context: The Cretaceous Mass Extinction occurred on Earth 65.5 million years ago. At that time, dinosaurs and many terrestrial and marine animals became extinct and chalk-top animals disappeared. Large species were the most affected [1], the small ones survived better. Homemade ammonites disappeared completely from the seas. Small reptiles, mammals and birds survived.
question: When did Dinosaurs Extinct?
answers.text: 65.5 million years ago