Still, the human and reptilian couples are very similar, with one half ready to race ahead and the other digging in its heels. The difference is that the reptiles made their decision and took their first step. They've come to the surface to explore life above water. The humans are still deliberating. By the time Charlie and Nancy decide they're ready, Leslie and Sarah have made two steps -- from sea to land and from four legs to two. But having more options hasn't made life simpler; in fact, it's more complicated. Even evolution can move faster than two humans trying to make one decision. It must be all that time they spend talking.