->'''Ripred:''' You thought I'd be its daddy?\\
'''Gregor:''' Or, at least its teacher. One of the other rats could be its parent. Just for, you know, eighteen years, or whatever.\\
'''Ripred:''' Ah, here's something you obviously don't know about rats. That ball of fluff over there will be full grown by the time you've seen another winter.
-->-- ''[[Literature/TheUnderlandChronicles Gregor and the Prophecy of Bane]]''

In animation and comics, animal characters develop and age like humans. In reality, they tend to have much different lifespans, ranging from mere weeks to centuries longer than any human could hope to live. In addition, they usually develop quite differently and sometimes have life stages that are completely alien to humans. For example, frogs and toads have tadpole, froglet, and adult stages, butterflies and moths have larval (caterpillar), pupal, and adult stages. Crickets and grasshoppers have nymph and adult life stages, which are less drastic.

This trope takes on four different forms, human-like lifespan and longevity, human-like aging process, human-like developmental process, and human-like baby animal body proportions.

* '''Human-like Lifespan/Longevity:''' This is when an animal character has the same longevity as a human, that is, live as long as a human. Depending on the species this is either accomplished by shortening or lengthening their life span, though the lengthening of the short-lifespanned animals form is far more common. A way to avert this is to use the species' normal life span, and give a multiplier to calculate how old the animal would be if it was a human.
* '''Human-like Aging Process:''' This is when an animal character shows their age in the way that a human does. Examples of this include gray hair or fur even on a [[NonMammalianHair non-mammal character]], wrinkles, liver spots, bushy eyebrows, [[AnimalFacialHair mustaches, and/or beards]], balding head (often in the form of FurryBaldness), and sagging NonMammalMammaries.
* '''Human-like Development Process:''' This is when an animal character develops in the way or at the pace that a human does.
* '''Human-like Baby Animal Body Proportions:''' This is when a baby animal is inaccurately given body proportions like those of human babies. For example, real-life calves, fawns, lambs, and foals have long legs, so that they can stand shortly after birth and reach to suckle. Some examples are animal equivalents of the ThreeMonthOldNewborn trope.
* '''Precocial Altricial Baby Animals:''' This is when a baby animal of an altricial species is inaccurately portrayed as less altricial or more precocial than in real life. One variant is an animal that is born furless or hatches featherless in real life is depicted as being born fully furred or being fully feathered when it hatches. Newly-hatched songbirds, parrots, and pelicans are featherless and helpless in real life, but tend to be portrayed as fluffy, yellow, and precocial as ducklings and chicken chicks in fiction. Some examples are animal equivalents of the ThreeMonthOldNewborn.

Averting or lampshading this trope is sometimes done as a FurryReminder.

----
!!Human-like Lifespan/Longevity Subversions, Lampshades, and Exceptions:

[[foldercontrol]]

[[folder: Anime And Manga ]]

* Akamaru from ''Manga/{{Naruto}}'' is two years old at the start but is still only a small puppy. Within not even three years, he hit a huge growth spurt. As a puppy he rode on Kiba's head, but as an adult Kiba could ride him like a horse. In the [[DistantFinale final chapter]] he's very, very old looking but alive over ten years later. Large dog breeds tend to have short lifespans. At six Akamaru is a sprightly adult but for even small dogs that's nearing the end of middle aged. In Akamaru's case it can be justified in that he's a fictional breed of ninja dog.

[[/folder]]

[[folder: Comic Strips ]]

* Originally averted by ''ComicStrip/{{Garfield}}'', who mentions on his second birthday that he's the human equivalent of fourteen, and complains about aging ever since he turned four. Later played straight, as he's still relatively healthy and active over 40, though the average lifespan of a housecat is 12-14 years, and the oldest cat ever recorded lived for 38 years.

