It's an interesting bit that the characters point out. My guess is it will be an interesting / important plot point.
BUT it's not as strange as they make it sound (comments at the bottom here).
They've destroyed the mechs, so I'd imagine that at some point they'd study them. We learn that they at least study some of them as well as the children. Even if every one was blown up with C4 they would have to find "something" inside to indicate a human being in there. Even if skinned, there'd be bones and such.
My guess is that one group is enslaved to the other, and I too thought that maybe humans/kids played a role. Though I also wonder if they're trying to help/save the kids in some benevolent manner.
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Why it isn't as strange in real life as we think. Yes, as kids and in typical science fiction when we think "robot" we think bipedal human approximation. However in real life the direction we're taking autonomous robots is in another direction: less human and more insectoid and/or wheeled.
Humans are fine and all but you have to worry about keeping balance on rough terrain or damaging a single leg making it difficult to get anywhere. Meanwhile insects and things can continue without a leg and (so long as more long than tall) do not have to worry about balance issues. Balance, redundant legs, etc: nature evolved these things for reasons. Meanwhile wheeled-robots have more speed and are more energy efficient.
I'd seen some really strange layouts for robots: insects, worms/snakes, wheeled things, etc. All of which are much more mobile than those bipedal robots they showing from Japan.
The only real advantage the bipedal robot would have is potentially maneuvering through our built structures easier, like winding staircases and tight corridors.
Edited on 06/20/2011 7:21am