I wonder how they figure the big D's trunk was shorter...

No, the feline is wild and being encountered in the wild as a threat to the human who encounters it, and the herd of pachyderms is being hunted.

The big stone monuments are an interesting tidbit for me. The time in the movie's title coincides with when one person I know of says the Sphinx was built (and thus, implicitly, some other things around it too). This is long before history & archeology would say any such construction was going on, but he bases his argument on the erosion of the cliff walls behind it; he says that they would have been a smooth vertical face that long ago but already been rough and eroded by the more recent time historians and archeologists give, and that the pattern of erosion is what you'd get if a significant amount of the erosion the cliffs have experienced was by rain instead of wind, which requires that the cutting have been done when the local climate was wetter than it's been recently. Of course, historians and archeologists say he's a quack, and I know he supports other quacky ideas (mainly that there was an advanced worldwide culture long before the most "ancient" local advanced civilizations we know of), but I know of nobody who refutes his geological claims, and geology seems to be something about which he's more honest/rational instead of sensational (for example, calling the square-looking stones under water near Japan natural instead of calling them the work of an extremely ancient advanced civilization).

However, even if he's right about advanced stone construction happening so early in Egypt, the movie still got it wrong by putting that in a desert setting instead of a green one...