"Posted at AvP Outbreak on 30.09.2004 at 16:31:18
Thought you might be interested in this (rather long) post that I contributed to the IMDb many moons ago aimed at countering folks that criticised AvP claiming that it included too many incidences of breaking the Alien or Predator canon.
*** This post contains a lot of SPOILERS *** Predator Issues 1. The Predator’s vision is completely wrong! This was a major question and one of the questions that could only be answered by watching the movie after knowing the question

The simple answer is that the Predator vision in AvP is completely canon - for one, Anderson NEVER shows un-helmeted Predator vision (which, from Predator 1 and 2) we know is "thermal-like". I paid a lot of attention to this and in every scene that shows a Predator point-of-view (PoV), the Predator in question is wearing its helmet.
From the "slaughter house" scene in Predator 2, we also know that the Predator helmet has several modes, each seeming to visualize a different part of the electro-magnetic spectrum (let’s call them EM-modes). When the Predator cannot see the source of the noise (from the capture-team on the stairs), it switches between a number of different modes until it reaches UV-mode which picks up the beams from the black-lights carriied by the team.
Aliens showed that the Alien cannot be seen with IR (thermal) vision (when Dietrich looks straight at the Alien on the wall, but cannot see it). It therefore makes perfect sense that the EM-mode seen from the Predator’s PoV would be a modified mode that sees a different part of the spectrum in which Aliens are visible. In any case, AvP does not mess with the basic non-helmeted vision nor do anything but expand on the helmet modes.
2. Predator weapons don’t cloak! I’d suggest that people who suggest this go back and watch the scene in Predator 2 where the rest of the clan are re-cloaking. Several of the Predators are carrying different weapons, including spears, and it is very clear that the spears cloak with the Predator (honest!)
3. The Predators should have skinned opponents or collected trophy skulls This is questionable for several different reasons: The Predator’s in the first two movies only collect the skulls of worthy opponents (for example, Blain in Predator 1 and King Willie and Lambert in Predator 2), they certainly don’t do it for all their victims (the special forces team found by Dutch’s group in Predator 1 come to mind). Now the only Predator who survived for any period of time was Scar and the only human I remember him killing for certain is Weyland. I personally don’t think that he caused Scar enough of a problem to warrant trophy-taking. He did kill an Alien and he marked himself with it’s blood but I don’t personally think it caused him enough of a problem to collect its skull as a trophy - even so, he didn’t have enough time to do anything before he was face-hugged. This also screws with your memory, so maybe he just forgot when the Pyramid moved again and he left the chamber...
Skinning is a seperate issue and the Predators seem to delight in doing this to pretty much everyone. (Note: they only seem to do it to those who they themselves have beaten; e.g. King Willie’s men are hung and skinned in Predator 2 but the Columbian that they killed is not.) We did see the mining team strung up and we could assume that the Predators were in a bit of a hurry to get to the Pyramid thus the lack of skinning (or maybe they wanted to skin them somewhere warm?). Again, Weyland was the only human killed by Scar and it probably would have been good to see that the Predator had skinned and hung him (though, I guess that a hung-skinned human would push hard against the PG-13 rating).
4. Why is the Predator armour/helmet different? This was explained in the "Making of AvP" featurette. The Predators were hunting Aliens not humans and because of the extra threat Aliens pose (claws, teeth, tail, tongue, "acid blood", etc.) they wore body armour. Remember that in Predator 1 and 2, the Predators did not armour their chest area (there was just a string vest affair) so this was a new one. The armour could also provide insulation against the cold surface conditions.
5. It was stupid that two Predators were taken out so quickly Actually this makes a reasonable amount of sense after carefully watching the whole fight scene again. First, the Predators plans had been thrown into disarray with the unfortunate activation of the Pyramid mechanism and the sacrificial chamber. Their prime concern at this moment was the recovery of their shoulder-weapons and the two in question (one warrior and an acolyte) were distracted by the fight with the humans who’d stolen them.
The first Predator was intent on killing Woods so didn’t notice the Alien sneaking above him and spearing him with its tail. The Predator was basically dying from there on in and was simply given a coup de grace with its "head-bite"
The second (Celtic) was alerted by this and gave the Alien (Grid) a run for its money. Unfortunately, as has been seen in Predator 1 and 2, they can be very overconfident in themselves. The Predator was basically taken in the same way Harrigan finished off the Predator at the end of Predator 2... it assumed it had vanquished the enemy and was coming in, unprepared for attack, to finish it off only to pay the ultimate price for its inattention. I thought this fitted in well with what we know of the Predators so far.
6. How come the Alien can bite through a Predator helmet? They’re bullet-proof! Who says they are? Which scene in Predator 1 or 2 showed this? A bullet may have bounced off but it doesn’t mean that it’s bullet-PROOF, just bullet-RESISTANT. The force applied by the Alien tongue in such a small area could well punch through the helmet (after all, we already know that an Alien can punch through another Alien’s skull).
