Huge fossilized bones that emerged from slate quarries in Oxfordshire, England, in the early 17th century were an immediate mystery.
In a world where evolution and extinction were unknown concepts, the experts of the time searched for an explanation. Perhaps, they thought, they belonged to a Roman war elephant or a giant human.
It was not until 1824 that William Buckland, the first professor of geology at the University of Oxford, described and named the first known dinosaur, based on a lower jaw, vertebrae and limbs found in those local quarries. The largest femur was 2 feet, 9 inches long and almost 10 inches in circumference.
Buckland mentioned the creature whose bones belonged to Megalosaurus, or large lizard, in a scientific paper he presented to the newly formed Geological Society in London on February 20, 1824. Judging by the shape of its teeth, he believed it was a carnivore over 40 feet long. (12 meters) long with "the largest part of an elephant." Buckland thought it was probably an amphibian and lived partly in land and water.
"In some ways he was right about a lot. This was a group of extinct giant reptilian creatures.
This was a radical idea," says Steve Brusatte, a paleontologist at the University of Edinburgh and author of "The Rise and Fall of the Dinosaurs: A New History of Their Lost World."
"We all grew up watching dinosaur cartoons and 'Jurassic Park,' with dinosaurs on our lunchboxes and toys. But imagine a world where the word dinosaur doesn't exist, where the concept of a dinosaur doesn't exist, and you were the first people to realize this just by looking at some of the Earth's big bones.
The word dinosaur did not emerge until twenty years later and was coined by anatomist Richard Owen, founder of the Natural History Museum in London, based on common features he identified in his research on Megalosaurus and two other dinosaurs, Iguanodon and Hylaeosaurus. were first described in 1825 and 1833 respectively.
The story continues
The Megalosaurus article cemented Buckland's professional reputation in the new field of geology, but its significance as the first scientific description of a dinosaur only became apparent in retrospect.
At the time, Megalosaurus was overshadowed in the public imagination by the discovery of complete fossils of giant marine reptiles such as the ichthyosaur and the plesiosaur, collected by paleontologist Mary Anning on England's Dorset coast. No complete skeleton of Megalosaurus has been found.
But Megalosaurus did have an impact on popular culture. Charles Dickens, who was friends with Owen, imagined meeting a Megalosaurus on the muddy streets of London at the opening of his 1852 novel, "Bleak House."
It was also one of three model dinosaurs exhibited in 1854 at London's Crystal Palace, home to the world's first dinosaur park. It's still there. Although the shape of his head is largely correct, we know today that he was about 6 meters tall and walked on two legs, not four.
Who was Bokland?
It is not clear how Buckland developed his expertise as a geologist.
An ambitious and charismatic scholar, he read classics and theology at Oxford, graduating in 1805 and taking a wide range of classes, including anatomy, says Susan Newell, a historian and associate professor at the University of Oxford's Museum of Natural History. He also interacted with other celebrated natural scientists of the time, such as Charles Cuvier in France, who was famous for his work comparing living animals to fossils.
"(Buckland) was the first person to really start thinking hard about what's going on with all these strange fossils turning up, down the road in this quarry in Oxford, and he started paying local quarries to get (fossils and)... save stuff for him," Newell said.
"He started putting the puzzle together."
A year after his Megalosaurus article was published, Buckland married his unofficial assistant, Mary Morland, who was a talented naturalist in her own right and the artist of the illustrations of Megalosaurus fossils that appeared in the seminal article.
Later in his career, Buckland recognized that most of the United Kingdom had once been covered in ice sheets after a trip to Switzerland, realizing that a period of ice age had shaped the British landscape rather than a Biblical flood.
Newell said Buckland's scientific career ended prematurely, with him succumbing to a kind of nervous breakdown that kept him from teaching. He died in 1856 in an asylum in London.
What we learned
For paleontologists, the 200th anniversary of the first scientific naming of a dinosaur is an opportunity to take stock and look back at what the field has learned over the past two centuries.
Defined by their disappearance, dinosaurs were once thought to be evolutionary failures. In fact, dinosaurs survived and thrived for 165 million years - far longer than the roughly 300,000 years that modern humans have roamed the planet so far.
Today, about 1,000 species of dinosaurs have been named. And according to Brusatte, about 50 new dinosaur species are discovered every year.
"Really, science is still in the discovery phase. Yes, it is now 200 years old, but we have only found a small fraction of the dinosaurs that ever lived," Brusatte said. "Today's birds are the descendants of dinosaurs. There (are) more than 10,000 species of birds living today. And of course dinosaurs lived for over 150 million years. So do the math. There were probably thousands, if not millions, of different types of dinosaurs."
In the 1990s, fossils unearthed in China definitively revealed that dinosaurs had feathers, confirming a long-held theory that they are the direct ancestors of the birds that flit around in backyards.
It's not just amazing fossil discoveries that are making the present a golden age for paleontology. New technology such as CT scans and computational methods allow paleontologists to reconstruct and understand dinosaurs in much greater detail.
For example, some feathered fossils preserve small structures called melanosomes that once contained pigment. By comparing the melanosomes with those of living birds, scientists can determine the possible original colors of the feathers.
There is still much to learn. It's not entirely clear how and why dinosaurs grew so large, nor is it really known what sounds the creatures might have made.
"I think it's almost impossible for us to think back to a world where people didn't know dinosaurs," Brusatte said.
"But there will be things in the future where people will say, how did we not know that in 2024? (This anniversary) should give us some perspective."
London Natural history museum And The Geological Society will host special events in 2024 to mark the 200th anniversary of the naming of the first dinosaur.
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