Again, i'll illustrate the point that the predators are a so called 'civilized' race, the aliens are born from death, the have only two objectives in life - to kill and to breed.
More points surround the aliens abilities to be able to survive in any environment without the aid of technology - take the preds into the cold without their thermal netting and they'd die of exposure.
EERRMM, reality check here - predators, even with weapons - STILL got their skulls cracked open. Without weapons, the predators would have zero chance of survival.
but what if the sky was fild with metors raining apone the battal feld and the aliens were spuing from every were like a plage sent from the bouls of hell muhahahahahahahahaha