How flexible was the neck of Elasmosaurus and other Plesiosaurs?
Elasmosaurids, with anywhere from 32 to 76 cervical vertebrae would most likely have had necks ranging from “very flexible” to “insanely flexible.” Of course factoring for the fact that these are bones and not cartilage.
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Plesiosaurs in general though have much more diversity in their neck lengths, vertebrae counts, and thus flexibility, so within that order it’s really down to particular families or genus.
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Liopleurodon, for example, is also a Plesiosaur but members of their family (Pliosauridae) tend to have much shorter and less flexible necks than their crazy Elasmosaurid relatives.














