What we’ve learned and what we still don’t know

(CNN) — Huge fossil bones unearthed from slate mines in Oxfordshire, England in the late 17th century were immediately surprising.

In a world where evolution and extinction were unknown concepts, experts of the time were looking for explanations. Perhaps, he thought, they belonged to a Roman war elephant or a giant human.

By 1824 William Buckland, the first professor of geology at the University of Oxford, described and named the first known dinosaur based on lower jaw, vertebrae and limb bones found in local quarries. The largest thigh bone measured 33 inches long and approximately 10 inches in circumference.

Buckland named the creature Megalosaurus, or great lizard, from the bones in a scientific paper presented to the newly formed Geological Society of London on February 20, 1824. From the shape of its teeth, they believed it was a carnivore. More than 40 feet (12 m) tall with a more “elephant shape”. Buckland thought it was probably amphibious and lived partly on land and in water.

“In a way he got a lot of things right. It was a group of extinct giant reptiles.
It was a revolutionary idea,” said paleontologist and author Steve Brusatte of the University of Edinburgh. The Rise and Fall of the Dinosaurs: A New Story of Their Lost World.

“We all grew up watching dinosaur cartoons and ‘Jurassic Park’ with dinosaurs in our lunchboxes and toys. But imagine a world where the word dinosaur doesn’t exist, where the concept of dinosaur doesn’t exist, and you were the first people to realize it by looking at some big bones on Earth.

The term dinosaur did not appear until 20 years later, coined by anatomist Richard Owen, founder of the Natural History Museum in London, based on shared characteristics identified in his studies. megalosaurus And two other dinosaurs, Iguanodon And HylaeosaurusWhich were first described in 1825 and 1833 respectively.

articles about megalosaurus It strengthened Buckland’s professional reputation in the new field of geology, but its importance as the first scientific description of dinosaurs was apparent only in retrospect.

in that moment, megalosaurus The discovery of complete fossils of giant marine reptiles such as ichthyosaurs and plesiosaurs, collected by paleontologist Mary Anning off the coast of Dorset, England, captured the public imagination. No complete skeleton has been found. megalosaurus,

But megalosaurus It had an impact on popular culture. Charles Dickens, who was a friend of Owen, imagined encountering a Megalosaurus on the muddy streets of London at the beginning of his 1852 novel, bleak House.

An illustration shows geologist William Buckland teaching in a lecture hall at the University of Oxford, February 15, 1823. (The Metropolitan Museum of Art)

It was one of three dinosaur models displayed at the Crystal Palace in London in 1854, the world’s first dinosaur park. It is still there today. Although the shape of its head is largely accurate, today we know that it was about 6 meters (about 20 feet) long and walked on two legs, not four.

Who was Buckland?

It is unclear how Buckland developed his expertise as a geologist.

An ambitious and charismatic scholar, he read classics and theology at Oxford, graduating in 1805, and took many classes, including anatomy, said Susan Newell, a historian and research associate at the University of Oxford’s Natural History Museum. He was also in contact with other famous natural scientists of the time, such as Charles Cuvier in France, who was famous for his work comparing living animals with fossils.

“(Buckland) was the first person who really started to think deeply about what was going on with all these strange fossils that were being found just down the road in this quarry in Oxford, and he helped local people find them. Started paying the miners.” (Fossils and) …keep things for him,” Newell said. “He started putting the puzzle together.”

One year after the publication of his article megalosaurusBuckland married his informal assistant, Mary Morland, a talented naturalist and artist of fossil illustration in her own right. megalosaurus Which was published in an unprecedented article.

Later in his career, Buckland recognized that much of the United Kingdom was covered by ice sheets after a visit to Switzerland, understanding that glacial periods rather than the Biblical flood had shaped the British landscape.

dinosaur statue megalosaurus In Crystal Palace Park, London, 1854. At the time, paleontologists thought that the prehistoric creature walked on four legs. (Loop Images Ltd/ Alamy Stock Photo)

Newell stated that Buckland’s scientific career ended prematurely due to some form of mental crisis, which prevented him from teaching. He died in a London hospital in 1856.

What have we learned about dinosaurs

For paleontologists, the 200th anniversary of the first scientific naming of dinosaurs is an opportunity to take stock and see what the field has learned over the past two centuries.

Defined by their demise, dinosaurs were once considered an evolutionary failure. In fact, dinosaurs lived and thrived for 165 million years, far longer than the approximately 300,000 years that modern humans have roamed the planet.

Today, approximately 1,000 species of dinosaurs have been named. And according to Brusatte, about 50 new species of dinosaurs are discovered every year.

“In fact, the science is still in the discovery stage. Yes, it’s 200 years old now, but we’ve only got a tiny fraction of the dinosaurs that ever existed,” Brusatte said. “Today’s birds are descendants of dinosaurs. At present more than 10,000 species of birds live here. And of course, dinosaurs lived for more than 150 million years. Then do the math. “There were probably thousands, if not millions, of different species of dinosaurs.”

In the 1990s, fossils discovered in China definitively showed that dinosaurs had feathers, confirming the long-held theory that they are the direct ancestors of backyard birds.

It is not just the amazing fossil discoveries that make this the golden age of paleontology. New technologies, such as computed tomography and computational methods, allow paleontologists to reconstruct and understand dinosaurs in greater detail.

an engraving of the jaw megalosaurus Based on paintings by Mary Morland Information about Megalosaurus or the great Stonesfield fossil lizard, 1824, by William Buckland.
(The Picture Art Collection/ Alamy)

For example, small structures called melanosomes that once contained pigment are preserved in some feather fossils. By comparing melanosomes of modern birds, scientists can determine possible original feather colors.

There is still a lot left to learn. It is not entirely clear how or why dinosaurs grew so large, nor is it known exactly what noises the creatures might have made.

Today, paleontologists believe that megalosaurus I walk on two legs. (Julian Behl/PA Wire/AP)

“I think it’s almost impossible for us to think of a world where people wouldn’t know about dinosaurs,” Brusatte said.

“However, there will be things in the future where people will say how did we not know in 2024. (This anniversary) should give us some perspective.”

Source link

About Admin

Check Also

Artemis 2 astronauts are already preparing to return to Earth

Their journey around the Moon is only scheduled for September 2025, but the four astronauts ... Read more

Leave a Reply

Your email address will not be published. Required fields are marked *