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1823: Mary Anning's Plesiosaur
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| Letter from Mary Anning to Sir Henry Bunbury illustrating her Plesiosaurus find. December 26th, 1823. Image courtesy of Show.me.uk. |
Note: Plesiosaurs are not "dinosaurs", however since their discovery is important to the history of paleontology, they are included within this series.
In December of 1823, Mary Anning, despite having little formal training in the areas of geology, biology, or paleontology, discovered, prepared, illustrated, and described the first nearly complete Plesiosaurus specimen. Mary Anning had long been dismissed by history as an amateur fossil hunter, however within the last few decades she is achieving the accolades for which she rightly deserves. Born in 1799 and growing up fossil hunting along the "Jurassic Coast" (as it is known now), more formally known as Lyme Regis, in the southwest English county of Dorset, Mary had long been known as a superior fossil hunter, despite rarely getting the scientific accolades she deserved at the time.
In 1811, Mary's older brother Joseph discovered the skull of an unknown animal. Upon continued searching and digging for the animal, Mary managed to unearth the entire 5.2 meter long skeleton of what turned out to be the first complete skeleton of an ichthyosaur. Prior to this discovery only fragments of ichthyosaur skeletons had been discovered and were thought to be some variety of fish vertebrae.
While that was a historical discovery, Mary's most notable discovery was yet to occur. In 1823, Mary Anning discovered a nearly complete specimen of a previously identified animal known as a plesiosaur. Having been previously described by by De la Beche & Conybeare (1821), Plesiosaurus was assumed to have been an aquatic tie between the already known Ichthyosaurus and modern day crocodiles. However this initial description was based on a flipper and some vertebrae. It wasn't until Mary's 1823 discovery of a nearly complete specimen, which included the very important skull, that a more complete understanding was possible. After discovering the fossil, Anning then prepped, illustrated, and described it in the hopes it would be purchased by someone. She wrote a letter to Sir Henry Bunbury, as pictured above, requesting the purchase of the fossil.
The letter read:
SirI have endeavoured in a rough sketch to give you some idea of what it is like. Sir, you understand me right in thinking that I said it was the supposed Plesiosaurus, but its remarkable long neck and small head shows that it does not in the least (?resemble) their (unclear, possibly another type of dinosaur?) in its analogy to the Ichthyosaurus. It is large and heavy, but one thing I may venture to assure you it is the first and only one discovered in Europe. Colonel Birch offered one hundred guineas for it unseen, but your letter came one days post before. I consider your claim to an answer prior to his. Should you like itthe price I ask for it is one hundred and ten pounds. One hundred guineas was my intended price, but if [I] take the same sum as Col B is offered he would think I had used him ill in not taking his money. - Sir I am gratefully obliged to both you Lady Bunbry for condescending to think of my favourite. He returned to Lyme at midnight quite well. I [am] also greatly obliged for your kind present of the game.Your most humble servantMary AnningLyme, December 26 1823P.S. Sir since I wrote the above I have received an order from the Duke of Buckingham if not sold to send him the specimen on his account. I hope you will not think me impertinent in requesting an answer by return of post I had forgot the Ichthyosaurus it is about four feete long although Not equal to C[aptain] Warrings it is not a bad specimen. The price is five pounds.
Based on the letter, and other similar letters, the fossil was purchased by the Duke of Buckingham. The fossil was then given to the geologist William Buckland, who then let Conybeare formally describe it, essentially omitting the work put in by Anning. The specimen, which is the holotype specimen (i.e., the specimen that the name is based on) of Plesiosaurus dolichodeirus (Conybeare 1824), would eventually be purchased by the British Museum of Natural History (specimen BMNH 22656). Mary Anning's plesiosaur can now be seen at the Natural History Museum, London (new specimen ID: NHMUK PV OR 22656)
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| Mary Anning's plesiosaur specimen as displayed at the Natural History Museum, London. Image by Adam S. Smith and courtesy of Plesiosauria.com. |
A little bit about plesiosaurs. Plesiosaurs were marine reptiles (note: NOT dinosaurs), that existed from the the Late Triassic (~203 million years ago) until the end Cretaceous extinction ~66 million years ago, the same one that wiped out the non-avian dinosaurs. The deposits that Mary discovered this specimen are known as the Blue Lias Formation, and are approximately 200 million years old (the unit spans the Late Triassic Rhaetian Age to the Early Jurassic Sinemurian Age). The rocks are interbedded limestones and shales that were deposited within the deeper offshore shelf waters. The lime mud is thought to have been deposited as a result of episodic storms.
References
Conybeare, W.D., 1824. XXI.—On the Discovery of an almost perfect Skeleton of the Plesiosaurus. Transactions of the Geological Society of London, 1(2), pp.381-389.
