Especially towards the middle where it talks about chewing and the skull, mouth and teeth getting smaller (and bones getting thinner.) This sort of struck me oddly with a little interesting thought I had years ago. This was something that just popped in my head and made for an interesting and twisted possibility.

As those of you may have read in the Religion forum, I'm one of those "Show me the money!" type people. I like to see proof of stuff or at least like to know I can easily seek out proof so I'm not a believer of this phenomenon but it does have a small degree of shallow interest from a sci-fi perspective. I'm talking about aliens. Specifically those little thin grey ones. Should they exist, what if they're us? After eons of evolution and genetic engineering. At some point they've screwed up and doomed themselves to extinction (or something along those lines.) So they come back to various places in time to take genetic samples for experiments to add some genetic diversity back into themselves, maybe through the breeding of hybrids to have the best of both "species." This type of activity doesn't really mess with the timeline to any significance.

This was even before I read W. A. Harbinson's Projekt Saucer books which has some degree of parallelism (human aliens) except for the time travel stuff. I've always thought those books would make for an interesting multi-year TV mini-series.