Register for our Voices Dispatches email to receive a comprehensive summary of the top opinions from the past week.
Subscribe to our complimentary Voices newsletter, delivered every week.
On February 20, 1824, William Buckland, an English naturalist and theologian, presented to the Geological Society of London findings from a slate quarry near Oxford. He described the discovery of a massive jaw and limb bones in the village of Stonesfield.
Buckland recognized that these fossils belonged to a huge bygone reptile, and gave it a formal scientific name: Megalosaurus, meaning “great lizard.”
As a result, the initial dinosaur was formally acknowledged, even though the term “dinosaur” was not invented until the 1840s.
According to paleontologist Steve Brusatte from the University of Edinburgh, the discovery sparked our initial interest in dinosaurs. This finding triggered a rush for fossils, leading people to search for more massive bones in England and other areas.
During the past 200 years, the study of dinosaurs has thrived, revealing details about their appearance, behavior, evolution, and eventual extinction. These creatures inhabited the Earth from approximately 231 million years ago to 66 million years ago, in what is known as the Mesozoic Era. Some of their descendants, modern-day birds, still exist today.
According to Emma Nicholls, a paleontologist at the Oxford University Museum of Natural History, our knowledge of dinosaurs has undergone significant changes since the 1800s. The museum houses the Megalosaurus fossils that were studied by Buckland.
Brusatte stated that Buckland and other naturalists from the 19th century would be amazed by the vast amount of information we have acquired about dinosaurs.
The example of Megalosaurus is noteworthy. Buckland initially believed it to be a 66-foot (20-meter) long lizard that walked on four legs and could survive on both land and water. However, current scientific understanding reveals that it was not quadrupedal or a lizard, but actually part of the theropod group, which includes carnivorous dinosaurs like Tyrannosaurus and Spinosaurus, and was approximately 30 feet (9 meters) in length.
Brusatte described the creature as running on its back legs and pursuing its food, using its sharp claws and teeth to overpower its targets.
Buckland, along with his contemporaries, was unaware of the true extent of time that had passed since dinosaurs roamed the Earth. They believed the planet to be only a few thousand years old. However, modern scientists have determined that Earth is actually around 4.5 billion years old. Megalosaurus, a type of dinosaur, lived approximately 165 million years ago.
Geologists took many years to comprehend the true age of the Earth and the evolution of life over long periods of time. The discovery of fossils, including dinosaurs, played a significant role in changing people’s perspective on their role in the world, according to Brusatte.
In 1841, Richard Owen, an English biologist, identified that the fossils discovered in southern England, including Megalosaurus, Iguanodon, and Hylaeosaurus, belonged to a shared group. He named this group “Dinosauria” during a lecture, and published his findings the following year.
Later on, fossils of Hadrosaurus and Dryptosaurus found in the state of New Jersey in the United States revealed that certain dinosaurs were able to walk on two legs, challenging the previous belief that they were similar to reptilian rhinoceroses. In the 1870s, the discovery of complete dinosaur skeletons, first in the American West and then in Belgium and other places, provided evidence of the unique anatomy and wide variety of dinosaurs.
During the 1960s, the discovery of the small, carnivorous dinosaur Deinonychus caused a stir in the field of dinosaur research, marking the beginning of a new era known as the “Dinosaur Renaissance.” This finding demonstrated that dinosaurs could be both small and nimble. Some were even anatomically similar to early birds like Archaeopteryx, providing evidence for the evolution of birds from small, feathered dinosaurs. This sparked a discussion about whether or not dinosaurs were warm-blooded like birds, challenging the long-held belief that they were slow, sluggish, and cold-blooded.
According to paleontologist Thomas Holtz from the University of Maryland, there was a growing focus on dinosaur growth, the utilization of CT scans, and analytical techniques for understanding evolutionary relationships and biomechanical function in the years that followed. This contributed to a more dynamic and biological understanding of dinosaurs as living creatures.
Scientists use CT scanners to create digital representations of dinosaur brains and ears using cranial fossils. This allows for a deeper understanding of their senses, such as sight, hearing, and smell. Through this technology, researchers are also able to determine the color of dinosaurs based on the preservation of microscopic melanosome bubbles that contain pigments in skin or feathers.
Over 2,000 types of dinosaurs have been identified and paleontology is a thriving, global field of study. Exciting discoveries of fossils are occurring in various locations including China, Argentina, Brazil, South Africa, and Mongolia.
According to paleontologist Hans-Dieter Sues from the Smithsonian Institution’s National Museum of Natural History in Washington, the most significant discovery in recent years about dinosaurs is that theropods, a type of meat-eating dinosaur, had feathers instead of scales. It was also found that some theropods had fully developed feathers on their arms, even though they were not able to fly for various reasons.
Sues stated that it is likely that these feathers, which were frequently vibrant, served as insulation for the body and may have also been used for display in certain species.
The disappearance of the dinosaurs had been a mystery to researchers for a long time, with different theories proposed, ranging from believable to absurd. Some even suggested that the tiny mammals of that era were responsible for consuming dinosaur eggs.
In 1980, scientists discovered a layer of sediment that accurately dated back to the end of the dinosaur era. This layer contained large amounts of iridium, a substance frequently found in meteorites, suggesting that a massive space object had collided with Earth. The Chicxulub crater, measuring 112 miles (180 km) in diameter, was later identified as the location where an asteroid struck, causing the extinction of 75% of Earth’s species, including the dinosaurs.
If the asteroid had not collided with Earth, would dinosaurs continue to dominate instead of mammals – including humans – who inherited a damaged planet?
Holtz stated that it is highly likely that mammals appeared shortly after the first dinosaurs, but remained in their shadow for millions of years. While mammals during the Mesozoic era were successful and varied, they were limited to smaller sizes.
Holtz explained that the dinosaurs would have faced the gradual process of the world becoming drier and cooler, leading to a decrease in forests and an increase in grasslands. However, this transformation would have been slow enough for the dinosaurs to develop adjustments to the changing environment, similar to how large mammals did.
Researchers have analyzed the metabolic processes of dinosaurs by utilizing a formula that takes into account their body mass, as indicated by the size of their thigh bones, and their growth rates, as evidenced by the presence of growth rings in fossil bones similar to those found in trees. The findings indicate that dinosaurs fell somewhere in between the warm-blooded and cold-blooded animals of today.
Researchers have further developed their evaluation of the dimensions of different dinosaurs, specifically the sauropod group which consisted of the biggest land creatures in the history of our planet. In a 2023 analysis utilizing measurements of limb bones, Argentinosaurus was deemed the reigning heavyweight champion, measuring approximately 115 feet (35 meters) in length and weighing around 76 metric tons.
The investigation is still ongoing, even after 200 years have passed.
Holtz stated that beyond the world of modern technology, there remain numerous untamed regions across the globe that have yet to be fully explored in terms of paleontology. These areas hold the potential for uncovering new species from the dinosaur era. It is highly likely that there are entire groups of dinosaurs that have yet to be discovered.