History Main / CastSpeciation

** The sixth, seventh and tenth games do this with their Dancer-style party members. They all serve the same gameplay function, to give an ally an extra turn, and for obvious reasons only one can be on the battlefield at a time. In the sixth, you have Elphin the quiet, reserved Bard [[spoiler: who turns out to be [[KingIncognito the prince of Etruria in hiding]]]] and Lalum the cheerful flirty dancer, who are MutuallyExclusivePartyMembers. In the seventh, the similarities bewtween Nils and Ninian are justified by them being siblings, but Nils is a bard who uses MagicMusic while Ninian is a softspoken Dancer. The tenth game, Radiant Dawn, has ''three'' Herons, and this time the differences make their way into the gameplay: Raphael's chants ''always'' refresh 4 allies, [[MightyGlacier the tradeoff being that he moves slowly and can't fly]], Leanne can refresh two allies at once (either left and right or up and down), while Reyson can only refresh one ally normally but 4 while transformed.

** The whole Plastic Man/Elongated Man thing is lampshaded in ''WesternAnimation/BatmanTheBraveAndTheBold'', where the two are fighting baddies together while arguing which one of them Franchise/{{Batman}} likes more. In the end, Batman shows up and says that he doesn't really like either of them.

* ''Anime/{{Pokemon}}'' tends to use this within the main characters' groups of Pokemon, despite the preponderance of PoorPredictableRock elsewhere in the series. Occasionally, though, Ash will have two different Pokemon with similar powers and movesets; these are usually distinguished by personality.

* ''WesternAnimation/TheLandBeforeTime'' has built up a number of secondary characters over the sequels, one of the most popular being Ali, a girl who is the same species of dinosaur as Littlefoot. However, despite her popularity, she has not shown up more than twice and when a guest character was elevated to main character for the TV show, Chomper was picked instead. Admittedly he was popular in his own right, but the likelihood that the writers did not want two characters of the same species in the main group was probably a factor.

* In ''VideoGame/MegaMan9'', Mega Man lost his slide and charged shots so that he could play more like he did in the first two games. His lost abilities were instead given to Proto Man, who has the additional ability to block enemy fire while jumping. These differences were retained for the next game, which also included Bass, who can dash and has no DenialOfDiagonalAttack. Mega Man, however, does have an advantage over them by being the only character capable of using the {{Bonus Boss}}es' weapons.

** The JLA used the rule of "no two people can have the same power" to keep Hawkgirl/Hawkwoman out of the League for over a decade. Her husband eventually put his foot down about it. Of course, under that rule (as Scott Tipton once put it), the entire classic League should consist of [[FlyingBrick Superman]], [[GreenLanternRing Green Lantern]], [[GadgeteerGenius the Atom]], Wonder Woman (only for the lasso of truth) and ''possibly'' [[TheChessmaster Batman]] (the Atom's already pretty damn smart, [[BatmanGambit but not in the same way]]).

NotSoSimilar is the super trope. Compare DivergentCharacterEvolution, which happens gradually and isn't as deliberate, and SuperheroSpeciation, when it happens to superheroes and their powers. See also {{Chickification}}, a common cause of which is this trope when more than one female is in the cast.

* Downplayed in the ''Drizzt Do'Urden'' novels. Of the five main characters (six counting the mascot), four are skilled melee fighters. It's broken up by having one of them being far and away the best technical fighter; one of them being monstrously strong; another being a tough, tactical group-fighter; and [[TheChick the fourth]] usually doing ranged support. Later, one leaves, and another shows an interest in magic, while a third gets older and starts attending as much to his political duties as his military ones.

* ''Franchise/TouhouProject'' has always featured Reimu, a [[{{Miko}} shrine maiden]], who is tasked with hunting youkai and preventing them from causing trouble. Terminally selfish and lazy, Reimu sees these duties as an annoying chore, and puts little effort into her training, instead relying entirely on her [[TheGift ridiculously powerful talents]] and family tools (and she originally hadn't even bothered to learn how to use either of those). Further, she's a staunch NayTheist; as a shrine maiden, she ''should'' be establishing good relations with the gods so that they'll loan her their power, ''should'' be encouraging the people's faith in the gods so they have more power to give her... but Reimu simply can't be bothered, no matter how many youkai mock her about it. [[GrumpyBear Reimu outright believes]] [[HardWorkHardlyWorks that effort is not rewarded]]. This trope came into play when a second miko was introduced to the setting, and she was almost completely different. Sanae is dearly devoted to (and [[PalsWithJesus very friendly with]]) the two {{Physical God}}s of her shrine and glad to work for them, whether in personal service, promoting faith among the people, or hunting youkai. Sanae was born with incredible power like Reimu, but instead of random human talent, her talents are divine in origin, as one of her goddesses is also her ancestor (though Sanae was left in the dark about this until a later game); her own diligence in training her powers actually earned her the status of "deified human" from people praying to ''her'' as well as her goddesses. Finally, Sanae was born and raised in the normal, modern world outside of Gensokyo, and so brings a very different perspective to the crazy inhabitants and events of that land.

