Why Did Ichthyosaurs Go Extinct?

Ichthyosaurs were one of the most successful lineages ever. These dolphin-looking marine reptiles of the Mesozoic Era evolved to occupy a vast range of niches: Some were massive apex predators hunting in the open ocean, others were small suction feeders swimming in shallow seas. All ichthyosaurs went extinct tens of millions of years before the dinosaurs were wiped out during the famous Cretaceous-Paleogene extinction event. But we still don’t know why.

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