I don't understand.

When people hear about the extinction of the dinosaurs, many probably think of an “asteroid impact,” but it seems that while that hypothesis is considered the most likely, the actual cause isn’t definitively known. In addition to the “asteroid impact,” there’s also the “volcanic activity” hypothesis, which is likewise regarded as a strong contender.

Quetzalcoatlus

Quetzalcoatlus is said to have had a total length of over about 10 meters. Although it was one of the largest pterosaurs, it is thought that it may not have been able to fly long distances. Its name comes from Quetzalcoatl, the serpentine deity from Aztec mythology in Mexico.

Biting force

The biting force of Tyrannosaurus, often said to be the strongest in the dinosaur world, is said to reach up to 6 tons—powerful enough to crush even a car. Terrifying, isn’t it? However, young Tyrannosauruses had slender jaws, so their bite force wasn’t that strong.

Iguanodon

Everyone’s name ends with “-don,” so it was confusing, wasn’t it? But if you know Iguanodon, you probably realized it didn’t have wings. Iguanodon is a dinosaur discovered in 1821 by Gideon Mantell in the UK. It was the first dinosaur ever studied.

Moshiryū

Moshiryū is a dinosaur discovered in 1978 in Moshi, Iwaizumi Town, Iwate Prefecture. It has no scientific name; “Moshiryū” is a popular name. Until the discovery of Moshiryū’s fossils, it was believed that dinosaurs did not live in Japan, and the find later became a catalyst for subsequent discoveries of dinosaur fossils in the country.

lizard

“Saurus” is a Greek word meaning “lizard.” In fact, dinosaurs are actually in the lizard family—surprising, right? Also, the “don” in Pteranodon means “tooth,” and the “ops” in Triceratops is said to mean “face.”

head

Pachycephalosaurus, with its dome-shaped skull, is a dinosaur popular with children for its unique appearance. Because its skull is very thick, it is often said to have been good at head-butting; however, some argue that absorbing impacts would have been difficult, suggesting it may not have head-butted after all.

bird

They may not look much like dinosaurs, but birds are said to be their descendants. They were even featured as a theme in the movie Doraemon: Nobita’s New Dinosaur. Most dinosaurs went extinct about 66 million years ago, but the ones that survived are believed to be birds.

Spinosaurus

Speaking of Spinosaurus, it’s a carnivorous dinosaur that rivals Tyrannosaurus in popularity. Based on its high bone density, Spinosaurus is thought to have spent time in the water. Its predatory style is said to be similar to that of crocodiles, which float in the water and wait for prey.

stone

You might be surprised and think, “Were they eating stones?” Of course, they weren’t eating stones as food; it’s believed they swallowed them as gastroliths to aid digestion. Many bird species are also known to have gastroliths.