Megalosaurus (1824): William Buckland Names the First Dinosaur

Megalosaurus was the first dinosaur ever given a scientific name. On 20 February 1824 the Oxford geologist William Buckland described it to the Geological Society of London from bones found in the slate quarries of Stonesfield, Oxfordshire. Calling it a “great fossil lizard”, Buckland opened the scientific study of the animals that would later be called dinosaurs.

Background: bones from the Stonesfield slate

Stonesfield, a village about 15 kilometres north-west of Oxford, was known for its thin, stone roofing “slates”, dug from underground mines. The rock formed in a shallow coastal sea and nearby land in the Middle Jurassic, around 166 million years ago, and it often contained fossils of plants, insects, fish, turtles and the occasional large bone.

Giant bones had been reported in Oxfordshire long before. In 1677 Robert Plot illustrated the lower end of a huge thigh bone in his Natural History of Oxford-shire; he thought it might come from a giant human. The bone is now lost, but from Plot’s drawing it was probably from a Megalosaurus or a similar animal.

From the early 19th century bones from Stonesfield were gathered into the Oxford collections. They included part of a lower jaw with blade-like teeth, vertebrae, ribs, parts of the hip and limb bones. Buckland, who became Oxford’s first Reader in Geology in 1818, studied them for several years. The bones were not found together, and it is not certain that they all came from a single animal, a problem that later complicated the study of the genus.

Buckland’s description of 1824

William Buckland was a clergyman, a colourful lecturer and a leading figure in English geology. The French anatomist Georges Cuvier saw the Stonesfield bones when he visited Oxford in 1818 and encouraged their description.

On 20 February 1824, at the meeting where he also became president of the Geological Society, Buckland read his “Notice on the Megalosaurus or great Fossil Lizard of Stonesfield”. It was published the same year in the society’s Transactions, with detailed drawings by Mary Morland, a talented naturalist and illustrator who married Buckland in 1825.

The name Megalosaurus, “great lizard”, had already appeared in print in 1822 in a book by James Parkinson, who seems to have known of Buckland’s plans. Buckland’s paper was the formal description. The species name bucklandii was added later in the 1820s, honouring Buckland.

What Buckland got right and wrong

Buckland correctly identified the animal as a reptile and a meat-eater, judging from its curved, serrated teeth, which he compared to a combination of knife and saw. He also recognised that it was far larger than any living lizard.

Lacking a complete skeleton, he imagined it as a giant lizard walking on four sprawling legs. Comparing the bones with those of modern lizards, he estimated a length of about 40 feet (12 metres) and a bulk similar to an elephant. Modern studies suggest it was about 6 to 9 metres long, weighed roughly 0.7 to 1 tonne and walked on its two hind legs, with shorter arms.

A new group: the dinosaurs

In the years after 1824, more giant reptiles were found in England. Gideon Mantell named Iguanodon in 1825 and Hylaeosaurus in 1833. In 1842 the anatomist Richard Owen recognised that these three animals shared features, such as hips fused to several vertebrae, that set them apart from other reptiles. He placed them in a new group, the Dinosauria, meaning “terrible lizards”.

Owen pictured Megalosaurus as a heavy, mammal-like quadruped, and in that form it was built as a life-size sculpture among the Crystal Palace dinosaurs in 1854. Charles Dickens captured the public mood in the opening of Bleak House (1852–1853), imagining a Megalosaurus “waddling like an elephantine lizard up Holborn Hill”.

A wastebasket for meat-eaters

For more than a century Megalosaurus became a “wastebasket taxon”: fragments of almost any large meat-eating dinosaur from around the world were assigned to it. At one time dozens of species bore the name, many from rocks of very different ages.

Modern palaeontologists have narrowed the genus down to the Oxfordshire species, Megalosaurus bucklandii. A detailed redescription by Roger Benson in 2010 identified the features that distinguish it and placed it among the megalosaurids, a family of large theropods. The theropods are the group of mostly meat-eating dinosaurs that also gave rise to birds. The lower jaw that Buckland described was formally chosen as the specimen that defines the species.

What Megalosaurus was really like

Modern palaeontologists picture Megalosaurus as a large, two-legged predator, broadly similar in build to later meat-eaters such as Allosaurus, though less well known. It had a long, narrow skull with curved, serrated teeth, strong arms ending in three clawed fingers, powerful hind legs and a long tail that balanced the front of the body.

It lived around 166 million years ago, in the Bathonian stage of the Middle Jurassic. At that time much of what is now southern England lay under warm, shallow seas dotted with low islands and lagoons. Megalosaurus probably hunted on these coastal lands, and it may have preyed on plant-eating dinosaurs such as early sauropods and stegosaurs whose remains are found in rocks of similar age in Britain.

Fossil trackways in Oxfordshire help complete the picture. At Ardley quarry, north of Oxford, large three-toed footprints of the same age were found in 1997. They were probably made by a megalosaur-like predator and show that it walked on two legs with a narrow stride, exactly as later scientists had come to suspect.

Myths and facts

• “Megalosaurus was the first dinosaur ever found”: large dinosaur bones had been dug up long before, including the thigh bone illustrated by Robert Plot in 1677. Megalosaurus was the first to be named and scientifically described.
• “Buckland called it a dinosaur”: the word did not yet exist. Buckland called it a giant lizard, and the term Dinosauria was coined by Richard Owen in 1842.
• “Megalosaurus is one of the best-known dinosaurs”: despite its fame, it is still known only from incomplete bones. No complete skeleton or skull has ever been found.

Key people

• William Buckland (1784–1856): Oxford geologist and clergyman who described Megalosaurus and later became Dean of Westminster.
• Mary Morland (Mary Buckland): naturalist and illustrator who drew the bones for the 1824 paper.
• Georges Cuvier: French anatomist who examined the bones in 1818 and supported their identification.
• Gideon Mantell: Sussex geologist who named Iguanodon and found further Megalosaurus material.
• Richard Owen: anatomist who coined the term Dinosauria in 1842.

Timeline

• 1677: Robert Plot illustrates a giant thigh bone from Oxfordshire.
• 1818: Georges Cuvier sees the Stonesfield bones in Oxford.
• 1822: The name Megalosaurus appears in a book by James Parkinson.
• 1824, 20 February: Buckland describes Megalosaurus to the Geological Society of London.
• 1825: Mantell names Iguanodon; Buckland marries Mary Morland.
• 1842: Richard Owen names the Dinosauria, including Megalosaurus.
• 1854: A life-size Megalosaurus sculpture is unveiled at Crystal Palace, Sydenham.
• 2010: Roger Benson publishes a modern redescription of Megalosaurus bucklandii.

Why it matters

Megalosaurus was the first dinosaur to enter science, and its naming in 1824 began a field that has since grown to include well over a thousand species. Together with the marine reptiles collected by Mary Anning, it helped convince scholars that the Earth had once been ruled by strange, now-vanished creatures.