[[/folder]]

[[folder: Fan Works ]]

* The ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' fanfic ''FanFic/AMightyDemonSlayerGroomsSomePonies'' zig-zags this. In the ancient era, Ponyland's ponies age like horses (a pony remarks that an eleven-year-old human is "two in pony years"). Over the next several thousand years (by the ''Friendship is Magic'' era) they become much more humanlike, including having a human lifespan and aging at a human pace.
* Inverted in ''Fanfic/ClaroDeLuna'', Octavia (a pony) died of old age at twenty-six. This accentuates the MayflyDecemberRomance between her and the millenia old Luna. In canon, ponies are shown to age comparably to humans.
* Implied in ''Fanfic/LettingGoOfHate''. Kiara, an almost-fully-grown lion, mentions having been a "preteen" once.

[[/folder]]

[[folder: Franchise ]]

* In every [[Franchise/TeenageMutantNinjaTurtles TMNT]] incarnation, the Turtles are [[UpliftedAnimal Uplifted Animals]] that are aging like humans (such as how they are fifteen and act like American teenagers). Master Splinter depends on the writer: if he's a mutated human, then he's still aging like a human despite looking like a rat. However, if he's an UpliftedAnimal like the Turtles, then he's a rat who's natural lifespan has been extremely extended. [[note]] While Splinter's canon age is rarely (if ever) stated, most rats only live to be a year or two. [[/note]]

[[/folder]]

[[folder: Film ]]

* In the first ''WesternAnimation/Madagascar1'' when Marty the zebra turns 10, it's hinted that he is middle aged at that age. Zebras can live to be 40 years old in captivity.
* It's justified in the case of ''WesternAnimation/TheSecretOfNIMH'', where the rats and mice who were experimented on at NIMH were given long lifespans. It's mentioned that Johnathan Brisby would have far outlived his wife, a simple field mouse, had he not been killed by a cat first.
* In ''WesternAnimation/FantasticMrFox'', the characters' ages are often given in fox years. Apparently six fox years is about as long as a normal year; Ash is two years old in non-fox years, but about twelve in fox years (and is about as developed physically and mentally as a twelve-year-old human child). Mr. Fox gives his age as seven non-fox years, which makes him about as old as a forty-two year old human.
* In ''Animation/WillyTheSparrow'', Willy (a human [[ForcedTransformation transformed into a sparrow]]) and Cipur are exactly the same age. Willy is in his early teens, Cipur is a very old bird.
* In ''WesternAnimation/BeeMovie'', bees have go through three days of grade school, high school, and college each before entering the working world, matching with the 1-2 months honeybees can live up to in real life.

[[/folder]]

[[folder: Literature ]]

* Mentioned but not elaborated upon in ''The Beginning'', the last book of the ''Literature/{{Animorphs}}'' series. Tobias, a human trapped in morph as a red-tailed hawk, briefly mentions that he's old for a red-tail, but he has absolutely no idea how much time he has left.
* Justified in ''Literature/HarryPotterAndThePrisonerOfAzkaban'' in regards to Scabbers, Ron's pet rat that had been alive for at least 12 years and had belonged to Ron's older brother before him. Ron is told by a magical pet shop owner that a plain country rat such as Scabbers generally doesn't live more than a few years, but of course it's revealed that [[spoiler:Scabbers is really Peter Pettigrew, a traitor and presumed dead wizard in disguise.]]
* Companions in ''Literature/HeraldsOfValdemar'' resemble [[CoolHorse beautiful]], [[IntellectualAnimal intelligent white horses]] but they live as long as the [[BondCreatures humans they've bonded to]] do - and usually choose humans in their early teens. After being born they take about ten years to grow up and make their choice. Of course, they aren't horses and tend to take offense when ''called'' horses - they're [[OurAngelsAreDifferent essentially angels]], the reincarnations of virtuous humans helping to guide and support their Chosen. A few Companions straight up live for centuries or unless they're killed, but those are essentially archangels BornAsAnAdult anyway.
* The woodland creatures of ''Literature/{{Redwall}}'' track time's progression by seasons, not years, presumably because of their respective species' shorter-than-human lifespans.

[[/folder]]

[[folder: Puppet Shows ]]

* On ''Series/BearInTheBigBlueHouse'', Grandma Flutter has her 100th birthday in "Grandma Flutter's 100th Birthday." A typical lifespan for a domestic pet mouse is about one to two years, the Guinness World Record for the oldest pet mouse is 7 years and 7 months.

