In 1719, a stone slab used to reinforce the slope of a watering hole in Elston, Nottinghamshire, contained the partial skeleton of a creature that would eventually be recognized as the first plesiosaur. This specimen, later identified as Plesiosaurus dolichodeirus, was discovered by William Stukeley and brought to his attention by Robert Darwin, the great-grandfather of Charles Darwin. The bones were initially displayed in the local vicarage as the remains of a sinner drowned in the Great Flood, a testament to the limited understanding of fossils at the time. The stone plate, now housed in the Natural History Museum as specimen NHMUK PV R.1330, represents the earliest discovered more or less complete fossil reptile skeleton in a museum collection. This discovery marked the beginning of a journey to understand these ancient marine reptiles, which would eventually lead to the naming of the order Plesiosauria in 1835.
Naming The Sea Serpent
The formal recognition of plesiosaurs began in 1821 when William Conybeare and Henry Thomas De la Beche described a partial skeleton discovered in the collection of Colonel Thomas James Birch. They named the new genus Plesiosaurus, derived from the Ancient Greek plèsios, meaning closer to, and the Latinised saurus, meaning saurian. The name was intended to express that Plesiosaurus was more closely positioned to the Sauria, particularly the crocodile, than Ichthyosaurus, which had the form of a more lowly fish. In 1823, Mary Anning and her family uncovered an almost complete skeleton at Lyme Regis in Dorset, England, which was acquired by the Duke of Buckingham and later described by Conybeare on the 20th of February 1824. This specimen, now catalogued as NHMUK OR 22656, revealed the unique and bizarre build of the animals, leading to the provisional naming of a second species, Plesiosaurus giganteus, which was later assigned to the Pliosauroidea. The discovery of these fossils in the early nineteenth century sparked a renewed interest in paleontology and led to the naming of the order Plesiosauria by Henri Marie Ducrotay de Blainville in 1835.The Bone Wars
The rivalry between paleontologists Edward Drinker Cope and Othniel Charles Marsh, known as the Bone Wars, began with a plesiosaur discovery in 1867. Physician Theophilus Turner near Fort Wallace in Kansas uncovered a plesiosaur skeleton, which he donated to Cope. Cope attempted to reconstruct the animal on the assumption that the longer extremity of the vertebral column was the tail, the shorter one the neck. He soon noticed that the skeleton taking shape under his hands had some very special qualities: the neck vertebrae had chevrons and with the tail vertebrae the joint surfaces were orientated back to front. Excited, Cope concluded to have discovered an entirely new group of reptiles: the Streptosauria or Turned Saurians. However, when Marsh suggested that a simpler explanation would be that Cope had reversed the vertebral column relative to the body as a whole, Cope reacted indignantly. Leidy silently took the skull and placed it against the presumed last tail vertebra, to which it fitted perfectly: it was in fact the first neck vertebra, with still a piece of the rear skull attached to it. Mortified, Cope tried to destroy the entire edition of the textbook and, when this failed, immediately published an improved edition with a correct illustration but an identical date of publication. This affair became the cause of his rivalry with Marsh, who later claimed that Cope had been his bitter enemy. Both Cope and Marsh in their rivalry named many plesiosaur genera and species, most of which are today considered invalid.