We now know this transition is the one time that dinosaurs actually went below that body size -- we're going to see where they began in a minute -- and it is the one time that they rapidly invaded all the habitats I just told you that dinosaurs weren't in.
我们现在知道这个转变 是在恐龙逐渐变小的过程中 开始的。 接下去我们要讨论它们是从哪里开始的。 正是那个时期，它们迅速地 繁衍生息。 我刚才说过恐龙们是不去水中生活的。