This “Bayesian” method allowed for an unusually precise assessment of the likelihood that the Adamanian vertebrates in the ancient ecosystem went extinct dramatically and synchronously, as would be expected with an asteroid impact.
Previous research concluded the asteroid impact occurred 215.5 million years ago and the consequential climate change between three to five million years later.
The researchers demonstrated the extinctions happened over an extended period between 222 million years ago and 212 million years ago.
Some species of armoured archosaurs Typothorax and Paratypothorax, for instance, went extinct approximately six million years before the impact and 10 million years prior to the climate change.
The Acaenasuchus, Trilophosaurus and Calyptosuchus went extinct two to three million years before the impact.
Desmatosuchus and Smilosuchus species, on the other hand, died out two to three million years after the impact and during the very early stages of the climate change.