What are Ichthyosaurs?
Ichthyosaurs, whose name means “fish lizard” in Greek, were large marine reptiles that lived between 230 and 90 million years ago. They superficially resembled fish or dolphins. Ichthyosaurs shared the seas of Earth with sharks, fish, and other marine reptiles like plesiosaurs and pliosaurs. Ichthyosaurs were first described from fossil fragments dug up in 1699 in Wales. Ichthyosaurs evolved just 21 million years after the greatest mass extinction in history, and disappeared about 25 million years before the mass extinction that killed off the dinosaurs. Though ichthyosaurs are sometimes incorrectly called dinosaurs, they were not. The fish-like body structure of ichthyosaurs led biologist Stephen Jay Gould to call them his favorite example of parallel evolution. The evolution of ichthyosaurs into streamlined dolphin-like forms is made even more remarkable by the fact that they evolved from terrestrial reptiles without any body features to work with; not even so much as a small tail fi
