* AdaptationDisplacement: Inspired by the book ''The World Without Us'' which, due to its success and also to perhaps because it was named one of ''Time'' Magazine's Books of the Year for 2007, suddenly made this subject very popular. The Magazine/NationalGeographic Channel also had a [[DuelingShows very similar show]] at the same time called ''Aftermath: Population Zero''.
* InferredHolocaust: Not just the humans, but the animals that are bound to die in our absence.
* NauseaFuel: "Last Supper" (Season 2, Episode 4) features a Fort Worth, Texas supermarket that was abandoned for several months in 1999 [[WayPastTheExpirationDate with all the food still inside it]], and goes into great detail about what happens when you leave an entire grocery store's worth of food sitting unattended in the summertime in Texas.[[note]]After complaints from neighbors over the smell, the supermarket was fumigated and stripped to the bare walls.[[/note]]