Although every main character is a non-human animal, humans have been mentioned several times throughout the series. In addition, photographs and paintings of humans are shown frequently. The following are various instances in which humans are mentioned.
- In the episode "Mission to Mars", Uniqua asks, "Who flew all this way...to explore a new planet for the whole human race?" while singing the song "Astronauts Never Give Up".
- In the episode "Cops and Robots", Pablo mentions a "human boy" while singing the song "I Feel Good".
- In the episode "Garbage Trek", Tasha tells her crew that they have "more trash experience than the whole human race" while singing the song "You Can Do It".