一谈到物种灭绝,大家首先想到的大概就是恐龙的灭绝。恐龙称霸地球约1亿6千万年之久,却在6500万年前神秘消失。关于恐龙灭绝的原因,科学家有种种猜想,比如小行星撞地球、火山大爆发、地壳造山运动、气候剧变等,目前尚无定论。远古时候发生的事,科学家还在不断地发掘证据以证实他们的猜想。但近代一些动物的灭绝,原因就明 When it comes to the extinction of species, what people think of first is probably the extinction of dinosaurs. Dinosaurs dominate the earth about 160 million years ago, mysteriously disappeared 65 million years ago. Scientists have all kinds of conjectures about the extinction of dinosaurs, such as the asteroid crashing into the earth, the volcanic explosion, the crustal orogeny, the drastic climate change and so on. There is no conclusion yet. What happened in ancient times, scientists are constantly digging evidence to confirm their conjecture. However, the extinction of some modern animals, the reason is clear