The terrifying physics of prehistoric sea monsters

Short Wave from NPR

Scott Detrow walks into the conversation thinking he knows what a mosasaur is. "Kind of like big sea dinosaurs," he offers. Regina Barber corrects him gently: they were not dinosaurs. They were giant marine lizards, apex predators of the late Cretaceous, swimming the same oceans while T. rex walked the earth. And yes, the one that leaps out of the water to snatch a shark in Jurassic World is a mosasaur — and between the first and second films, the animators actually updated its design to match new paleontological findings.

But the real news comes from a study in Current Biology. Paleontologist Kirsten Formoso at Rutgers University and her colleagues have figured out how fast these animals could move. The answer involves something they call a "slam start." Imagine a swimmer pushing off a pool wall, but scaled to the size of a city bus. Some mosasaurs with longer tails could reach about 15 miles per hour by curling their tails and lunging forward explosively. In one second, they could close 75 percent of the distance to their prey. Formoso and her team built physics models to reconstruct the animals' probable movement, using the closest living relatives — snakes and monitor lizards like the Komodo dragon — as a baseline for how muscles and skeletons might have worked. This is part of a broade