Dinosaurs arrived between 243 and 233 million years ago. Some evolved to gigantic sizes — such as the massive Dreadnoughtus (Dred-NAW-tus) schrani, which was larger than a 25-meter (82-foot) swimming pool. Others were just the size of pigeons or ducks.
Abundant fossil bones, teeth, trackways, and other solid proof have shown that Earth was the area of the dinosaurs for at least 230 million years. But so far, not a single trace of dinosaur remains has been discovered in rocks younger than about 66 million years. One of the most popular theories for the death of the dinosaurs is the Alvarez hypothesis, named after the father-and-son duo Luis and Walter Alvarez. In 1980, these two scientists introduced the idea that a meteor the size of a mountain crashed into Earth 66 million years ago, filling the atmosphere with gas, dust, and debris that drastically changed the climate.
Here you'll see the birth of a Velociraptor in Universal Studios Singapore; this was in 2019: