So, they trained a gorilla to use sign language and built a machine to convert that to English. Fair enough. But then that sign language can be used to talk to wild gorillas? And it is the taught language because it simultaneously converts to English. So either the sign language was identical to natural gorilla communication, or someone taught those evil wild gorillas the sign language.
"SIT!" You get a bunch of creatures, breed them for (among other things) following human instructions, and they get understandably confused when something like them, or rather something like a generally nonconfrontational version of themselves, starts yelling at them in Squishy Pink Boss-man Language. It shows earlier that trying to get the gorillas to communicate with Amy without her teaching them first through gorillaspeak is ridiculous, when the regular gorillas are simply weirded out by Amy waving her hands and emitting odd noises. That doesn't explain why they still had the training ingrained into them so long after "Teachers" had all been killed.
Coco and Nim Chimpsky (a gorilla and a chimpanzee, respectively) did teach other apes the sign language they were told by humans at some point, so it's somewhat understandable that gorillas bred to follow orders from humans were the smartest of their kind and still passed the language they were originally taught by humans to their descendants long after the humans had disappeared. Why was that ancient African sign language so close to American Sign Language is still a very good question, though.
Why was the temple falling apart all of a sudden when the explorers arrived? I could get the lava flow later on, if the Super-Diamond refracto-powered laser had chopped up the ground, but I hadn't seen them do anything more than walk around early on, and the crumbling had started before they fired a single shot. For that matter, saying that the gorillas know what to do. If there hadn't been a flow like that since the temple was built, they wouldn;t know what to do. And thatHeadscratchers.
This is one of those little plot holes that appear when you change the original source material. In the novel, the eruption was triggered when Karen dynamitated a large area where she was expecting to find diamonds - she was the Corrupt Corporate Executive in the original story and a very unlikable character. They changed completely Karen's personality for the movie adaptation and as a result this incident had to be dropped because it did no longer make sense. Instead, they added an early line by Travis where he says that they've been monitoring the zone via satellite and that the hole area is about to blow up so they must act fast. Presumably, as per the movie verse, there have been quite a few earthquakes and eruptions around Zinj in recent times and the fact this one is so timely and so destructive is meant to be a pure coincidence. The characters might have considered the situation to not be as bad at first, hence their opinion that the gorillas might know what to do since they have survived all those previous quakes and eruptions.
It's not a plothole. It's specifically mentioned in the movie that the area is undergoing volcanic activity and is unstable. You just weren't paying attention.
Alright, not a plot hole but still a really Contrived Coincidence. The ancient city presumably survived thousands of eruptions during its long history of being sit near a volcano, but as soon as the movie characters arrive it is destroyed by the biggest eruption ever.
All writing works on contrived coincidence. "Oh, the diamonds we need just so happen to be in the one spot that's populated by horrific man-slaughtering ape-things!" At that point you're basically complaining that there's a plot and things happen.
How many expendable black assistants did they HAVE?
In Africa, it's pretty trivial to hire entire companies of men and firepower, especially with the resources an American multimillion dollar communications company can bring to bear.
Really, that explanation could have just ended after "It's Africa."
How the hell did Richard die? It's too dark to get a good look at his wounds, and it just looks like he had a freak-out that somehow resulted in him being covered in blood.
There's some indication that he's got a load of internal injuries and he's just barely hanging on as it is. Then he sees Amy, freaks the hell out, and between the thrashing and the screaming he finishes tearing up his insides.
Internal injuries, exposure, shock, and then a sudden burst of intense terror which would have sent his heartrate and blood pressure skyrocketing. He had the perfect conditions for essentially dying of fright, yeah.
Uh, OP here. I was talking about Richard. You know, Peter's assistant who died after the group discovered the Temple, not the guy who died from shock after seeing Amy? Anyway, after rewatching the film, I do see that he did get ripped up pretty badly, but now that brings me to another question: As we see later on with Homloka, Kahega and the remaining Porters, these Gorillas tend to beat their victims to death and/or rip them apart, but Richard, while fatally wounded, was able to get away for a bit before dying. How was he able to get away from the Gorillas before he died, and how was he able to run with those fatal injurys?
They were toying with him for sadistic kicks and adrenaline, respectively.