For one thing, dinosaurs cannot be experimented upon. Instead, scientists have to interpret the fossil record, which is spotty at best. The first dinosaur discoveries consisted of only a few bones and a handful of teeth. Before long, more complete skeletons began to be found, but the individual pieces were usually scattered about in a jumbled mess of material. Often, they had also been crushed and distorted by the immense pressures at work during and after the process of fossilization.
For that reason, paleontologists had to work hard to assemble dinosaurs into something that resembled real, live animals. In doing so, they relied not only on the available evidence, but also on inference, judgment, and their imagination. Because dinosaurs are in part creatures of the imagination, they reveal a great deal about the time and place in which they were found, studied, and put on display.
Often, paleontologists tasked with reconstructing the fragmentary remains of these animals have been guided in their pursuits by analogies to more familiar objects and circumstances. In the midth century, the British anatomist Richard Owen modeled dinosaurs on pachyderms such as the elephant, whereas early American paleontologists looked to the kangaroo as an anatomical guide.
It was not until the turn of the 20th century that dinosaurs came to be seen as massive, hulking, and lumbering behemoths of prehistory. More recently, many museums have completely overhauled their aging dinosaur displays yet again, to better reflect contemporary views of these creatures as bird-like, active, and fast-moving, with complex social structures.
Dinosaurs simultaneously occupy two widely divergent temporal regimes: They hail from a world in which humans did not exist, yet they are also a product of human history. Dinosaurs tell us a great deal about ourselves.
Their immense size and outlandish appearance all but ensured that dinosaurs would become a mass public spectacle.
But the scarcity of their fragmentary remains and the vast temporal chasm that separates their world from ours meant that it was difficult to know much about these creatures with certainty.
The mystery of what life might have been like during the depths of time allowed people to project their fears and anxieties, as well as their hopes and fantasies, onto these alien creatures. Taken together, these features helped to make dinosaurs into a favorite target for the philanthropic largesse of wealthy elites, which ensured that there would be plenty of resources devoted to the science of vertebrate paleontology.
During the Long Gilded Age, which stretched from the end of Reconstruction to the start of the Great Depression, financial elites like J. Morgan and industrialists like Andrew Carnegie rose to enormous power and influence. This was precisely when dinosaurs from the American West became an icon of science, and the transition to corporate capitalism affected the practice of vertebrate paleontology in surprisingly concrete and far-reaching ways.
Not only did dinosaurs reflect the obsession with all things big and powerful that prevailed at the time, but the science of paleontology itself was profoundly influenced by the creation of large, corporately organized, and bureaucratically managed museums of natural history.
T he first dinosaur fossils were uncovered in England during the s and s, and they acquired the name Dinosauria from the British anatomist Sir Richard Owen in During the decades that followed, many additional fossils came to light, including an especially rich quarry found in a Belgian coal mine that contained dozens upon dozens of Iguanodon specimens.
Nonetheless, the earliest dinosaurs did not stand out among all of the other large, impressive, and strange-looking creatures from prehistory that were being unearthed, which included extinct mammals, such as the Megatherium, and marine reptiles, such as ichthyosaurs and plesiosaurs. This suddenly changed during the last third of the 19th century, with a series of new discoveries in the American West that elicited enormous excitement.
American dinosaurs were a scientific and popular sensation, especially once their fossil remains were mounted as free-standing skeletons in urban museums at the turn of the 20th century. In part, this was due to the fossils themselves. American dinosaurs struck many observers as bigger and more imposing than their European counterparts. But the United States also proved an especially receptive environment for these creatures, a fertile niche that promoted their development into the towering behemoths that continue to wow museum visitors.
At precisely the same time that dinosaur bones became a public sensation, the U. This was due, in no small part, to the development of a robust extractive economy. Simultaneously, more and more people were moving to cities like New York, Philadelphia, Pittsburgh, and Chicago. This included a growing class of wealthy merchants, bankers, and entrepreneurs who bankrolled the process of industrialization.
The railroad linked these two worlds together, tying the city and the countryside into an increasingly dense network of supply and demand. Resources flowed in one direction and capital in the other, with a good many people siphoning off a sizeable profit along the way.
Paleontologists worked hard to assemble dinosaurs. They relied on inference, judgment, and imagination. Because they were so prodigious in size, dinosaurs came to stand in for the power and fecundity of the U. In a striking coincidence, three major dinosaur quarries were simultaneously discovered in the American West during a single field season in the summer of They contained some of the most recognizable fossils, including Stegosaurus, Brontosaurus, and Allosaurus, a close relative of T.
Subsequent decades brought more discoveries to light, catapulting the U. This was still a relatively new science at the time, but the wealth of amazing specimens being unearthed quickly became a scientific and popular sensation. Their discovery was deeply embedded within the extractive economy that dominated the region at this time. In part because the exploitation of mineral resources in precisely this part of the country was so instrumental in propelling the U. Widely heralded as having been larger, fiercer, and more abundant than prehistoric animals from Europe, they meshed well with a conventional narrative that celebrated American exceptionalism.
T heir origin in the deep past ensured that dinosaurs would be associated with evolutionary theory, which was often invoked to explain social, cultural, and economic developments. But dinosaurs did not function as a straightforward image of progress.
Paleontologists have spent decades arranging and rearranging these branches, and a study earlier this year reinvigorated a debate over the shape of the dinosaur family tree. Seeley instead separated these two groups on the basis of their hip shape. There was the Saurischia, which he defined by its roughly lizard-like kind of hip, and included the sauropod and theropod dinosaurs.
And then there were the Ornithischia, which had a more bird-like kind of hip, and comprised armored dinosaurs, horned dinosaurs, duckbill dinosaurs and their relatives.
Birds are technically saurischian dinosaurs with highly-modified hips. But the saurischians and ornithischians are the two main branches with more specific lineages arrayed along them. Other ideas came and went, but this vision of the dinosaur family tree stayed stable.
Then, early in , a study by paleontologist Matthew Baron and colleagues shook things up. Instead of finding the traditional arrangement, the new analysis by Baron and colleagues came up with something different.
Dinosaurs remained as a natural group, but theropod dinosaurs came out as close relatives of ornithischians—normally positioned on the other side of the family tree—and sauropod dinosaurs showed up as relatives of an enigmatic group of early carnivorous dinosaurs called herrerasaurids. The researchers decided to call the theropod-ornithischian group Ornithoscelida a term coined by 19th century naturalist Thomas Henry Huxley and kept Saurischia for the other group.
Months later, a different group of paleontologists upheld the traditional arrangement in a rebuttal , to which followed a rebuttal to the rebuttal. A new fossil or analysis can sow more confusion that understanding upon announcement, says Pritchard. This is just how science works: Just as dinosaurs evolved and changed, so does the science, to incorporate new evidence and theories.
Riley Black is a freelance science writer specializing in evolution, paleontology and natural history who blogs regularly for Scientific American. Ask Smithsonian A Smithsonian magazine special report. What's a dinosaur, anyways? The answer is in the evolutionary tree. Hips don't lie: Today we separate the clade Dinosauria into two groups, Saurischia lizard-hipped, above and Ornithischia bird-hipped, below.
I'm not. I've come across some weird websites in my Google searches. For instance, the word dinosaur. It didn't exist until like There was no word for dinosaur. And then all of a sudden in the next years, after a British scientist comes up with this word dinosaur and describes it in a medical journal, people started finding fossils.
And I'm thinking to myself alright, humans we've been here since 10, BC.
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