Can the Yautja possibly have a venomous bite . . .? Most animals with fangs do. And a paralyzing neurotoxic venom would allow Yautja to kill and eat prey that is much larger than they are, with just a single bite. Seems a good adaptation for a predatory animal with a high metabolism, active lifestyle, and hence large appetite (as the Yautja seem to have). So to me, that's the explanation that seems to make the most biological sense.
Now there's a thought. But here's something that I've been thinking... Hope yer ready for a biology lesson! There's in fact a reptile alive on OUR planet that has a venomous bite, without any venom, causing massive blood poisoning just because of its diet and is an integral part of how they hunt. And unless our dear friends, the Yautja, spend all morning brushing their teeth (Doubtful since in the book AVP: Hunter's planet, Machiko mentions that they have VERY poor hygiene), may very well have the same ability. The animal I'm speaking of is the komodo dragon. Unlike most other reptiles, these
predators are big enough to take down some serious prey. Also, they will eat pretty much anything they can get their claws on. Invertebrates, other reptiles (including smaller Komodo dragons), birds, bird eggs, small mammals, monkeys, wild boar, goats, deer, horses, water buffalo, and yes; even humans.
Due to this type of diet, researchers at the University of Texas found more than 55 different strains of bacteria growing in the mouths of different komodo dragons. What this means is one bite and someone or something that doesn't get immediate medical attention will die. True, it may take up to a for the prey animal to die, but that brings us to the next part. These reptiles will spend that time
hunting the animal they bit. Doesn't matter how far the animal goes, the dragon that bit it will eventually hunt it down and finish the job.
Now, let's look at the Yautja. In Predator 2, they say that he eats the beef, obviously raw. And in AVP: Hunter's Planet, Machiko says that they ate all their food raw. Now, picture them doing that on every planet they visit. Who knows what kind of bacteria they have growing inside them?
Now, that we're on this page, here's another thought. What if the Yautja got their start this way? Look at this: These dragons at this point in evolution not only wait and ambush prey, but they inflict a mortal wound on the prey and then track the prey for miles. Can you imagine what kind of being these things have the potential of becoming down the road? (If they don't become extinct, of course) Hell, they could potentially become something like a real life Yautja.
Sorry if it seemed like I got off topic, but I thought it was relevant to what was said...