A key hindrance to understanding fossils is that you first have to understand rocks and how they form. Although some earlier thinkers' speculations came close to the truth, it wasn't until the 17th and 18th Centuries that a combination of field observations and laboratory work found the answer: rocks were recycled bits of previously existing rocks, and that different pathways melting and cooling; recrystallization; or fragmentation and reassembly produced different types of rocks.
It was in this last pathway what would be called sedimentary rocks that fossils would be found. Their remains were buried in sand, silt, or mud, and that this sediment later was transformed into rock. With access to the large and growing collections of modern and fossil specimens of animals and plants, they were able to describe the particular features of each species. Given this database, Cuvier was able to establish that at least some of the fossils being discovered were not any known living species, but instead must be extinct.
Cuvier and colleagues also established that there was not a single "prehistoric age", but that instead different assemblages of fossils were earlier or later than others. For instance, mammoths and mastodons were among the youngest closest to us in time of fossils, and that different mammals more different than any living ones were found in earlier times.
Among the major sets of discoveries in the late s and early s were a series of giant reptile fossils older than the mammal fossils. These were among the specimens that first helped demonstrate that fossils were in fact remains of extinct creatures, and not simply to bodies of still-extant species.
These included the "Great Animal of Maastricht" , a giant marine reptile eventually recognized by Cuvier and others as a huge sea lizard, and now named Mosasaurus : the first giant fossil reptile known to Science! Others include the discoveries of fossil collector Mary Anning : fish-like Ichthyosaurus and long-necked Plesiosaurus.
In addition to these sea reptiles, flying reptiles such as Pterodactylus and Dimorphodon. So it became apparent that before the age in which mammals were the dominant animals, there was an "Age of Reptiles". But so far these discoveries were swimmers and fliers: what lived on land during this age? The first of these was made by Oxford geologist Reverend William Buckland. Only a few parts were discovered: jaw bones with blade-like teeth as well as some backbones, hip bones, and limb bones.
This animal was formally named Megalosaurus "big lizard" in , and thought to be a giant version of modern monitor lizards. The next major discovery were made in the in the Weald region of southern England, by husband and wife team Dr. Gideon and Mary Ann Mantell. These included teeth were leaf-shaped, reminiscent of the modern Iguana , a primarily herbivorous reptile, as well as limb bones, vertebrae, and so forth.
When Gideon Mantell formally described the animal he called it Iguanodon "iguana tooth" , and imagined it to be an immense version of the iguana. Latest Episode. Skip to content Facbook Twitter Tumblr Reddit Email Science Diction is a bite-sized podcast about words—and the science stories behind them. Note: This piece has been updated. Please find the original article below.
First Known Use: Etymology: A combination of two Greek words introduced a creature previously unknown to the world. Credit: Wikimedia Commons Just one year later, a doctor named Gideon Mantell pondered the teeth and bones of another reptile that had been pulled out of the sandstone in a nearby forest in Sussex. Credit: Wikimedia Commons When Sir Richard Owen, a naturalist and paleontologist, took a look at the three fossils together, he had a stunning realization: Unlike contemporary reptiles, both the Megalosaurus and Iguanodon had five vertebrate at the base of their spine that appeared to have fused together during their lifetime.
Dino Dining The lizards were not terrifying enough, however, to prevent Owen from eating dinner inside a dinosaur. Credit: Wikimedia Commons Original piece by Howard Markel, published July 6, Everybody likes a good dinosaur story, but one of the best dinosaur stories of them all centers on the man who gave these remarkably extinct beasts their name.
Calling all word nerds! Sign up for an email about words and language, and updates about the Science Diction podcast. Meet the Writers Howard Markel. Johanna Mayer. Everybody likes a good dinosaur story, but one of the best dinosaur stories of them all centers on the man who gave these remarkably extinct beasts their name. Some time around , Owen began studying the bony remains of extinct races of reptiles: the carnivorous Megalosaurus, the herbivorous Iguanodon and the armored Hylaeosaurus.
The result was dinosaurian or dinosaurs. The Oxford English Dictionary also describes the origin of the slang use of dinosaur, which refers to someone or something that has failed to adapt to a new environment or circumstances. But based on a fossil uncovered in the seventeenth century, it could have been known by a different name.
He noted that it looked almost exactly like the lower part of a human femur. He included an illustration of the peculiar fossil in his book The Natural History of Oxford-shire - but the piece lacked a name.
The fossil was uncovered in the Oxfordshire parish of Cornwell. Although Plot didn't detail the rock type that the fossil was found in, quarries in that part of the UK consist of limestone dating to the Mid Jurassic.
In volume five he dubbed Plot's fossil Scrotum humanum, simply stating that 'stones have been found exactly representing the private parts of a man'.
But as it was determined many years later, neither Plot nor Brookes knew what the fossil really was. The Linnaean system for scientific naming began in , five years before the bone was described. Plot's fossil was later thought to be from Megalosaurus.
As Scrotum had been described 60 years earlier, Megalosaurus could have been considered a synonym. However, Plot's fossil is now lost and scientists today can't confirm whether it was Megalosaurus. In the s the International Commission on Zoological Nomenclature determined that Scrotum humanum did not constitute a valid scientific name.
Plot's illustration of the unnamed fossil that he speculated could be from a giant human Fig. It was later thought to be from Megalosaurus.
Brookes's descriptive name was therefore officially disregarded, and Megalosaurus retained its claim to fame as the first official dinosaur. Owen's Dinosauria almost met an end in the late s.
Increasing fossil reptile discoveries were being made and palaeontologists began searching for ways to tie the animals together. Two key groups emerged: the ornithischians 'bird-hipped' and saurischians 'lizard-hipped'. In , palaeontologist Harry Seeley published a paper on these two new groups and denounced Owen's Dinosauria, stating that it 'has no existence as a natural group of animals'. The concept of the clade Dinosauria drifted out of favour. It was considered nothing but a miscellany of only distantly related reptiles.
An illustration of a Lower Jurassic Period scene about - million years ago showing an ornithiscian Megalosaurus top and saurischian Scelidosaurus. But evidence gathered in the s, including that birds evolved from a group of dinosaurs, showed that Dinosauria was not an obsolete group after all. Led primarily by American palaeontologists Robert Bakker and John Ostrom, the 'dinosaur renaissance' began, bringing dinosaurs back into the limelight, to be considered a valid group by palaeontologists once again.
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