听力原文：W: Chris, when you are only in the fourth grade, you decided to dedicate your life to studying dinosaurs. Many forth-graders are fascinated with dinosaurs, but they grow up to be police officers, doctors or lawyers. What inspired you at such an early age to choose the study of dinosaurs as your life career. M: Actually it was a magazine, the September 7th, 1963 issue of Life magazine with dinosaurs on the cover. I still have the magazine today. I was visiting my grandfather's house and this magazine was sitting on the porch table. I opened it up and found not just fantastic pictures of dinosaurs, early reptiles and sea monster, but an article entitled the Pageant of Life. It was the story of how evolution works. It was wonderful. What got me was not just that dinosaurs were near and grotesque but that they were part of a much bigger history, a Greek historical story. So in the fourth grade, in 1964 I announced to my parents that I spend the rest of my life studying dinosaurs. And my parents nodded their heads and said 'That's nice, dear. It's a stage. You'll grow out of it.' W: But you didn't grow out of that stage, did you? M: No, I often wonder why most people cannot maintain their first love with nature, with dinosaurs or elephants or whales. You take any kid to a zoo or museum, and they'll be captivated by what they see. But that captivation dies away in high school. Why? Think part of it that the adult world tells kids, 'Hey, to like zoos or museums is childish thing. You shouldn't like them. Be interested in dating and cars or making money.' So they have lost their sense of wonder at nature. Nevertheless, you'll find a lot of adults enjoying taking their kids to the museums to look at dinosaurs. W: You're involved with many aspects of education and educational programs, and you lecture to groups of students all over the country. What are the most common questions the students ask you? M: They often ask about the Loch Ness monster in Scotland. They ask 'Is there any possibility of their still being a living dinosaur? No, for the following reason. You could hide one monster in Loch Ness, it's a deep enough lake. But you could not hide a breeding population of monsters. If you want to preserve a species, you need a minimum of 500 so that they can breed every generation and can have enough diversity in their genes so that they can keep on going. You can't hide 500 or 600 monsters because there'll always be death. Dead animals float to the surface of lakes or swamps. They get washed up onshore. And someone is going to find them. (47)