The extinction of the dinosaurs, 66 million years ago, is one of the great unsolved mysteries of science. Although a sudden and catastrophic event (an asteroid impact, intense volcanic activity, or both) has been widely recognised as the most likely killing mechanism, some authors contend that environmental changes in the Late Cretaceous were responsible for a long-term decline in the number of dinosaur species. A novel approach, merging fossils, big data and machine learning, may help untangle the conundrum.