Chicxulub crater

• And that suggests their demise came suddenly, with the impact of a giant asteroid.
• The discovery of the 180km-wide Chixculub asteroid impact crater in Mexico suggested a sudden extinction of dinosaurs and other species, driven by the impact.
• But others have argued that a long, slow decline in dinosaur diversity contributed to their extinction.
• It’s not just that dinosaur fossils are so rare; the fossil record is also patchy.
• Because it’s such a huge landmass, Africa probably had far more dinosaur species than North America.

What we’ve found

• Dinosaurs may have swum out to islands searching for food, as deer and elephants do today, and some might have drowned.
• Other dinosaurs might have been washed out to sea by floods or storms, or drowned in rivers that carried them downstream to the ocean.
• And so, studying marine beds, and working over many years, we’ve slowly put together a picture of Africa’s last dinosaurs, bone by bone.
• It was smaller than Chenanisaurus, about five metres long – small by dinosaur standards, but large compared to modern predators.
• If so, that means dinosaurs were cut down in their prime; burning out rather than fading away.

What our findings show

• For over 100 million years, they evolved and diversified, producing a remarkable range of species: predators, herbivores, aquatic species, even flying forms, the birds.
• Then in a single, catastrophic moment, everything was wiped out in the months of darkness caused by dust and soot from the impact.

Nicholas R. Longrich does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.