*** K-9 was added to justify the expense in building a robot dog prop for a small role in a one-shot story. This was generally awkward as his main gimmicks (SuperSenses, being LiteralMinded, carrying a weapon) were shared by Leela, and his others (maths and science knowledge, computer literacy, superior resilience, alien perspective) were shared with the Doctor. It is not uncommon, even after Leela's substitution with Romana, for K-9 to be left out of stories due to having [[AbsenteeActor nothing to do that the other characters can't do better]].

** It also [[PlayingWithATrope flip-flops]] on body designs, which are often reused to reduce the cost of introducing LoadsAndLoadsOfCharacters. Some characters in one series will share a mold, but later have different designs entirely. One example is with twins Sunstreaker and Sideswipe, whose 2008 ''Universe'' figures are the same mold, but with slightly different transformations; the chest of one is the back of the other. Meanwhile, Bumblebee and Cliffjumper were originally entirely different molds but more often than not now are simple recolors, occasionally with different heads.

* ''TabletopGame/PrometheanTheCreated'': Encouraged by the game rules. When [[ArtificialHuman prometheans]] of different [[{{Splat}} Lineages]] travel together, they balance out the [[AlchemyIsMagic humours]] that animate each other and mitigate the WalkingWasteland and HatePlague effect of their presence.

* Traditional parties of player characters in any tabletop RPG will tend to have three to five people filling specialized roles going on adventures; this tends to overlap with AnAdventurerIsYou with everyone being a different class.

* ''VideoGame/{{Touhou}}'' has always featured Reimu, a [[{{Miko}} shrine maiden]], who is tasked with hunting youkai and preventing them from causing trouble. Terminally selfish and lazy, Reimu sees these duties as an annoying chore, and puts little effort into her training, instead relying entirely on her [[TheGift ridiculously powerful talents]] and family tools (and she originally hadn't even bothered to learn how to use either of those). Further, she's a staunch NayTheist; as a shrine maiden, she ''should'' be establishing good relations with the gods so that they'll loan her their power, ''should'' be encouraging the people's faith in the gods so they have more power to give her... but Reimu simply can't be bothered, no matter how many youkai mock her about it. [[GrumpyBear Reimu outright believes]] [[HardWorkHardlyWorks that effort is not rewarded]]. This trope came into play when a second miko was introduced to the setting, and she was almost completely different. Sanae is dearly devoted to (and [[PalsWithJesus very friendly with]]) the two {{Physical God}}s of her shrine and glad to work for them, whether in personal service, promoting faith among the people, or hunting youkai. Sanae was born with incredible power like Reimu, but instead of random human talent, her talents are divine in origin, as one of her goddesses is also her ancestor (though Sanae was left in the dark about this until a later game); her own diligence in training her powers actually earned her the status of "deified human" from people praying to ''her'' as well as her goddesses. Finally, Sanae was born and raised in the normal, modern world outside of Gensokyo, and so brings a very different perspective to the crazy inhabitants and events of that land.

* Some players of the superhero MMORPG ''VideoGame/CityOfHeroes'' may avoid having more than one person on the team with the same powers or even the same class to avoid redundancy, especially as a team can only have up to eight members. On the other hand, there are cases when such redundancy may be desired if the superpowers have effects that can easily be stacked on a foe, such as with [[StatusEffects status effects]] when used against highly resistant foes.

* Some players of the superhero MMORPG ''VideoGame/CityOfHeroes'' may avoid having more than one person on the team with the same powers or even the same class to avoid redundancy, especially as a team can only have up to eight members. On the other hand, there are cases when such redundancy may be desired if the superpowers have effects that can easily be stacked on a foe, such as with [[StandardStatusEffects status effects]] when used against highly resistant foes.

