The First Described and Validly Named Dinosaur: Megalosaurus
In 1676, the lower part of a massive femur was discovered in the Taynton Limestone Formation of Stonesfield limestone quarry, Oxfordshire. The bone was given to Robert Plot, Professor of Chemistry at the University of Oxford and first curator of the Ashmolean Museum. Plot published a description of it in 1677 in the Natural History of Oxfordshire. The illustration that accompanied the description is the first known published illustration of a dinosaur bone.
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| First published illustration of a dinosaur bone. The Natural History of Oxfordshire. 1677. http://biodiversitylibrary.org/page/48062596. Digitized by Smithsonian Libraries. |
Plot first concluded that the bone belonged to a Roman war elephant, but later decided that it must instead represent the thighbone of a giant human like those described in the Bible. In 1763, Richard Brookes used Plot’s illustration of the thigh bone in his six-volume publication A System of Natural History. His reproduction of the illustration includes a caption that reads Scrotum Humanum, referencing the visual similarity between the bone and the human scrotum. Though the name is not considered valid today, its structure, following the Linnaean system of binomial nomenclature, has caused some to argue that it represents the first species name ever applied to an extinct dinosaur, because this thighbone does not, in fact, belong to a giant human, as Plot concluded. It belonged to a dinosaur, probably a Megalosaurus, although, since the specimen has since been lost, it’s impossible to know with certainty which species it belonged to.
Scrotum Humanum notwithstanding , Megalosaurus represents the first dinosaur genus to be described and validly named. In 1824, William Buckland gave the genus the name Megalosaurus in his article “Notice on the Megalosaurus or Great Fossil Lizard of Stonesfield,” describing it as an extinct giant reptile. The lithograph of the Megalosaurus jaw that accompanied the description was based on drawings done by Buckland’s wife, Mary Morland. Later in 1827, Gideon Mantell, in his The Geology of the southeast of England, assigned the type specimen its current valid binomial: Megalosaurus bucklandii.
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| Megalosaurus jaw and teeth. Transactions of the Geological Society. ser.2, v. 1 (1824). http://biodiversitylibrary.org/page/36238855. Digitized by: California Academy of Sciences. |
The carnivorous Megalosaurus, together with the herbivorous Iguanodon and armored Hylaeosaurus, were the three genera later used by Richard Owen to define Dinosauria.
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Grace Costantino served as the Outreach and Communication Manager for the Biodiversity Heritage Library from 2014 to 2021. In this capacity, she developed and managed BHL's communication strategy, oversaw social media initiatives, and engaged with the public to excite audiences about the wealth of biodiversity heritage available in BHL. Prior to her role as Outreach and Communication Manager, Grace served as the Digital Collections Librarian for Smithsonian Libraries and as the Program Manager for BHL.
Hi,
In your article fact or fiction about the mosasaur (I’m a cityguide in Maastricht, hence my interest) you describe mosasaur getting his name in 1822.
Yet in this article you write megalosaur was the first to be described as dinosaur. Has it just to do with the official namegiving of the Hoffmani part?
Is it true that findings like this started the evolution theory thinking in Europe, finalized by Charles Darwin?
Hi Jerome,
Thank you for your questions. To address the first question, scientifically, mosasaurus is not a dinosaur but an aquatic reptile (see https://www.nhm.ac.uk/discover/what-are-dinosaurs.html, section “Other Prehistoric Reptiles”). Therefore, Megalosaurus was the first validly named dinosaur from a scientific classification perspective.
As for your question on the history of the development of the theory of evolution, staff at the National Museum of Natural History (NMNH) could provide a more thorough answer. Visit https://naturalhistory.si.edu/contact-us for contact information at NMNH.