.

The eccentric colouration of bird feathers comes from the expression of the pigment melanin. Bird feathers contain four variations of melanin, each of which codes for different sets of colours: one for black, brown and grey colours, one for ginger tones, one for red and pink and one for purple and green. The colour of mammalian hair also stems from the presence of melanin, though mammals lack the variants that code for red and pink, and green and purple. Since the same variations code for the same colours in mammals and birds, it is safe to say that the colours they code for are universal.

So…how exactly does that help us? Luckily for paleontologists, melanin is a resistant chemical that can withstand extreme conditions, including heat and compression. In other words: it can survive fossilization. This was confirmed by paleontologists who, using high-powered microscopes, discovered their presence in the form of melanosomes (melanin carriers) within the feathers of theropod dinosaur fossils. After comparing the melanosomes of the fossilized dinosaurs to that of birds, paleontologists have revealed an array of truly vibrant colour schemes and patterns.

The first, and perhaps most striking, dinosaur examined was the theropod Sinosauropteryx. Studies on the melanosomes have revealed primarily ginger feathers with a striped tail reminiscent of a Lemur. Other notable feathered dinosaurs include the infamous Microraptor, whose feathers had a colour scheme of blue and iridescent black; Anchiornis, which had black and white wings with a red crest; and Caihong, which sported multiple colours across its head, making it a “rainbow dinosaur” of sorts. The wide variations of colours are likely the result of sexual selection and the differentiation of species. With so many different species of small, feathered dinosaurs, it would have been important to have vibrant and distinct colours, so as to not confuse your mate with an entirely different species. Talk about awkward…

The known colour of dinosaurs isn’t just restricted to feathered dinosaurs either. The nodosaurid Borealopelta, famous for its near-perfect skin impressions, was revealed to have skin comprised of red and brown on its back and white on its underbelly. This colouration is known as countershading and would have helped Borealopelta camouflage seamlessly into its environment.

Will the colours of all dinosaurs be revealed one day? Probably not. In order for melanin to be identified, the structures of the body that contain melanin – the feathers and skin – must be present on the fossil. Both are extremely rare in the fossil record, meaning that for the majority of dinosaurs, identifying colouration will be impossible to begin with. Additionally, fossils must be in excellent condition for melanosomes to be preserved. Sinosauropteryx and Borealopelta are two of the most well-preserved dinosaur fossils known, while Microraptor and Anchiornis are respectively known from dozens and hundreds of well-preserved remains. Most dinosaurs aren’t so lucky, meaning that their colours may never be revealed.

Having said this, the advancement of technology within the field of paleontology may soon help to nullify this issue. Dinosaurs with fossilized skin impressions – such as Edmontosaurus, Triceratops and even Tyrannosaurus – may soon have their appearance revealed.

Let’s hope for a tiger-skinned T-rex, however unlikely that may be.

Works Cited

I do not take credit for any image found in this article.

Header image of Microraptor takeoff courtesy of Emily Willoughby, whose work can be found at her website: https://emilywilloughby.com/art

Caihong courtesy of Lucas Attwell, found here

Sinosauropteryx courtesy of Joanna Kobierska, found here

Borealopelta courtesy of Julius Csotonyi, found here

Anchiornis courtesy of unknown, found here

1. Benton, M. J. Dinosaurs Rediscovered: the Scientific Revolution in Paleontology. Thames & Hudson, 2020.
2. Black, Riley. “Microraptor Was a Glossy Dinosaur.” Smithsonian.com, Smithsonian Institution, 9 Mar. 2012, www.smithsonianmag.com/science-nature/microraptor-was-a-glossy-dinosaur-119691559/#:~:text=Microraptor%20feathers%20were%20iridescent%20blue,quite%20fashionable%20among%20feathered%20dinosaurs. 
3. Greshko, Michael. “It’s Official: Stunning Fossil Is a New Dinosaur Species.” Science, National Geographic, 10 Feb. 2021, www.nationalgeographic.com/science/article/nodosaur-dinosaur-fossil-study-borealopelta-coloration-science. 
4. Greshko, Michael. “New ‘Rainbow’ Dinosaur May Have Sparkled Like a Hummingbird.” Animals, National Geographic, 10 Feb. 2021, www.nationalgeographic.com/animals/article/new-dinosaur-rainbow-feathers-china-caihong-paleontology-science.