** Later (and earlier) companions who had being scientific geniuses as their hat tended to be contrasted to the Doctor by terms of having a major personality quirk that modifies how they use their knowledge - Susan was fearful and childish unlike the reckless and grandpaternalistic Doctor; Vicki tended to be foolhardy and emotional; Zoe was naive and while she was more knowledgeable than the Doctor she wasn't as good as him at applying the knowledge. K-9 is a LiteralMinded RobotDog with none of the Doctor's social skills, wit or planning ability; Romana is convinced of her own superiority to everyone else and has no experience of life outside of her privilege; Adric is impulsive, [[FailureHero ineffectual]] and gullible; Nyssa is sheltered; Turlough is devious; Ace was undereducated at everything except explosive chemistry and River is a mysterious ActionGirl.

* ''{{Transformers}}'':

'''Other Black guy:''' What do you mean?\\

* In the ComicBook/FantasticFour, both Reed Richards (Mr. Fantastic) and Ben Grimm (The Thing) are highly intelligent and honored scholars and scientists, but everyone likes to focus on Ben's physical strength rather than his brain and the result is that the Thing very often comes off as BookDumb. It doesn't hurt that Ben has never been a guy who shows off that intelligence much.

* Happened a lot in ''Manga/{{Naruto}}''. Even though for the exception of ElementalPowers and inherited bloodline techniques anyone can learn anything, each character has between 1-5 special moves that no one outside of their clan or direct MasterApprenticeChain is ever seen using. The biggest example is how at the Ninja Academy, all graduates are required to learn illusory clones and shapeshifting jutsu, but only a handful of ninjas are ever shown using either jutsu even though they all should know both of them.

Does not apply to EvilMinions who sometimes come in faceless dozens, but ''does'' for, say, {{Battle Butler}}s or [[TheDragon Dragons]].

* Back during UsefulNotes/{{the Silver Age|of Comic Books}}, ComicBook/{{Superman}} and ComicBook/TheFlash were almost equally fast, with the Flash only winning a race with Superman after two draws. Modern comics have made the Flash much faster than Superman to balance out Superman having a lots of other superpowers besides just running fast. Flash [[http://i49.tinypic.com/2cg0kgl.jpg makes it clear that he wasn't even close to going all-out at the time]].

** Latter-day ''Franchise/TransformersGeneration1'' comics tend to do this a lot with faction leaders that replaced Optimus and Megatron in other continuities, retooling them to find a niche in an environment where those two are basically [[StatusQuoIsGod always going to be in the driver's seat.]] In IDW, for instance, Galvatron became a DecompositeCharacter from Megatron and had his servitude to a dark power played up to the point that he wasn't even a Decepticon for years, Thunderwing was pretty much locked into his "unstoppably mad villain" phase, Scorponok and Jhiaxus developed MadScientist inclinations, Dai Atlas and Metalhawk were unaligned (and Dai Atlas a religious leader), Overlord turned traitor and became far more violent, Fortress Maximus lost a lot of his power and became far more violent, Deathsaurus turned traitor and became far ''less'' violent, and Star Saber (most infamously) ended up as a psychotic religious zealot.

** The gameplay [[PlanetOfHats Hat]] of the [[OurElvesAreBetter Eldar]] army list, and to a lesser extent the High Elves in ''TabletopGame/{{Warhammer}}''. Each unit will have a specific situation or a specific foe they are very good at dealing with, winning relies on [[MisfitMobilizationMoment getting very varied elements of the army working together perfectly to handle any foe]].

* The gameplay [[PlanetOfHats Hat]] of the [[OurElvesAreBetter Eldar]] army list in ''[[TabletopGame/{{Warhammer 40000}} Warhammer 40k]]'', and to a lesser extent the High Elves in ''TabletopGame/{{Warhammer}}''. Each unit will have a specific situation or a specific foe they are very good at dealing with, winning relies on [[MisfitMobilizationMoment getting very varied elements of the army working together perfectly to handle any foe]].

NotSoSimilar is the super trope. Compare DivergentCharacterEvolution, which happens gradually and isn't as deliberate, and SuperheroSpeciation, when it happens to superheroes and his powers. See also {{Chickification}}, a common cause of which is this trope.

A looser adaptation of the FiveManBand. Generally speaking, it's bad form to have two major crew members on the show who essentially perform the same job (unless you have a multi-team HeroesUnlimited situation). That would lead to inevitable comparisons between the two, and probably lots of flame wars.