Princeton University Press
What color were the dinosaurs? When watching Jurassic Park movies, the answer seems obvious: grey, brown or, best of all, dull green.
In a new book, British paleontologist David Hohn asked dryly: “Has there ever been a more tedious coloring of animals than the ones in those movies?”
In How fast did T. Rex run?, Han sets the record straight. Some dinosaurs sported red, white, or iridescent black colors, and showed patterns of colorful patches, spots, or stripes. For example, a small dinosaur called Sinosauropteryx from China has been described as “a ‘ginger’ with white stripes.”
How do scientists reconstruct the colors of animals that have been extinct for 65 million years (except for birds, and more on those in a moment)? The key, Hohn explains, are “packages of pigment” called melanosomes found in cells. Many living animals, including humans, have melanosomes and are also found in rock formations that contain preserved dinosaur skins or feathers. It is extraordinarily fortunate that the shape of a melanosome exactly reflects its color type: “So while fossil melanosomes no longer have any color, we know what they were supposed to be and from this we can infer colors. “
Hawn set out to write a book that emphasized what is known so far about dinosaurs. (With regard to the title, how fast T. Rex ran is one of the unknown.) He achieves this balance beautifully. The volume is jam-packed with captivating descriptions of advances in dinosaur science, while also serving as a handbook for anyone wishing to identify central gaps in our knowledge. Regarding color information, for example, he laments the “disappointingly incomplete” nature of the data: whether the colors were muted or bright is unclear – and so far only six dinosaurs have been studied. We have no idea of the extent of color variation across species, sexes or individuals over time.
Although I am fascinated by seeing or learning about dinosaur fever, almost any animal in childhood or adulthood, I still don’t get it. I was fascinated by Hone’s inviting way to deliver everything from the basics to the more advanced aspects of dinosaur science.
During their reign on Earth, dinosaurs—about 1,500 species among them—lived in nearly every ecosystem on the planet. Although the stereotype of tropical swamp-dwelling creatures is firmly embedded in popular culture, dinosaurs are in fact “on mountains, in deserts, lakes and coastlines, in temperate and coniferous forests, and in all kinds of temperatures, rain, snow, wind and wind”. lived in Other changes in both climate and weather.”
Dinosaurs are divided into three types or groups. Theropods are bipedal, often carnivorous dinosaurs including Tyrannosaurus and Velociraptor. Sauropodomorphs like Brontosaurus and Brachiosaurus walked around, and had massive bodies and long necks. Ornithischians are plant eaters, often displayed bony plates and crests, and include Stegosaurus and Triceratops.
How long was the reign of dinosaurs? Here, I present a complaint. At various points Hohn says that the dinosaurs were around “130-some” million years, 150 million years, or “180-ish million years”. Dinosaurs are not fully known in science, and an unexplained anomaly of 50 million years is not trivial, even in a book that is confusing for readers.
But when he delves into the details, Hawn is brilliant. In addition to the appearance of dinosaurs, he covers the changing aspects of extinction, origin, conservation, diversity, evolutionary patterns, habitat, anatomy, mechanics, physiology, cover, reproduction, behavior, ecology, dinosaur ancestry, and research and communication does. It’s hard to pick a favorite here, but the chapter on breeding was the most mind-blowing.
Hon included in that chapter an image, taken by himself in China, of a nest of eggs laid and curated by a giant oviraptorosaur. The caption outlines what we can see in the picture: “The eggs are laid in several layers in a ring and the animal is probably sitting in the middle.” There is an irony in the fact that this dinosaur displayed parental care of eggs: “oviraptorosaur” means “egg thief.” When researchers first uncovered the skeletons of this dinosaur with eggs, the assumption was of eating the eggs of other dinosaurs, not brooding. The dinosaurs called titanosaurs apparently did not crumble, but instead, judging by the location of their egg beds and the structure of the eggshells, the eggs were heated by the heat of the volcano. That behavior is “completely unexpected,” notes Hohn.
We still don’t understand much about dinosaur reproductive biology. Did the female or the male sit on the eggs, or did they trade? With a bit of support for mating moments, Hone again displays some dry humour: “How on earth are you supposed to have two weird and very prickly ankylosaurs, or some giant multi-ton bipedal theropods, or the biggest sauropods?”
There are ten thousand dinosaur species alive today: birds, of course. Hahn has much to say about the origins of the bird lineage, again balancing strong evidence with open questions. Birds and dinosaurs coexisted for about 100 million years, so we know that birds did not originate until after the famous extinction event of 65 million years ago. Flying reptiles called pterosaurs and non-avian dinosaurs all disappeared at that point, and “very large numbers” of bird lineages too. The surviving birds were species that were largely confined to land but still capable of flight, apparently referring to the fact that plantation birds experienced more severe habitat loss.
And what about that extinction event? Yes, the asteroid hitting Mexico’s Yucatan Peninsula remains the leading contender to explain the loss of dinosaurs. But Hawn intriguingly complicates that story. He raises the possibility that if the asteroid had “passed past Earth without a scratch” the dinosaurs would have gone extinct anyway as they struggle to survive in a world already severely altered by volcanic eruptions. Was doing.
At the back of the book, at the back of the reference section, is Hawn’s request for readers to fill out a brief online survey that attempts to find out who might be inspired to learn more about dinosaurs. “Keeping track of the impact my work has on the general public helps me keep doing it,” notes Hone. I guess he’s going to hear a lot of good news very soon.
Barbara J. King is a biological anthropologist emerita at William & Mary. Animals’ best friend: Putting compassion to work for animals in captivity This is his seventh book. find him on twitter @bjkingape