Paleontologist Michael Benton and Paleozoic artist Bob Nichols show what dinosaurs really looked like. For a long time they were thought of as cold reptiles, but they were actually warm-blooded and feathered in the dinosaur kingdom.
Arguably the most attractive of all dinosaurs, Tyrannosaurus Rex is still depicted as a monster with hard scaly skin. But in fact, the T. rex had plumage. Convincing evidence of this was found ten years ago. but in my tracks Jurassic Park who appeared next, the shadow of the giant scaly T. rex. The creators were afraid that the feathers would resemble a giant chicken. The T. Rex had to remain the terrifying beast.
It has been two centuries since the remains of the first dinosaurs were found in England. Scientists didn’t know what they were seeing. They thought of huge lizards or some kind of giant crocodile, until after two decades they had to conclude that this is an unknown and extinct group of earthlings. They were baptized dinosaurs, literally: large, terrifying reptiles.
The name is incorrect, dinosaurs were not reptiles, but they still existed. As well as many impressions of many types of dinosaurs. Meanwhile, the scientific picture of dinosaurs has been repeatedly, and often radically, modified over the past two centuries. No wonder, because science is able to extract more and more information from the extant remains of dinosaurs.
A revolution in dinosaur science
If an animal had access to fossils – and this chance was small – only the hard parts of its body would be preserved. Rarely, the soft parts, such as the muscles, viscera, and skin, may become ossified. So it is not easy to rebuild it. Michael Benton, the famous British paleontologist, and Bob Nichols, a British artist who paints and builds dinosaurs, now show in a beautifully executed book what we know about the emergence of many types of dinosaurs.
Their story begins with a drawing of the most recent revolution in dinosaur science: the 1969 picture of Deinonychus. The drawing is based on research by American paleontologist John Ostrom, who led the excavations of this medium-sized dinosaur. But it was created by his student Robert Packer.
Until then, dinosaurs were taken for slow bullies. Deinonychus was shown to be built for speed, with a slender and balanced body, hind legs that could accelerate, and short front legs with claws that could mortally injure prey, even if it was larger than the hunter himself.
Cold-blooded or warm-blooded
The creator of the drawing, Robert Packer, has remained an important innovator in dinosaur science ever since. He played a huge role in elucidating another myth. The myth that dinosaurs were cold-blooded animals, like reptiles.
Cold-blooded people have the advantage of not having to keep the stove burning; Their bodies keep track of the ambient temperature. Warm-blooded animals maintain their body temperature. They have the advantage that they can be more active, but they have to eat a lot for this. The elephant weighs 5 tons and eats 225 kilograms of food per day. Sauropods, dinosaurs, could be up to 100 feet (30 meters) long and weigh 50 tons, ten times that of an elephant. How much did they have to eat, 2,250 kilos?
number. The sauropod only needs the same portion as the elephant. Because he had three advantages. The first feature was the size of his body. As the body gets older, its contents grow faster than its surface. This is mathematics. A mouse has a lot of surface skin per kilogram, a baby elephant, and a Sauropod even less. A large body is relatively easier to maintain temperature than a small one. For giants, cold-blooded and warm-blooded are not that far apart.
The second feature of large dinosaurs is that they lived in a temperate climate, a world without polar ice caps and warm summers and mild winters. There was no need for much of a burner. The third and final advantage of sauropods was that they did not have to spend their energy on maternity care. Because they didn’t. They did not give birth, did not nurture, and did not raise. The sauropods laid eggs and left them behind. This did not increase the youngsters’ chances of survival, but required a little energy from the parents.
feather leather
In recent decades, it has become increasingly clear that dinosaurs were not the cold, slow reptiles they were kept for, but rather, they were warm-blooded, energetic animals. This also indicates that many types of dinosaurs had hairy skin or feathers. Evidence of this was found already in the 90s, when the remains of several small dinosaurs with a wardrobe full of feathers were discovered in China. Among them is Sinosauropteryx (see box).
It is now clear, as Michael Benton writes, that feathering occurred not only in the small dinosaurs that are the ancestors of now-living birds, but also in the large dinosaurs. Even Yutyrannus had feathers, and that dinosaur was thirty feet long.
Sinosauropteryx
Sinosauropteryx was the first feathered dinosaur found in 1996 in China. This was a sensation in the scientific world. There was already a suspicion that dinosaurs had hair and/or feathers, and now a Chinese farmer has the first clue.
The swift squaw is about 1 meter long, and lived in the early Cretaceous period, about 125 million years ago. In the image of Bob Nichols, Sinosauropteryx just got a lizard. He tosses it for a moment and then swallows it in one sitting. Sinosauropteryx did not chew his food. The book also contains pictures of the first Chinese discovery; Beautiful fossils, on which the remains of feathers and even the contents of the stomach are clearly visible, with a whole lizard.
Michael Benton describes how his research group at the University of Bristol in England was able to identify the reddish-brown color of the animal in its fossil remains. In addition, the same reddish-brown pigment can be seen around the eyes of Sinosauropteryx, giving it a thief mask. It was meant to deter enemies.
Benton wrote that the striped pattern of the tail feathers helped “to impress and decorate partners”. Also in many species of live (colored) birds the feathers have this function. The coloration of the dark back and white belly shows that Sinosauropteryx lived in an open field.
edmontosaurus
Edmontosaurus lived in the last Cretaceous period, up to 66 million years ago, when a meteorite impact ended the empire of the dinosaurs and much other life on Earth. Edmontosaurus belongs to the brontosaurs, the largest of all dinosaurs. But he was small in the family, his body was no more than twelve meters long.
Many of its ancestors were smaller, bipedal and meat-eating, such as Sinosauropteryx, which also appears in these pages. A dinosaur like Edmontosaurus was large and heavy: 4 tons, like the weight of an elephant. Walking was impossible for him. This giant did not eat meat but plants.
Many of these little ancestors had feathers, but Edmontosaurus did not; Its skin consists of small scales the size of a few millimeters. We know this is special, because when such a monster is finished, it usually gnaws at bones, skin and hair. But a few specimens of Edmontosaurus were found that were mummified due to special conditions, so that parts of the skin were preserved.
The special thing about the skin of this dinosaur is that the scales are supported not by a structure or bony plates, but by keratin, a protein that is also found in feathers and hair. Nichols tells how his research team envisioned the consequences of this fourteen years ago. Because the skin grows from the inside, the top layer must split into pieces and fall off the body. Dino had dandruff! British newspapers made headlines at the time.
This observation also has a dangerous side, because it confirms the warm-blooded nature of dinosaurs. Reptiles do not suffer from dandruff, only warm-blooded animals infect it. Cold-blooded reptiles replace their skin by shedding everything at once.
Michael J. Benton, Dinosaurs. What they really look like, with illustrations by Bob Nichols, Editor. The Nordic Book, 240 pages, €29.90
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The only living offspring of dinosaurs are birds. It is still a mystery how their first ancestors descended on Earth.
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