DinoFact
Why Did the Dinosaurs Go Extinct?
Facts about the end of the dinosaurs — the giant asteroid, the great extinction, and why birds survived.
- The asteroid left a giant crater near Mexico.
- That means dinosaurs never fully went extinct.
- Dust from the impact may have blocked out the sun.
- All the big dinosaurs died out a very long time ago.
- New kinds of dinosaurs appeared as old ones died out.
- The Chicxulub crater is more than 150 kilometres wide.
- Non-bird dinosaurs died out about 66 million years ago.
- Birds were the only dinosaurs to survive the extinction.
- A huge asteroid struck Earth around the time dinosaurs died out.
- Birds were the only dinosaur lineage to survive the mass extinction.
- Gideon Mantell helped recognise Iguanodon as a giant extinct reptile.
- Shocked quartz and tektites at the boundary support a major impact event.
- The end-Triassic extinction cleared niches that dinosaurs rapidly filled.
- The extinction event is known as the Cretaceous-Paleogene (K-Pg) boundary.
- Post-impact wildfires, darkness and cooling collapsed food chains worldwide.
- The asteroid struck near present-day Chicxulub on Mexico's Yucatán Peninsula.
- The extinction of non-avian dinosaurs is dated to about 66 million years ago.
- Pachycephalosaur domes show injuries consistent with high-impact head contact.
- The Chicxulub impactor is estimated at roughly 10 to 15 kilometres in diameter.
- Only dinosaurs of the bird lineage survived the end-Cretaceous mass extinction.
- The end-Cretaceous extinction wiped out about three-quarters of Earth's species.
- The Chicxulub impact released energy far exceeding all nuclear weapons combined.
- Dinosaurs rose to dominance after an extinction event at the end of the Triassic.
- Trackway spacing lets scientists estimate the speed and gait of extinct dinosaurs.
- The buried Chicxulub crater beneath the Yucatan Peninsula spans about 180 kilometres.
- Tsunamis, wildfires and an impact winter followed the end-Cretaceous asteroid strike.
- Birds, crocodilians, turtles and many mammals survived the end-Cretaceous extinction.
- The impact threw debris into the atmosphere, blocking sunlight and cooling the planet.
- The bird lineage that survived the end-Cretaceous extinction was beaked and toothless.
- A thin global layer of iridium-rich clay marks the extinction event in the rock record.
- The Cretaceous-Paleogene extinction removed roughly three-quarters of species on Earth.
- Gideon Mantell's work on Iguanodon helped establish dinosaurs as giant extinct reptiles.
- Iridium is rare on Earth's surface but common in asteroids, supporting the impact theory.
- Dinosaurs became ecologically dominant only after end-Triassic extinctions removed rivals.
- Massive volcanic eruptions in the Deccan Traps in India may have contributed to the extinction.
- Non-avian dinosaurs went extinct about 66 million years ago at the end of the Cretaceous Period.
- Deccan Traps volcanism in India released vast volumes of gas around the end-Cretaceous extinction.
- Iridium, rare in Earth's crust but common in asteroids, spikes at the Cretaceous-Paleogene boundary.
- A massive asteroid impact about 66 million years ago is the leading cause of the dinosaur extinction.
- Enantiornithes were a diverse group of Mesozoic birds that died out at the Cretaceous-Paleogene boundary.
- The Signor-Lipps effect describes how patchy sampling can smear out a sudden extinction in the fossil record.
- Most dinosaurs lived nowhere near humans; non-avian dinosaurs died out about 66 million years before people existed.
- Teleocrater means 'complete basin'. It was a Middle Triassic carnivore from Tanzania — an early member of the dinosaur line.