Since no one has ever seen a living dinosaur, how did dinosaurs get their colors?

In the 1990s, the movie "Jurassic Park" and the documentary series "Walking with Dinosaurs" used computer modeling technology for the first time to bring living dinosaurs to the big screen, allowing fans around the world to see the charm of these animals.

The image of Tyrannosaurus Rex in Jurassic Park (1993)

Poster for the 1999 BBC documentary Walking with Dinosaurs

Today, with the advancement of technology, we can also see more and better paleontological documentaries. However, with the popularity of the film and the spread of paleontological culture, a new question soon emerged before everyone:

“How did you get the colors of these animals?”

A restored picture of the dinosaur that everyone is familiar with - Tyrannosaurus Rex. When appreciating the painter's work, have you ever thought about how the colors of the dinosaurs were matched?

Regarding this issue, there used to be a saying that "the artist can choose whatever color he likes", and this saying has been widely circulated. It has been labeled as "cold knowledge" on many platforms, but here I want to tell you that this is a fallacy. As the saying goes, adaptation is not random editing, and there are also tricks in matching colors for the restoration paintings of ancient creatures.

If you can find color evidence in fossils, that's the best. Scientists have found traces of melanosomes in the skin and feathers preserved by some creatures.

This is a kind of pigment granules in organisms. Scientists only need to study the arrangement of these pigment granules and compare it with the arrangement of pigment granules in the skin and hair of animals today to know what color the ancient organisms were when they were alive.

The molecular structures of the two melanins and the microscopic appearance of the two melanosomes observed under a microscope

The colors of feathered dinosaurs are probably what we are most familiar with. For example, in 2012, paleontologists determined that the feathers of Microraptor were mainly black, with a metallic luster on the surface, by studying the melanosomes left in the fossils of Microraptor. In other words, the color of Microraptor is similar to that of today's crows, which can be called "colorful black".

Microraptor fossil with preserved feathers

Reconstruction of Microraptor

Microraptor's coloration is similar to that of a crow

The reason for the evolution of this color may be related to the living environment of Microraptor. As a predator living in trees, when Microraptor hides in the tall dark-colored tree canopy, black can help it conceal and not be easily discovered by vigilant prey.

As for the metallic luster on the feathers, scientists originally thought it was a tool to attract the opposite sex. But in 2023, the color of the Microraptor's close relative, Wulong, was also determined. Its color is similar to that of today's gray magpie, and its feathers also have a metallic luster.

Considering that the Wulong specimen was not fully grown and not yet at the age of "looking for a partner", this metallic luster was not used to attract the opposite sex. It is now believed that this luster helped dinosaurs identify different individuals and was their unique "identity card".

The fossil of the dragon dance and its restoration

Melanosomes found in the feathers of Sinosauropteryx and Sinornithosaurus fossils

In addition to Microraptor and Wulong, the colors of other dinosaurs such as Sinosauropteryx, Anchiornis, Caudipteryx, Sinornithosaurus, and Pterosauria have also been determined. However, these dinosaurs are not big, so are there any big ones whose colors have been determined by scientists? You won’t believe it, there are some.

Reconstruction of Sinornithosaurus, whose feathers may have been reddish-brown

For example, the nodosaur Borealopelta, which lived in Canada in the early Cretaceous period, was about 5.5 meters long and weighed 1.4 tons. The fossil of this armored dinosaur presents a rare "mummy" form - not only the skin and armor are preserved, but also some of the internal organs. Scientists speculate that it sank to the bottom of the sea and was buried shortly after its death, so it is so well preserved.

By studying the melanosomes in its tiny scales, paleontologists discovered that the color of the Northern Shield Dragon was red, and the color of its back was darker than its abdomen, so it can be called a domineering "red armored vehicle."

The fossil of the northern shield dragon shows its state of preservation

A reconstruction of the Northern Shield Dragon, showing that it is red in color

In 2023, scientists found traces of melanosomes in the fossilized leg skin of a Diplodocus specimen, which led to the conclusion that the skin of the Diplodocus' legs might be ginger yellow. That is, the body color of the real Diplodocus is close to the restored image of the Diplodocus in the BBC documentary "Walking with Dinosaurs".

This is the first time scientists know the body color of sauropod dinosaurs. Its discovery may indicate that giant sauropods may have had quite a variety of colors.

The image of Diplodocus in the BBC documentary "Walking with Dinosaurs"

Dinosaurs that can discover colors are just the tip of the iceberg in the dinosaur family. What about the many more dinosaurs that have no skin or feathers?

Although there is no direct evidence, modern animals can provide us with references. We can refer to some animals with similar ecological niches today for color matching - this method was used when dinosaur research was just beginning. Paleontologists referred to today's large reptiles such as crocodiles, monitor lizards, and pythons. The body color of large herbivorous dinosaurs was restored to be mainly gray and green, while the color of large carnivorous dinosaurs was mainly gray-brown.

But today, with the advancement of dinosaur research, we know that dinosaurs were more diverse than we previously thought, and can fully refer to modern birds and mammals.

For example, when reconstructing Oviraptorosaurs, scientists will consider that they have similar lifestyles to today's cassowaries, emus, pheasants and other birds, so they will refer to their colors. When reconstructing Dromaeosaurs, they will also refer to the colors of raptors and canids because they also have similar survival strategies.

The image of Gigantoraptor (an oviraptorosaur) in the documentary "Dinosaur Revolution". It can be seen that its color scheme was based on the living tragopan

Living male red-bellied tragopan

Speaking of this, we have to mention a dinosaur restoration that is often ridiculed by everyone - the Deinocheirus in the documentary "Super World of Dinosaurs" was covered with a layer of pink feathers, so it was ridiculed by everyone as "Peppa Pig color scheme".

In fact, this restoration cannot be said to be completely nonsensical - the ecological niche of Deinocheirus may be similar to today's herbivorous waterfowl, so the documentary production team chose the color scheme of flamingos as a reference.

However, we can only blame the production team for their lack of skills, because the flamingo's color is due to the algae it filters in the salt lake, and the habit of Deinocheirus, which eats aquatic plants and occasionally fish, is obviously different from that of the flamingo. Various cranes and Anseriformes may be the best references for Deinocheirus.

The image of Deinocheirus in the documentary "Dinosaur World"

Living flamingos

Some people always say that dinosaur restoration is like a blind man touching an elephant, so there is nothing unrealistic about random color matching. However, in the story of the blind man and the elephant, the blind man who touched the elephant's tail was able to conclude that "the elephant is like a rope", which is still a reasonable speculation based on known evidence, and the same is true for dinosaur restoration.

Author: Qianxi Jun

Editor: Dong Xiaoxian

Reviewer: Liu Kun and Li Peiyuan