During the heavy rains, the Kim family’s half-basement apartment floods. This flooding causes the sewers to back up, which in turn sends human effluent spraying out of the turlet. This, quite literally, is a shitty movie detail.
Furthermore, as the eponymous title suggests, there was at least one parasite in said sewage.
If the petroleum deposits we’re digging up now are from all the plant and animal carcasses deposited millions of years ago, all the cemeteries we’re filling up now are going to be convenient petroleum deposits for when the cockroaches, or whatever, rule the world—assuming they require petroleum products, that is.
Every time Alex makes his special lasagna he mentions that he didn’t have real cheese. This is a subtle nod that cows are selfish jerks. They flat out refuse to acclimate to the vacuum of space. This is why Garfield won’t leave Earth, sasa ke.
The Belters, people born and raised in the asteroid belt, speak a creole language. Even with the subtitles on, I cannot understand what they’re saying. This is a subtle nod that not only am I an Earther, but so is the subtitle provider. And Google translate.