I realize that this is pure speculation (unless there is actually obscure in game dialogue backing it up), but did there used to be oceans on Pandora?
Maybe the days used to be shorter and / or colder and the rotation of the planet was altered by a massive asteroid or other foreign space body collision and its pitch / spin was thrown off, leading to hotter, longer days and the gradual evaporation of the oceans?
I ask because Crawmerax and Larval Crab Worms (Crab) sure do look like giant lobsters or other similar Arthropods.
Also, the giant deserts of Pandora sure do seem like massive dried up ocean beds and maybe some of those GIANT SKELETONS we see looking so cool all over the place could be the only remains of ancient ocean Leviathans?
I mean, the Deep Fathoms area in the Knoxx DLC is a ridiculously oceanic name!
What do you all think?