A new study from the University of Maryland traces a 120-million-year-old “super-eruption” to its source, offering new insights into Earth’s complex geological history.

Imagine a crocodile built like a greyhound — that’s a sebecid. Standing tall, with some species reaching 20 feet in length, they dominated South American landscapes after the extinction of dinosaurs until about 11 million years ago. Or at least, that’s what paleontologists thought. A new study shows the Caribbean Islands were a refuge for the last sebecid populations at least 5 million years after they went extinct everywhere else.