Nobody knows exactly why dinosaurs went extinct but scientists are considering and studying a few main ideas.
One idea is that dinosaurs were no longer able to evolve. Throughout time, all living creatures have had to adapt to circumstances such as weather, availability of foods, and predators! If dinosaurs were no longer able to adapt to changes, it might have caused them not to survive!
Other ideas have to do with occurrences that might have changed the dinosaurs’ living conditions. One good possibility is that a meteor crashed into Earth. A meteor is like a rock from outer-space which lands on Earth. Scientists have evidence which points towards a very big meteor that may have crashed into Earth and caused a lot of dust. The dust might have made the air difficult to breathe, or it may have blocked out the light of the sun for so long that the plants died and the dinos were left with nothing to eat! Other evidence shows the possibility that a volcano (or many volcanoes) erupted and caused changes in the weather or particles in the air that the dinosaurs couldn’t live with!
Have you learned about any other theories??