A squad of extinct con artists has emerged
Animals are deceitful; they’re the greatest tricksters of all time, more adroit than any of the tricksters like Harry Houdini or David Copperfield. Chameleons, antelopes, Polar Bears, Ornate Wobbegongs* are a few examples of this great squad that performs trickery to deceive their deadly predators. In the scientific notation, the trickery performed by these animals is known as camouflage. Camouflage, a.k.a cryptic coloration, is an adaptation that allows animals to blend in with certain aspects of their environment. Hence, increases an organism’s chances of survival. Now is the time we are aware of the fact that gigantic animals like dinosaurs have been observed to have performed the act of camouflage. Only after the discovery of the well-preserved fossil of Borealopelta markmitchelli, a tank sized dinosaur, it was concluded that even the dinosaurs had to hide from their carnivorous predators. (Guglielmi,2017)
Borealopelta m., a nodosaur, used to play hide and seek on Western Canadian lands about 110-million-years ago by blending itself with the surroundings. After its 5.5-meter specimen was unearthed from the Canadian mines in Alberta, paleontologists concluded it to have performed countershading, a form of camouflage where the part of body fronting the sky is dark in color whereas the part of the body that is fronting the ground is light in color. Modern animals like antelopes, penguins, and sharks observed to have performed countershading to hide from their predators.
Molecular Paleobiologist from the University of Bristol state, Jakob Vinther states that Borealopelta m. had dense armor on its back, tail, neck, as well as, its face. Despite this great adaptation, this plant-eater, Borealopelta m. needed significant protection from its meat-eating predators. (Davis 2017)
The accidental discovery of Borealopelta m. the fossil was a breakthrough moment in the history of dinosaur coloration. Through the help of fossils, researchers were able to tell about the darkish-red pigmentation on the surface of its body. (Guglielmi, 2017) This was an awestruck discovery for the researchers, never before a dinosaur was observed to have been reddish in color.
Researchers later concluded that the darkish-red color on the body of Borealopelta m. is due to the accumulation of melanin, a natural pigment present in the body, which has the capability to scatter the damaging ultraviolet radiation directly from the sun. Melanin is synthesized, stored, and transported by tiny organelles called Melanosomes in Melanocytes, the melanin-producing cells. There are two types of melanin found in animals' bodies pheomelanin, which is dark red in color, and eumelanin, which is brown in color. Borealopelta m. had pheomelanin in its body, which is why it had a dark red back.
“We could see that the organic compounds [in the film] were something that contained carbon, nitrogen, and sulfur — that is something that we know is typical for [the pigment] red melanin,”
-Vinther. (Davis 2017)
The ability to camouflage develops when the conditions became life-threatening for an animal to thrive. When the stress that Borealopelta m. has been experiencing with being eaten by its predators on a regular basis, the species evolved the ability to camouflage, especially countershading. Countershading was an ideal form of camouflage for Borealopelta m. because of its size compared to other dinosaurs like Tyrannosaurus rex, Albertosaurus, Dilophosaurus, Spinosaurus, and other deadly meat-eating theropods. Countershading depends on the three-way interaction between object shape, the quality of light, and the location of the viewer. It contributes to visual camouflage. This kind of adaptation must have helped Borealopelta m. to blend in with the surroundings when approached by a taller predator. For example, when the predator, a theropod, looks down in search of its prey, Borealopelta m., it will be tricked by the reddish-dark color on the back of Borealopelta m. matching the reddish-dark color ground. Being tricked by its prey, the theropod will not proceed eating its prey.
The fossil of Borealopelta m. is thought to have been drowned in the river and fallen on the seafloor, but the remnants of the dinosaur were so well preserved that researchers were able to retain preserved skin from the fossil to observe the pigmentation. Now the magnificently preserved fossil of Borealopelta markmitchelli is now showcased in the Royal Tyrrell Museum of Paleontology in Alberta and is been considered the best-preserved armored dinosaur in the world (Davis 2017).
“There is always so much hyperbole when a new dinosaur is discovered, but this one deserves all of the superlatives. It is one of the most gorgeous, best-preserved skeletons I’ve ever seen,”
-Stephen Brusatte, a paleontologist at the University of Edinburgh
Another dinosaur, known as Psittacosaurus had a parrot-like beak and bristles on its tail, also have been found to have performed countershading. It is believed to have roamed in the thick forests in China about 120 million years ago. Psittacosaurus was also under threat of being eaten by theropods. However, this species didn’t have any armor on its body to protect itself, which is why it adapted camouflage. Along with bipedal, this 1.5-meter dinosaur used its distinctive beaks to nibble through the vegetation of the Cretaceous.
Researchers, while studying its fossil found the melanosomes in the remnants like soft tissues, feathers, fur, and skin, which again proves the fact of the darkish color on the skin. They used scientific techniques to see the pigments in the dinosaur; they fired a laser at the specimen to see the remnants on the animals' scales. But only after using an electron microscope, they confirmed the presence of melanosomes in the skin of Psittacosaurus. (Panciroli)
The fossil of Psittacosaurus has so well persevered that we can observe its cloaca, the multi-purpose opening for excretion, reproduction, and urination. Moreover, the look of the dinosaur is compared to that of a parrot, which is why it is considered as “parrot-like” by many of the researchers. It had a beak-shaped face and believed to have the same muscle arrangement as a parrot. (Panciroli)
Psittacosaurus’s fossil has been preserved in a Lagerstätte*, which is a form of the sedimentary deposit that preserves fossils exceptionally well through the years.
Although animals widely perform camouflaging techniques to protect themselves from their predators, sometimes they perform it to attract mates, regulate body temperature, or just to give off warning signals.
Seeing the depictions of dinosaurs in blockbuster movies like the Jurassic Park series, we always have thought dinosaurs to be the dominant terrestrial vertebrates, yet we were unaware of the small plant-eating dinosaurs like Borealopelta m. and Psittacosaurus, who were struggling to survive every day. Living in the Cretaceous period was hard for both Borealopelta m. and Psittacosaurus, but due to their evolved ability, they were able to survive those deadly years and dangerous theropods. In order to survive, they followed the Theory of Evolution by Natural Selection, which was proposed by English biologist, Charles Darwin, which states that the chances of survival of a species increase if it inherits changes according to the surrounding. In other words, it means the heritable change in the specific population over time, as the population experience stress from the surroundings.
These new discoveries have opened up fresh pathways for science, especially paleontological science. Now, we will be able to tell more about the pigmentation present in the dinosaurs, which was a complex and controversial topic among many paleontologists. We also became aware of the fact that dinosaurs performed camouflage to fool its predators in the environment it lived. This could mean the “Cretaceous is bloody scary” says Jakob Vinther. Through these discoveries over the past few decades, we will be able to make more predictions about these extinct creature’s environment and traits, as well as the Cretaceous period.
References:
- Giorgia Guglielmi (2017) “Did this big dino use camouflage to hide from predators?” Science Magazine, Web. 3 August 2017.
- Nicola Davis (2017) “Heavily armored dinosaur had ginger camouflage to deter predators”, The Guardian, Web. 27 November 2017.
- Traci Watson (2016) “Did this big dino use camouflage to hide from predators?” National Geographic News, Web.14 September 2016.
- News Staff (2017) “Meet Borealopelta markmitchelli, ‘Best-Preserved Armored Dinosaur” Sci-News, Web. 3 August 2017.
- Will Dunham (2017) “Scientists decipher color of ‘super cute’ bristly dinosaur” Reuters, Web. 15 September 2016.
- Elsa Panciroli (2016) “Scientists reveal a most accurate depiction of a dinosaur ever created”, The Guardian, Web. 14 September 2016.
- Rachel Becker (2017) “This massive, spiky dinosaur might have used camouflage to fool predators”, The Verge, Web. 3 August 2017.
- Jacqueline Ronson (2017) “This Guy Spent 7,000 Hours Chiseling a Dinosaur From its Tomb”, Inverse, Web. 3 August 2017.
- A reconstruction of Borealopelta markmitchelli. Image credit: Royal Tyrrell Museum. Sci-News, Web. 3 August 2017.
- Robert Clark (2017), Digital Image, National Geographic, Web. 3 August 2017.
- Natural selection, Image, University of California Museum of Paleontology, Web.
- Psittacosaurus, Digital Image, Senckenberg, Web.