[[/folder]]

[[folder: Video Games ]]

* ''VideoGame/BugFables'' justifies this trope as part of the AnthropomorphicTransformation brought upon by the "Great Awakening". Notably, the lifespans seem to be increased proportionally; termites still live longer than ants, and the queens are implied to live for even longer than that, with the Ant Kingdom innkeepers having gone through several generations in the time it took for a single change of Ant Queen.
* While canon ''Franchise/SonicTheHedgehog'' material treats the characters as if they age like humans, the American ''Script/SonicTheHedgehogBible'' featured a version of this where Sonic didn't age like an actual hedgehog, but also didn't age like a human either. It took only a year for him to turn into the equivalent of a teenager.
* Arizona from ''VideoGame/ThemsFightinHerds'' is a one year old PartiallyCivilizedAnimal calf. Other characters age similar to their real counterparts. Unicorns and longma age slower than "normal" animals.

[[/folder]]

[[folder: Visual Novels ]]

* The birds of ''VisualNovel/HatofulBoyfriend'' are all [[UpliftedAnimal uplifted]], large and sentient. They grow up somewhat more slowly than normal birds, but faster than humans. Yuuya mentions that doves hit sexual maturity before they're a year old. They also live longer than normal birds but still have shorter lives than humans, though it's never said just how long. Normal pigeons in good conditions can often reach fifteen years of age, but there are reports of individuals reaching forty.
* Inverted in ''VisualNovel/{{Nekopara}}'' as a case of [[InvertedTrope Animallike Human Aging]] -- all catgirls grow and age like their real life counterpart. The most absurd example goes to Coconut; being a Maine Coon, she has the body of an adult woman despite being ''[[YoungerThanTheyLook one year old]]''.

[[/folder]]

[[folder: Webcomics ]]

* ''Webcomic/InOurShadow'' takes place in a world where AnimalIsTheNewMan and many species have evolved a humanlike body structure, but their lifespans still remain closer to what they were originally. Few animals live longer than a decade, and rats are said to have a lifespan of around seven years. Using a device known as the Neural Flare can extend one's lifespan as a side-effect, and this is how [[BigBad Emperor Schorl]] has managed to live several times longer than most rats.
-->'''[[https://tapas.io/episode/244511 Schorl]]:''' ''(internally)'' Perhaps this is what it means to live so astronomically long. Forty-six years. How did the humans do it?
* ''Webcomic/{{Tamberlane}}'': Aging isn't addressed in the main comic so far (2022), but mentioned at cast pages and Patreon extras. Humanoid animals mature 20-30% faster, more so at younger ages. Belfry's late teens equals human mid-twenties. Tamberlane's 3-4 human years equals animal 2-3.

[[/folder]]

[[folder: Western Animation ]]

