Millions of Years On, Still Evolving
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Version 0 of 1. At age 5, Brian Switek was a Stegosaurus. In a green jumpsuit, with floppy fabric plates sewn along the back, he was set to perform in an Allosaurus vs. Stegosaurus battle at his preschool’s Dinosaur Night. But at the moment of his scripted defeat and mock death at the claws of the Allosaurus boy, the grown-up Mr. Switek recounts in this charming book, young Brian broke character and announced to the audience that Stegosaurus was actually the superior dinosaur. While Allosaurus was fast and fierce, “those attributes would have been of little use against the prominent plates and bone-piercing tail spikes of Stegosaurus.” The teachers must have been furious. The assembled mothers and fathers laughed. Many thousands of children go through a dinosaur phase, of course. But it usually ends, as Mr. Switek writes, “once we discover team sports and kissing under the high school bleachers.” For him, though, the phase persisted as an obsession. Now 30, he blogs about dinosaurs, discusses them on radio and television, and even moved to Utah to live near their fossil remains. He has done his fieldwork and homework and is widely recognized as a reliable and lucid authority on all things dinosaurian. We are beneficiaries of Mr. Switek’s undiminished passion, on display in “My Beloved Brontosaurus.” The book is a delight, coming along when so much has changed in our understanding of dinosaurs, ever since the beginning of a renaissance in dinosaur studies in the 1970s and ’80s. About that title: It is both a memory and a metaphor. The long-necked Brontosaurus, once the epitome of what it was to be a dinosaur, never existed. In their haste to proclaim another species, fossil collectors in the 19th century misidentified the first scrappy remains; only much later were they discovered to belong to a dinosaur properly called Apatosaurus. No sooner was young Brian hooked on dinosaurs than this iconic representative suffered a second extinction — at the hands of science. Mr. Switek, never forgetting his lost love, uses Brontosaurus as a traveling companion through a book about how much our dinosaurs have changed, noting that “the same process that destroyed the titan has revealed clues about prehistoric lives that we never expected to find.” At every turn, it becomes clear that these are not your grandfather’s dinosaurs. Some were hulking behemoths like Supersaurus and Argentinosaurus, well over 100 feet long, but humbler and more diverse creatures keep turning up. Some were probably scaly, but quite a few were covered in feathers. Others were misjudged: they were not always the sluggish, dimwitted tail-draggers knee-deep in swamps, obviously bound for extinction. New lines of evidence, Mr. Switek writes, strongly suggest that dinosaurs were active, fast-growing creatures that would have required high metabolic rates. Dinosaur physiology remains a debated subject. “With a tenure spanning the past 230 million years,” he ventures, “dinosaurs must have had a physiology that was immensely adaptable.” The passage of 230 million years refers to one of the most arresting discoveries, overturning what in one respect dinosaurs are most famous for: their extinction. Dinosaurs evolved around 230 million years ago — presumably benefiting from the Permian mass extinction, only to become victims of the Cretaceous extinction, 66 million years ago. But not all died out: Most paleontologists now agree modern birds are dinosaur descendants. Mr. Switek promises more than he delivers in the chapter on dinosaur sex life. What little is known of eggs, nests and maturation rates is interesting, but not even the best-preserved remains retain any sign of their reproductive organs. As for the actual sexual act, males of some species may have followed practices of today’s lizards and alligators, throwing a foreleg over the female’s back. But what about Kentrosaurus, a relative of Stegosaurus? “If a male Kentrosaurus tried to throw his leg over the back of a crouching female,” the author said, “he’d castrate himself on her sharp spikes.” No skeletons have been found of dinosaurs in flagrante. Other books have dealt with new dinosaur research, but like museum exhibits on the subject, they quickly become outdated. This may be the one book for catching up on what has become of the dinosaurs you thought you knew from grade school. Mr. Switek and his brontosaur spiritual sidekick take you to dig sites, museums and laboratories to experience the rapid changes in dinosaur paleontology. His account is spiced with history of bone wars in the American West, odd facts and asides. For example, there is no such thing as an intercostal clavicle, the bone Cary Grant is frantically searching for in “Bringing Up Baby.” Be prepared for surprises. While you were growing older, dinosaurs underwent an astonishing transformation. Just ask the next 5-year-old you meet. |