7. The Predator self-destruct bomb was far too large! There are two answers to this question. The first refers to Predator 2 where Keyes explicitly says that the bomb at the end of the first movie destroyed "300 city blocks" worth of rain forest - that’s a pretty big explosion (and Arnie only survived because they wanted him for a sequel - he really should’ve been toasted

)
The second answer involves attention to the "flash-back" scene in AvP. This shows that Predators are willing to nuke a civilization to stop the spread of Alien infestation (it shows that most of the population had been used as hosts - I think someone said there were supposed to be 14,000(?) Aliens in that shot). You would expect the self-destruct to be able to encompass the entire Pyramid if things went pear-shaped... which, of course, they did...
8. Why can’t the Predators see the Alien larva in Scar at the end? Good question, but again, it could involve over-confidence (which seems to be a very common Predator flaw). One answer from looking at the movie again is that the Predators at the end ARE wearing their helmets. Given that their normal vision is thermal-like, I guess you could assume that they would use a normal thermal EM-mode (replicating their own vision) when not hunting Aliens, it would be more comfortable?
9. What are Predators doing in the Antarctic? They only hunt in hot climes One canon rationale for this is a line in Predator 1 where the woman says that they only come in the "hottest summers". Some claim that Predator 2 actually explicitly says that hunt in the heat because of Keyes’ statement in that movie where he says "they’re drawn by heat and conflict". However, before that he mentions three places that they know the Predator hunted: Iwo Jima, Beirut and Cambodia. Beirut and Cambodia may have been hot - Iwo Jima, during the US offensive in WWII was cold and rainy... In addition, the Predator did not seem adversely affected by eating and then subsequently hunting in a very cool slaughterhouse...
Alien Issues 1. The Alien gestation period is far too short The biggest apparent flaw is unlikely actually to be a flaw but I’ve got to reconstruct a timeline of gestation periods from all four previous Alien movies that shows the gestation period varies widely between a full day (Alien) and a few hours or less (A:R). The simple answer is that the Alien Queen was "pumped full of hormones" which accelerated the Alien growth cycle. This is allegedly dealt with in a missing scene from the movie - it better be...
2. What’s with the mandibles on the chest-burster at the end? It is considered canonical that the Alien larva takes some of the host’s DNA to its own - this is vindicated by the "dog" or "ox" Alien in Alien 3. The combination of a Predator and Alien is known as a PredAlien and has been seen in several Predator sources (most of which aren’t canon though). This movie canonizes both the host DNA argument and the PredAlien finally.
3. And how could it survive in a dead host? Who says that Aliens can’t survive in dead hosts? This is an issue which has never been dealt with in an Alien movie... in every case where someone wants to be killed before the gestation of the chest-burster the body is somehow immolated destroying both the host and larva/chest-burster. In addition, the chest-burster decides on the best time to exit the host based on it’s perception of the outside environment and the activity levels of the host. It is assumed that they can hang around inside for as long as they want and, assuming the dead of the host, they would simply be hanging around for a bit until whatever killed the host leaves and it has a chance to come out and slither away...
4. Alien skulls are much less armoured than Predator helmets, aren’t they? Actually none of the movies suggest that an Alien skull is any less tough than a Predator helmet. The Alien exoskeleton is considered to be of variable strength with the skull being one of the toughest areas. There are only two of the movies that show an Alien skull being penetrated - Aliens and Alien: Resurrection.
In Aliens, the rounds used in the M41A1 are 10mm explosive-tipped armour-piercing rounds. We see an Alien skull blown apart when a smart gun puts a load of these into its skull from a range of about 3 ft. We also see Vasquez pump a load from a pistol into the skull from a range of ~1 inch and a shotgun blows apart an Alien skull from the inside (when it’s shoved into its mouth). None of these events indicate that the skulls are anything but very tough.
In Alien: Resurrection, there are two instances where Aliens are shot. The first is underwater when Johnno fires what looks like a 3-4cm+ explosive round and the second is when he’s on the ladder and firing down and a round penetrates the skull. The first situation shows that an Alien skull is not terribly resistant to a large calibre explosive round, which isn’t surprising. The second is more questionable, but I would point out that on examination, it looks and sounds like several rounds from the pistol hit the Alien skull and richochet away without damage before one hits it just right and penetrates.
5. How can Woods put her arm in an Alien skull to use it as a shield... what about the acid? Both Ash (in Alien) and Bishop (in Aliens) make it very clear that Alien blood oxidizes after death rendering it harmless (though I guess you wouldn’t want to drink it)
6. What’s with the super-sized Alien Queen? Two answers exist for this: (i) the Queen’s in Aliens and Alien: Resurrection are very young - in the Izzet"