In the distant future (or at least 20 Minutes into the Future), humanity has declined, and animals (whether all of them, or a few certain kinds) become the new dominant species.
Here, the humans might be extinct and animals now roam the world freely; there might be scenes of them living on manmade living places if any of them existed at all. Or, there might be only a few humans left, either scattered away or confined to a single location, and they've been regressed (in various ways) that they can't form a modern-like society anymore; they're no longer the dominant species.
Sometimes, the animals might be, or become, Funny Animals or Petting Zoo People (there may or may not be an in-universe "evolution" happening to them); they have become the new "man". Furthering in this direction, the humanoid animals may even see the humans (if there are any) as "animals", either as a Human Pet, human cattle, etc.
Plots involving this setting might be about how animals live now that they're the dominant species, or they may focus on the few humans who tried to survive in the "new world" full of animals.
Cockroaches Will Rule the Earth is a subtrope.
See also Uplifted Animal, which is how the animals become smarter.
- In Kamandi, the Last Boy on Earth, a great disaster has killed off nearly all humans, with the few survivors lacking intelligence, and in the meantime, races of humanoid animals have risen up to take the humans' place on the food chain.
- In My Cage, humans are long extinct and the world is populated by civilized anthropomorphic animals of various species. Although the characters are aware humans once existed, the strip's focus on workplace humour means the reason for their extinction never comes up.
- Isaac Asimov's short story "No Connection" takes place on an Earth where humanity went extinct. America is populated by a peaceful bear descended race. The story ends with them expecting a conflict with ape descended aggressors from Eurasia.
- In William Tenn's "Null-P", dogs take over the Earth. Humans still exist, but they have given up civilization and it isn't even clear if they are sapient. They are adopted as pets by the dogs and later go effectively extinct.
- David Macaulay's picture book Baaa has sheep gain sentience and take over the world after mankind dies out. Their society quickly develops a lot of the same problems that drove human society extinct, with overpopulation, poverty, and a severe food shortage. Fortunately, the sheep leaders develop a new food product called "Baaa" that conveniently solves all three of those problems at once... Eventually this drives the sheep extinct as well.
- In Red Dwarf, while Lister was in stasis a radiation leak killed every other human on board the Red Dwarf and his cat's descendants evolved into a civilization of sapient humanoids in the cargo hold who worshiped him as a god. By the time Lister wakes up three million years later the cats have fought a holy war over the color of his hat and left the ship, leaving behind a few infirm or idiotic who gradually died off until there was only one left on board.
- Saturday Night Live had a series of sketches called "Bear City" in which a meteor strikes an American city, driving the human population underground and allowing the bears to rise up and fill the roles formerly filled by humans. The sketches are notable in that the humor is driven entirely through action as the bears cannot talk.
- In After The Bomb a nuclear or biological war (depending on which edition) killed off most of the human race but mutated a wide range of other animals to human-level intelligence.
- Hc Svnt Dracones features the corporate colonies on Mars mass-producing human-animal hybrids called "Vectors" to repopulate the solar system after Earth is destroyed by a nuclear war. In the successive centuries baseline humanity gradually goes extinct.
- Pugmire is set in a pseudo-medieval kingdom populated by uplifted dogs after humanity's mysterious disappearance.
- Inherit the Earth is a seemingly medieval world populated by sentient bipedal animals whose ancestors were uplifted by humanity before a plague wiped them out.
- In Riptor's ending in the original Killer Instinct, the genetic experiments Ultratech used to create Riptor end up dooming humanity and ushering in a second era of the dinosaurs.
- Paladog: After humanity is destroyed for its wickedness, animals take over to replace them.
- Splatoon takes place in a world where various sea creatures (primarily squids) have become the dominant species on Earth due to rising sea levels having led to the death of humanity thousands of years prior.
- Tokyo Jungle is set in a world in which there are no humans, the city of Tokyo is falling into disrepair without any maintenance, and a new ecosystem is forming in its ruins where multiple species of herbivores and carnivores compete for survival. The cause of this is eventually revealed to be humans from an apocalyptic future attempting to transplant themselves back to the 21st century with time travel, creating a Time Paradox which caused all present-day humans to vanish.
- In Jack, the world used to belong to humanity. That was until Jack killed them all, giving rise to the furry race.
- Unity takes place on a massive Generation Ship where the humans who originally crewed it seem to have gone extinct while the fauna evolved sapience in various ways. The main character is distantly descended from the platypus.
- Batman: The Brave and the Bold: In "The Last Bat On Earth", Batman gets trapped in the distant future where animals rule.
- Futurama: Earth undergoes this in the future in "The Late Philip J. Fry". Several times over, as a matter of fact.
- The 1939 MGM short Peace on Earth takes place After the End, where animals become intelligent and take over the world after humans kill each other down to the last man in an apocalyptic global war. A 1955 remake would change the exact cause to nuclear war.