Eubrontes giganteus, for example, is there a mere 10, 000 years after the iridium anomaly.

ECONOMIST: The rise of the dinosaurs

Both an iridium anomaly and a fern spike appear in rocks at the end of the Triassic, too.

ECONOMIST: The rise of the dinosaurs

Dr Norman MacLeod, the keeper of palaeontology at the Natural History Museum, London, UK, told the BBC that the iridium anomaly could be attributed to other factors.

BBC: Impact led to dino rule