* The aliens are apparently hermaphrodites. [[spoiler: Wikus's metamorphosis into a Prawn is a horrific and bloody experience; so imagine what that part of the transformation must have been like - actually, just don't. Blech.]]
* The black fluid essentially serves as the fuel source for the mothership's command module, now recall that Christopher and his son gathered the black fluid over 20 years and that the small drop we see them cultivate is the last bit they need to get the ship to fly them back home. Now recall that [[NiceJobBreakingItHero Wikus sprayed more than that on his face.]] Best case scenario, they have to drift to their home planet for the last leg of the journey. Worst case, [[FateWorseThanDeath the ship loses functionality in the depths of deep space...]]
* Wikus comes across as a huge asshole for hitting Christopher with a shovel and trying to abandon him and go home. Until you look closely at the scene with Wikus' wife being interviewed in her bedroom. On the top left corner of the mirror is a sonogram. Wikus is so desperate to get home because his wife is pregnant and he wants to be there for his child.