* The lifespan part of this trope is averted with Brian Griffin the dog from ''WesternAnimation/FamilyGuy'' as occasional references are made to his age (seven) and longevity. Also, Peter also addressed the fact that Brian will only live a fraction of the time Peter will.
* One episode of ''WesternAnimation/PinkyAndTheBrain'' hinted at the lifespan of real mice, which is 2-4 years. Brain says that at 2 years old, he's lived half his life.
* This isn't mentioned, but it's strongly implied in ''WesternAnimation/ChipAndDaleRescueRangers''. In the pilot, when Gadget is added to the group, it's mostly because she is the daughter of a friend of one of the protagonists, and she is the only one who can fly his plane now that he is dead. It is mentioned that said friend and protagonist fought together in "The Great War", which seems to be an expy war for UsefulNotes/WorldWarII. For any of this part of the pilot to work, either:
** a) Gadget was born about a decade or so after the real actual [=WWII=], making her actually anywhere from 20-30 something at the time of the pilot
** b) The Great War isn't an expy for [=WWII=], but a more recent conflict such as Vietnam, and Gadget is actually 12, and demonstrating a "puberty = adulthood" trope
** c) Gadget and every other animal is aging just like they should, The Great War happened in the past 3 or 4 years, is not an expy for any human war, and is an expy for a covert black ops action instead
** d) It's not the late 80's in the show
** As all the visual evidence, parody, and inferences point to a) (right down to the plane they fly), and in the show, it's clearly the late 80's, this trope has to be in play.
** Also of note is that Monterey Jack references surviving things that supposedly happened decades ago in his long rants about the past (braving the "Great Blizzard of '38" for example). How truthful they are varies, however.
* ''WesternAnimation/PoundPuppies2010'' lampshades this trope in one episode.
* Surprisingly averted in ''WesternAnimation/DoraTheExplorer''. A Christmas episode shows that Swiper, Boots, and several of the animals are the exact same age. Boots is a child, Swiper is an adult, and the others are varying degrees of [[VagueAge vague]]. When they go into the future less than six years Swiper, who is a fox, is a senior while Boots the Monkey isn't even a teenager yet.
* ''Franchise/ScoobyDoo'': Scooby is a seven year old Great Dane. Danes have a typical lifespan of under ten, and even to a smaller breed seven would be old, but Scooby isn't presented as anything but a young adult.
* In ''WesternAnimation/AllHailKingJulien'', the GrumpyOldMan lemur is implied to be in his 20s, which would be an appropriate age for an old lemur, who have been known to live to their 30s. Meanwhile, Mort implies that he could be as old as ''50'', which is remarked upon by Julien to be an excessively high age for a lemur.
* One episode of WesternAnimation/PuppyDogPals Bingo and Rolly celebrate their first birthday, they should be fully grown but they still have child voices and are still referred to as puppies.

----
!!Human-like Aging Process Examples:

[[foldercontrol]]

[[folder: Anime And Manga ]]

* ''Manga/NagasareteAirantou'': The animals of the island, besides looking strange to outsiders, age at the same pace as humans. And also has the same average life span as well.
* In ''Manga/OnePiece'', the Fishmen (a FishPeople, not a HalfHumanHybrid) age not unlike humans. Evidenced in Hody Jones and his New Fishman Pirates, who, after a steroid-induced RapidAging, are shown with wrinkles, saggy eyesockets, gray beards and teeth loss.
* In ''Manga/CellsAtWork'', the cells age like the body they protect rather than the short lifespans a real life cell has. In spinoffs, they even match the host body's age: [[Manga/CellsAtWorkBaby babies]] get child-aged cells, for example. The short turnaround is acknowledged in-universe, though it's represented as the cell merely getting a new uniform to wear and continuing as normal.

[[/folder]]

[[folder: Film ]]

* We could know that Master Shifu in ''Franchise/KungFuPanda'' is old by his white mustache, bushy eyebrows and grayish fur (and not to mention [[MiniatureSeniorCitizens being really small]]).
* Rufus the cat from ''WesternAnimation/TheRescuers'' has a grey moustache that indicates his old age.
* Jock the Scottish Terrier from ''WesternAnimation/LadyAndTheTramp'' has a grey moustache and bushy grey eyebrows.
* While he certainly has a far longer than human lifespan, some of the clues to ''Franchise/StarWars''' Yoda's advanced age include wisps of gray hair and the fact that he is almost always seen either walking with a cane or in a scifi version of a wheelchair.
* The animals in ''Animation/LeafieAHenIntoTheWild'' age realistically however an older duck is shown with markings resembling a grey beard and bushy eyebrows.

[[/folder]]

[[folder: Tabletop Games ]]

* Inverted with ''TabletopGame/Warhammer40000'''s Space Wolves, who undergo Animal-like Superhuman Aging: As they grow older, Space Wolves gain wolf-like characteristics thanks to a mutation of their geneseed: their hair grows gray (from its original black, blond or red), their canine teeth grow more prominent, and their eyes turn gold. Some even go too far, becoming animalistic Wulfen.

