50 free Dinosaur Extinction trivia questions with answers — science & nature quiz, new questions added Aug 2026.
This dinosaur extinction trivia quiz covers the mass extinction of 66 million years ago, from the thin clay layer that gave the game away to the crater under the Yucatán. The easy questions are the ones any dinosaur fan should get: roughly when it happened, what most scientists think caused it, which peninsula hides the crater, and which living animals are the last dinosaurs. Then it gets tougher: the metal that is rare in Earth's crust but common in asteroids, the father-and-son team who spotted it in 1980, the oil geophysicist who found the crater a decade before anyone believed him, the shocked quartz and spherules, why crocodiles lived while T. rex died, the ammonites that never came back, the fern spike, the Deccan Traps debate, the North Dakota site that may record the first hours after impact, and how long it took mammals to reach 50 kilos. Every answer was checked against encyclopaedia entries on the Cretaceous-Paleogene extinction, the Chicxulub crater, the Alvarez hypothesis and the Deccan Traps before publishing, and the supporting sentence is stored with each question. If you enjoy this one, try our dinosaurs, Jurassic and Triassic quizzes next.
30 of 50 questions with answers and explanations. Play the quiz
Q 01Roughly how many years ago did the extinction that wiped out the non-avian dinosaurs occur?
66 million
It ended the Cretaceous and the Mesozoic and opened the Cenozoic era.
Q 02What proportion of plant and animal species on Earth are estimated to have died in the K-Pg extinction?
About three-quarters
Marine fossils suggest 75% or more of species vanished.
Q 03By what earlier name was the K-Pg mass extinction commonly known?
The K-T (Cretaceous-Tertiary)
'Tertiary' was dropped as a formal period name in favour of Paleogene.
Q 04Which metal, more common in asteroids than in Earth's crust, is unusually abundant in the K-Pg clay?
Iridium
The Alvarez team found it at 20 to 160 times normal levels in the sections they first studied.
Q 05Which father-and-son team proposed in 1980 that an asteroid impact killed the dinosaurs?
Luis and Walter Alvarez
Luis was a Nobel-winning physicist and Walter a geologist; chemists Frank Asaro and Helen Michel co-authored the study.
Q 06Which Dutch palaeontologist independently proposed the impact idea shortly after the Alvarez team?
Jan Smit
The impact site was still unknown when the hypothesis was published.
Q 07How wide was the asteroid thought to have caused the extinction?
10 to 15 km
It struck around 66.043 million years ago and dug a transient cavity 100 km wide and 30 km deep.
Q 08On which peninsula does the Chicxulub crater lie?
The Yucatán, Mexico
The crater is about 180 km across, roughly the size the Alvarez team had calculated.
Q 09What is the approximate diameter of the Chicxulub crater?
180 km
It is oval, with a peak ring that was drilled in 2016.
Q 10The Chicxulub crater was first noticed in the late 1970s by geophysicists looking for what?
Petroleum
Antonio Camargo and Glen Penfield could not prove it was a crater and Penfield gave up until the 1990s.
Q 11What surface feature, visible in satellite images, traces a circle matching the buried crater rim?
Cenotes (sinkholes)
The cenotes are thought to result from subsidence around the weakened crater wall.
Q 12What kind of object is the Chicxulub impactor now generally believed to have been?
A C-type asteroid
Its composition best matches carbonaceous chondrites of the CV, CO and CR groups.
Q 13A 2021 study estimated the impactor arrived at what speed and angle?
20 km/s at 45-60 degrees, from the northeast
Q 21Why are crocodilians thought to have survived while non-avian dinosaurs perished?
They can scavenge and go months without food
Their young are small, grow slowly and eat invertebrates and carrion for their first years.
Q 22Which group of dinosaurs survived the extinction and radiated into today's species?
Birds
Only a few ground and water fowl made it through, likely helped by the ability to dive, swim or shelter.
Q 23Which flying reptiles were wiped out entirely at the K-Pg boundary?
Pterosaurs
Two families, Azhdarchidae and Nyctosauridae, were still around in the Maastrichtian.
Winds near the blast exceeded 1,000 km/h.
Q 14What did the 2016 drilling into Chicxulub's peak ring find surprisingly little of?
Gypsum
The sulfate rock had vaporised into aerosols, prolonging the climate damage; the ring held granite flung up from deep in the crust.
Q 15What is the main mechanism by which the Chicxulub strike is thought to have caused mass extinction?
A long winter that halted photosynthesis
Dust blocked sunlight for up to a year; soot and fine silicate dust deepened the cooling.
Q 16Tiny spherules found in the boundary clay formed from what?
Droplets of molten rock from the impact
Microtektites matching Chicxulub have even been found inside amber at the Tanis site.
Q 17Which volcanic province in India is the leading rival or contributing explanation for the extinction?
The Deccan Traps
Gerta Keller has championed volcanism; a 2020 climate-modelling study favoured the asteroid.
Q 18Roughly how thick are the layered flood basalts of India's great volcanic province?
More than 2 km
They cover about 500,000 square kilometres of west-central India with a volume of a million cubic kilometres.
Q 19Which palaeontologist is the leading critic of the impact hypothesis, favouring Deccan volcanism?
Gerta Keller
She argues for a more gradual extinction driven by eruptions.
Q 20Most tetrapods above what weight died in the extinction, cold-blooded species excepted?
25 kg
Endothermic animals of any size needed far more food than ectotherms during the food-chain collapse.
Q 24Which giant marine reptiles that preyed on shelled cephalopods went extinct in the K-Pg event?
Mosasaurs
Ichthyosaurs had already vanished tens of millions of years earlier; plesiosaurs also died out at the boundary.
Q 25Which coiled-shelled cephalopods became extinct at the boundary while their nautiloid cousins survived?
Ammonites
Nautiloids laid few large eggs; ammonites relied on masses of planktonic larvae, which the collapse destroyed.
Q 26Which reef-building clams became extinct at the K-Pg boundary?
Rudists
Inoceramids, giant relatives of scallops, also died out, though their decline had begun earlier.
Q 27What percentage of colonial coral species, dwellers of warm shallow water, went extinct?
About 98%
Solitary deep-water corals, not dependent on photosynthetic algae, fared far better.
Q 28Which kinds of animals survived best on land, feeding on insects, worms and snails?
Omnivores, insectivores and scavengers
Neither strictly herbivorous nor strictly carnivorous mammals seem to have survived.
Q 29What size were the mammals that survived the extinction, generally?
About rat-sized
Within about 700,000 years some mammals had reached 50 kilos, a hundredfold increase.
Q 30Which mammal group suffered the heaviest losses at the K-Pg event?
Metatherians (marsupial relatives)
They largely disappeared from North America; eutherians recovered quickest.