Earlier quoted context omitted.
Certainly, we see some some traits that arise independently in different populations in different places with similar traits and are preserved and develop in similar ways, but the fact that a feature that contributes to fitness arises uniquely in one place is far from surprising. I grant you all but a feature that contributes to fitness arises uniquely in one place is far from surprising . First, I'm not a biologist…
> it seems at least mildly surprising that we've never observed at least similarly structured creatures. Its not surprising that some survival-valuable features (especially when they fulfill a function for which there are other mechanisms) arise and are preserved and further developed only once, since them arising in a species in which they are survival-useful is a matter of chance, as is their preservation. So, its…
Indeed. In fact, what I find more surprising is that some non-trivial adaptations have developed more than once. Flight for instance evolved four separate times (bugs, birds, bats, and now-extinct pterosaurs all fly[flew], but none of them share a common ancestor that could also fly.) I find that simply remarkable. Really drives home the massive timescales that are involved.