Sometimes in works involving animals, an animal will be portrayed by a different species, subspecies, or breed than what it is supposed by in in-universe. A good reason for this may be that the intended species may not be available for acting, so the filmmakers instead use a similar species. This may be because the species is either very rare, extinct, or imaginary. (For example, a unicorn may be portrayed by a horse wearing a fake horn.) Another reason may be that the species meant to be portrayed is too dangerous so the filmmakers instead use a similar species which is easier to handle. Sometimes makeup or prosthetics may be applied to the animal to make it look more like the species meant to be portrayed.
This trope is frequently used for extinct and fictional species, especially if said species is similar enough to a real living species that it can be portrayed by such. (In this case, the trope would obviously be justified since, for obvious reasons, the producers could never find an actual living individual of the species meant to be portrayed.) Otherwise, they would most likely be CGI.
Related tropes include Adaptational Species Change and Slurpasaur. The former contrasts with this trope in that it is about a species formerly portrayed being changed in a later adaptation of said work. The latter mainly involves using lizards and similar ordinary modern reptiles to portray dinosaurs.
This trope would mostly be limited to live-action television and films as opposed to animated (unless you count in-universe examples), since cartoon animals are not actually "played" by real animals.
Could be considered a sister trope to Informed Species (where an animal looks nothing or little like the species it is supposed to be). Incorrect Animal Noise may be in effect if a recording of an animal sound is used for a different species.
- A Kleenex tissue commercial has a boy taking in a raggedy stray dog. The dog is a Border Terrier, however it's meant to be a mixed breed in the narrative.
- This is used as a joke in a Kirby 64: The Crystal Shards commercial. A woman refers to Labrador puppy as a Lab/Husky mix to set up a joke about Kirby also being a mix.
- The elephants in the Tarzan films are portrayed by Asian elephants, even though the films take place in Africa. Granted, Asian elephants are much easier to train than their African cousins. In the first film, cardboard ears were attached to them to make them look more like African elephants.
- Wolves in a lot of movies are played by wolf-like domestic dog breeds, such as German Shepherds or Huskies. For example, the wolf in Old Yeller was played by a German shepherd made to look like a wolf.
- In Sheena, Sheena rides a "zebra" that is played by a horse with stripes painted on it.
- In a few shots, Gorillas in the Mist used trained chimpanzees wearing gorilla makeup (in most shots they were either actual gorillas filmed in the wild or Rick Baker in a gorilla suit).
- In the 1994 remake of ''The Jungle Book'' Baloo is portrayed by an American black bear rather than a sloth bear. This may be because sloth bears are an endangered species and American black bears are more common in captivity.
- The Ghost and the Darkness: Based on the account of John Henry Patterson, the film follows him as he spends the better part of a year hunting down the infamous Tsavo Man-Eaters, a pair of male lions who were responsible for the deaths of at least twenty to thirty railroad workers, as they endeavored to construct the Kenya-Uganda Railway. While the films heavily tones down a number of the more seemingly fantastical aspects of the real story, as it was deemed the audience wouldn't believe any of it, one of the more bizarre changes was with the lions themselves. Despite the lions being portrayed by, well, real lions, the pair of males the film used have manes. Among Tsavo's lion population, male lions, including the aforementioned Man-Eaters, are unique for being mane-less.
- Mutts and mixed-breed dogs are usually portrayed by purebreds in film, as it's easier to find multiple similar-looking purebreds. One example is the title character in the film adaptation of Because of Winn Dixie, who's stated to be a mutt but is played by a Berger de Picard.
- In the Marmaduke film the "mutts" are played by a Great Dane, an Australian Shepherd, a Chinese Crested, and a Dachshund.
- In Lady and the Tramp (2019), the mutt Tramp is played by a Miniature Schnauzer. Peg, another mutt, is played by a Pekingese.
- The Killer Shrews: The giant shrews were played by dogs in shrew costumes.
- The Giant Gila Monster: The titular mutant lizard is actually played by a Mexican Beaded Lizard, not a Gila Monster (which looks similar but is more poisonous).
- As covered by Slurpasaur, many dinosaurs used in old black and white films have been portrayed by modern reptiles such as alligators and iguanas. (Though some films have used stop-motion animation, people in rubber suits, and/or animatronic puppets.) Nowadays, most dinosaurs in live-action films and television, such as the Jurassic Park films are CGI. The animals alive today that most closely resemble dinosaurs are probably modern reptiles and birds, and few if any of them would actually pass convincingly as dinosaurs no matter how much they were made up and what special effects were used. (For example, it wouldn't be very convincing to portray a Komodo dragon as a Tyrannosaurus rex.)
- A prehistoric animal example: Quest for Fire features some saber-toothed cats which are played by trained lionesses with prosthetic saber-teeth.
- In Cannonball Run 2, one team finds themselves doing the race with a simian. All of the dialogue refers to said simian as a "chimp", but it's actually an orangutan (and is identified as such in the credits).
- The seal in the eponymous film Andre was played by a sea lion. This is because sea lions are easier to train to do tricks, and are more often kept in captivity.
- Ringling Bros. and Barnum and Bailey's Legends show included horses dressed as unicorns and a Pegasus, and an Asian elephant dressed as a woolly mammoth.
- Real Life Example: Some real life places allow guests to interact with "live unicorns", which are usually actually horses wearing prosthetic horns. In former decades, "real" unicorns were also created by transplanting the unfused horn buds of baby goats to the middle of the forehead, where they fused and merged to form a single straight horn. Given that unicorns are imaginary, these are pretty much the closest you can get to seeing one in real life.
- A similar concept involving humans is Weeki Watchee Springs, famous for their mermaid shows (where women swim around wearing fish-tails).
- In Red Dead Redemption II, a side quest involves a traveling circus that has lost its animals. You discover, upon finding them, that the "zebra" is actually a donkey with stripes painted on and that the "tiger" is similarly an artificially-colored cougar, and the "lion" that got eaten by the "tiger" was in fact a dog. In the last mission, you must find the other lion, and Arthur is fully expecting it to be another dog. Nope: that one is a real lion.
- Parodied in The Simpsons episode "Radioactive Man", when a group of Springfield children see a painter on a movie set painting black spots on a horse to make it look like a cow.
Martin: Uh, Sir, why don't you just use real cows?
Painter: Cows don't look like cows on film. You gotta use horses.
Ralph: What do you do if you want something that looks like a horse?
Painter: Ehh, usually we just tape a bunch of cats together.