250 million years ago, small terrestrial reptiles transitioned to the oceans, evolving into the giant ichthyosaur Cymbospondylus youngorum in a few million years due to a global ecological catastrophe, the Great Dying. Following the event, post-apocalyptic oceans allowed ichthyosaurs to rapidly evolve and thrive, exhibiting exceptional growth within a short span of 3 million years before facing extinction by the Late Cretaceous.
Insights
Small terrestrial reptiles transitioned to the oceans around 250 million years ago, evolving rapidly into giant ichthyosaurs like Cymbospondylus youngorum within a few million years, marking the start of an era of ocean giants.
The rise and evolution of giant ichthyosaurs were catalyzed by the global ecological catastrophe known as the Great Dying, which created post-apocalyptic oceans that allowed ichthyosaurs to thrive due to abundant prey, showcasing exceptional growth within a short span of 3 million years before facing extinction during the Triassic-Jurassic extinction event.