244 million years ago, the oceans were dominated by an array of sharp-toothed, terrifying sea monsters. One such beast is the Thalattoarchon – a name which translates to “lizard-eating sovereign of the sea.” That’s quite a title, and this ichthyosaur had the reputation to boot, crunching prey just as large – if not larger – than itself.

Measuring at least 8.6 metres in length (or about the size of a London bus), the finding of Thalattoarchon fossils revealed something pretty amazing about the resilience of marine ecosystems. Only 5 million years after the biggest extinction event in Earth’s history (the end-Permian extinction), this apex predator had made a return. Thankfully for divers, Thalattoarchon and fellow ichthyosaurs went extinct despite thriving for some 160 million years.