Ichthyosaur was one of many marine reptiles that ruled the oceans during the Mesozoic era. This fossil is from the late Jurassic, it is 140 million years old, and formed part of the creature’s spinal column. Ichthyosaurs first appeared during the Triassic, and became extinct in the late Cretaceous, but before the dinosaurs did.

Ichthyosaurs are an excellent example of parallel evolution, they were originally land reptiles but then evolved to go back in the water. They then evolved to match the shape of dolphins, which evolved from mammals well over 100 million years later.