I think I was only talking about the evolution and intelligent design aspects of the Navi earlier in this thread.
What has been bugging me about this movie is that the mining company did it wrong. Whoever decided "Ground based invasion against natives!" might actually be a good idea for once failed at warfare forever.
They had the orbital advantage. THE orbital advantage. Not just the air superiority advantage, but the freaking orbital advantage. They weren't interested at all in the wildlife and trees, and what they were after was safely underground. Why wasn't scorched earth tactics and option? For MUCH cheaper than those mercs, a couple of satellites could have accomplished the job much quicker, cheaper, and more efficiently. You don't even need volatile weapons. You can literally huck rocks from space as a WMD thanks to the transfer of kinetic energy.
Chemical warfare could be really cheap and effective too. The planet was already inhospitable for us to start with.
I read too much Scifi.
That, and for the cost of those mercs, judging from the advanced state of the biotechnology we had in the movie, why wasn't biological warfare an option? Before those mercs can even be transported to the planet we could whip something up even in modern times.