Low Density Trees on Pandora

[ScottWashburn]

Watching the movie (again!) it occurs to me that the trees on Pandora seem awfully weak compared to Earthly trees. When the Thanator is chasing Jake it rips through small trees and the roots of bigger ones like they're made of balsa wood. later when Jake's fighting Quaritch in his AMP suit, the suit smashes right through logs that are easily two feet thick. Having just spent some time with a chain saw cutting up some fallen branches and big logs I know that a 2-foot length of good old Earth Oak isn't gonna break with just a measly AMP suit jumping on it. heck, a dozen of them could dance a jig on it without breaking I'm not saying that there's anything wrong with what we see in the movie, just that Pandoran trees aren't as strong as Earthly ones

[Sanjwale]

you have a point over there but remember that (I think) a ikran is very strong. and that it wouldn't be so simple as human/na'vi

[Wanderlust]

Lower gravity allows for less support need so weaker trees?

[Tarbtano]

It's a similar mechanism to why humans and plants grow weaker if they spend too much time in a low gravity environment. The gravity has less strain on the body, so the body halts the production of some reinforcing proteins for the muscles, bones, roots, and/or fibers to avoid wasting energy; creating a weaker body. This is why many Astronauts come home have trouble walking until their bodies can recover, because their legs have gotten so week with just weeks of time in space.

On a lower gravity environment like the fictional Pandora, or a hypothetical inhabited moon or small planet; life forms would evolve to be overall, weaker then their Terran counterparts; because their bodies would not waste energy to produce those extra proteins that make organic material denser and stronger. Due to the low gravity they may actually grow large, but again' have proportionally weaker bodies

PS: Not bashing anything, but this also means the Na'vi would be physically weaker then a human being, yet in the movie they are portrayed as roughly 2-3x stronger. Yet another case how Mr. Cameron is no scientist. but hey, this is fiction

[_Omaticaya_]

Dude you're totally right I think the reason everything is bigger generally is for the gravity, it's obvoius and scientifically correct. I mean, think of this, when we wake up in the morning, after about 6-8 hours of sleep, lying down, were like 3 cms or more taller, because the gravity is so strong in the night it kind of spreads us out in the night, then when we get up we shorten a little bit because of the pressure on our joints. So on Pandora, being less gravity, Na'vi grew taller, much taller, and also the trees and the animals grew bigger. So the weaker wood, most probably also a consequence of this, i also always think of the Thanator scene, because yes, we know he's like 3 times a lion, and got some big damn teeth and a LOT of force, but them huge roots? Nah, can't rip'em open like that, trees are tough