[[/folder]]

[[folder: Western Animation ]]

* In "The Old Gray Hare", after a FlashForward to the year 2000, a 70-or-so-year-old WesternAnimation/BugsBunny is shown with white chin whiskers.
* The ''WesternAnimation/TomAndJerry'' cartoon "The Missing Mouse" has Jerry Mouse pose as an escaped lab mouse filled with a volatile explosive. Jerry's ruse dissolves, however, and Jerry gets booted out of the house. Tom soon captures another mouse, thinking Jerry is repeating the trick. When Jerry shows himself elsewhere, though, Tom realizes that he's abusing the explosive mouse. This realization ages Tom dramatically: white eyebrows, white ear-hairs, baggy skin, collapsed posture. He looks like a centenarian.
* The grandmother in ''Literature/MaxAndRuby'' is grey furred instead of white furred like her grandchildren.

----
!!Human-like Development Process Subversions, Lampshades, and Exceptions:

[[/folder]]

[[folder: Film ]]

* Many coming of age Disney movies that feature {{Nearly Normal Animal}}s, like ''WesternAnimation/{{Bambi}}'', ''Franchise/TheLionKing'', ''WesternAnimation/LadyAndTheTramp'', and ''WesternAnimation/TheFoxAndTheHound'' avert this by showing the animals develop and age like their real counterparts.

[[/folder]]

[[folder: Literature ]]

* In the ''{{Literature/Redwall}}'' series most animals seem to use "seasons" as a substitute for years, Tagg for example is stated to be an adult at 16 seasons. They seem to equate one season to one year, and that's still far too slow. In the example that's given of Tagg, to be realistic he would have had to have been an adult by around 13 months, or just over four seasons. Also, the mice ought to be fully grown in well under one season.

[[/folder]]

[[folder: Western Animation ]]

* While other material for ''Franchise/TheLionKing'' averts this, ''WesternAnimation/TheLionGuard'' does not. Kion and Kiara are not litter-mates yet are close in age. In real life lions have larger gaps between litters and Kiara should look older.
* In ''WesternAnimation/DuckTales2017'' ducks are actually born from eggs which has a surprising amount of plot relevance, [[spoiler:because it means Della has never seen her sons alive in person. This drama obviously wouldn't be possible if they were born alive like humans are.]]

----
!!Examples of Human-like Baby Animal Body Proportions:

[[/folder]]

[[folder: Film ]]

* Zig-zagged with the fawns in ''WesternAnimation/{{Bambi}}'' as they have long, ungainly legs like real fawns, but round heads and high foreheads like human babies.
* The calves and lambs in the ''Mickey and the Beanstalk'' of ''WesternAnimation/FunAndFancyFree '' have long, ungainly legs like real calves and lambs. In fact, many other classic Disney works that show calves, lambs, and fawns show them with the correct leg proportions.
* Newborn lions in ''Franchise/TheLionKing'' are basically the animal equivalent of the ThreeMonthOldNewborn trope. They're large and already have their eyes open.

[[/folder]]

[[folder: Video Games ]]

* ''VideoGame/{{Minecraft}}'':
** Calves (baby cows) with large heads and stubby legs. However, the foals (baby horses) have long legs, like real foals.
* ''VideoGame/StoryOfSeasons'' usually plays this straight, as the babies are typically stubby mini versions of their mother. ''VideoGame/HarvestMoonAWonderfulLife'' averts it by having realistically proportioned animals.

[[/folder]]

[[folder: Western Animation ]]

* ''WesternAnimation/{{Barnyard}}'' and ''WesternAnimation/BackAtTheBarnyard'' both feature calves and lambs with large heads and stubby legs.

----
!!Examples of Precocial Altricial Baby Animals:

[[/folder]]

[[folder: Film ]]

* In ''WesternAnimation/{{Ratatouille}}'', all the baby rats that are seen evacuating the colony's old home are fully furred and open-eyed, with not a pinkie to be seen.
* ''WesternAnimation/ABugsLife'': The baby songbirds [[spoiler: at the end that devour Hopper]] are shown to be cute and fluffy, like baby chickens. In truth, the newly-hatched young of many songbirds are in fact blind, featherless and rather hideous-looking, at least for the first few weeks.

[[/folder]]

[[folder: Video Games ]]

* ''VideoGame/{{Minecraft}}'':
** Kittens, both ocelot and cat [[note]]Cats ingame are the domestic forms of ocelots (or were, prior to the 1.14 update), whereas real life cats are domestic Near Eastern wildcats (Felis silvestris lybica)[[/note]], are born with their eyes open and with their genetically predetermined eye color (green for the black tuxedo and ginger tabby cats and blue for the seal point Siamese cats) already showing, making them literal ThreeMonthOldNewborn kittens. Real cats/wildcats open their eyes at seven days and their adult eye color appears at as early as six weeks.

----
!!Examples of Two, Three, Four, or All Forms:

[[/folder]]

[[folder: Film ]]

* ''WesternAnimation/TheWild'': Ryan is stated to be 11 years old in the movie. Even though he's still a cub, realistically a lion his age would be considered an adult or middle-aged.

[[/folder]]

[[folder: Literature ]]

* Averted in ''Literature/WarriorCats''. Aside from a few inaccuracies, they age and develop just like real cats do. The exceptions to the lifespan rule are the clan leaders, who have nine lives. They measure the ages of kittens in "moons", with the kittens being promoted from "kits" to "apprentices" at six moons old (equivalent to a pre-teen human child).

[[/folder]]

[[folder: Roleplay ]]

* Zigzagged in ''RolePlay/WeAreAllPokemonTrainers'', while most species of Pokémon can live at least as long as humans, and others live shorter or even longer lives (With ghosts and inorganic mons being immune to death by old age), Pokémon generally physically and mentally mature at an accelerated rate compared to humans.

[[/folder]]

[[folder: Western Animation ]]

* ZigZagged in ''WesternAnimation/MyLittlePonyFriendshipIsMagic'':
** Ponies seem to live as long as humans. On the other hand, baby ponies seem to develop very quickly, like real horses. Also, though it's debated to what extent it was intended to imply this, the very elderly Granny Smith was present for the founding of Ponyville, and that was later established to have happened quite some time ago. If taken at face value, Granny's been in the triple digits longer than most of the cast has been alive, with other generations having come and gone, suggesting that rarely, some ponies can live a great deal longer than is normally possible. The comic character Professor Inkwell is a similar case: looks very old now; looked younger when some adult ponies were children... and looked just as young for events that should be well before her time even then, but it's unclear if it's WritersCannotDoMath at work.
** The episode "The Cutie Mark Chronicles" reveals, in a flashback, that Fluttershy as a filly resembled a real filly with long legs, compared to the others which are just smaller versions of their adult forms. Presumably, this was to illustrate what a late bloomer she was. Alternatively, it's to illustrate that she's older because she looks taller than the others.
* Many of the forms are played straight with Rex from ''WesternAnimation/{{Gawayn}}''.

----

!!Discussions:

[[/folder]]

[[folder: New Media ]]

* The author's note of the Animaton World Network article, [[http://www.awn.com/articles/drtoon/dr-toon-showing-their-age Dr. Toon: Showing Their Age]] talks about what WesternAnimation/WallyGator's physical age would probably be.
-->Author's note: As to the probable age of Wally Gator, I offer the following formulations: [[note]]In terms of developmental progression, anyone above the age of 12 is said to be in Jean Piaget's Formal Operational stage, defined by the ability to think in the abstract. Wally has a defined idea of the difference between freedom and captivity. Erik Erickson would likely place Wally in the Intimacy vs. Isolation stage; Wally yearns for the intimacy of societal contact, not the isolation of the zoo. This stage is typified by young adulthood. A biological examination reveals the average lifespan of the male American alligator to be roughly 40 years in the wild. The average lifespan of the human male is 76 years. Thus, one alligator year is equal to about two human years. It is probable that Wally Gator at least 12 in alligator years, since he evidences abstract thought. This makes Wally at least 24 in human years. This age demographic would fit neatly into the Ericksonian stage of Intimacy vs. Isolation. In watching Wally Gator, who does appear to be in his younger years, we can assume that Wally Gator's chronological age is 12 at the least and 14 at the most. I hope you know that I stayed up all night working on this, since I never seem to get much sleep anyway.[[/note]]
----