Swimming isn't easy to animate in a video game. First of all there's the complexity of underwater effects. Then there's the freedom of movement in three dimensions, which is neat for the player, but a real pain to achieve in third-person games in terms of achieving an intuitive interface and a fluid camera. Then there's the problem of water meeting land — it's easy enough to have your character jump or fall into water, but to get them out again you'd need ladders, shores, so forth, so you're going to have to do your art direction with that in mind. And to be even slightly realistic you'll need to think about the character's oxygen supplies. Basically, having your character be able to swim means adding an entirely new form of gameplay that's usually boring, annoying and nowhere near worth it.
The most common solution is to have no water, at least nothing more than ankle deep. But since our world is full of the stuff another very popular solution is to declare that the lead character of this game, no matter how athletic, trained and/or super-powered they may be, is just that: Lead. They cannot swim at all, not even enough to thrash around a bit. They just sink like a stone or are helplessly swept away by strong currents and are gone forever. It gives a new meaning to Hazardous Water.
Some games have decided that it is worth it, and thus attempt more realistic solutions, with varying degrees of effectiveness. Quake, an early example, would deal damage to your health if you were underwater too long. However, armor protects against this damage — meaning you can stay underwater longer if you wear full body armor. Earlier still, the Ultima Underworld or The Elder Scrolls: Arena games didn't let you go underwater—swimming was essentially the same as walking except you bobbed up and down more and couldn't use a weapon, but after some amount of time your health would start taking a battering. The Tomb Raider games and the later The Elder Scrolls have Oxygen Meters that would deplete as you swam, with running out causing lots of damage to be dealt, resulting in swift death. Other techniques have also been used to increase realism and decrease the prevalence of this trope.
Another solution is to put the main character in an environment suit, like in Halo. Which doesn't explain why the apparently perfectly ordinary land vehicles don't suffer from hydrolock when submerged. Even then, some bodies of water may still act as Bottomless Pits.
Interviews with developers note that this trope exists to avoid a few other tropes, such as Insurmountable Waist-Height Fence or Border Patrol as water is a more "logical" method than a fence or invisible wall. Additionally it removes the need for extra assets taking up inventory slots that don't get used a lot. Sometimes, an item that allows one to swim will be presented - usually to keep the player from going places they shouldn't be able to yet.
Important: If your drowning skills come with an Oxygen Meter, they're not Super.
Contrast Super Not-Drowning Skills for characters who can stay underwater indefinitely with no apparent means of breathing, as well as Olympic Swimmer for those with more realistic submersion behavior but unrealistic swimming abilities.
- Episode 2 of Angel Beats! saw a Dwindling Party scenario deep underground (it's the afterlife, so Death Is Cheap and Played for Laughs). Right before the commercial break, the group is down to four members. Fujimaki predicts newcomer Otonashi will be the next to die. Right after the break, the group find themselves in the aftermath of a water trap. Guess who's floating like a dead goldfish?
- Assassination Classroom: This is one of Koro-sensei's greatest weakness. His body will bloat and become immovable when he's underwater due to being highly absorbent. Ironic, for a creature that looks like and often compared to an octopus.
- Azumanga Daioh's Osaka is able to swim just fine, she just can't float.
- And for that matter, so can Gaossmon from Digimon, according to supplementary materials. Finding one passed out in a puddle is apparently a common sight.
- Nobita Nobi from Doraemon can drown in puddles. He is hopeless at swimming despite being taught once how to swim and was once provided with an imagination pill to make him think that he was in a swimming pool.
- In episode 3 of Free! the newest member of the team, Ryugazaki Rei, reveals that he can't actually swim. He chooses to reveal this by belly-flopping into the pool and nearly drowning so Nagisa and Haruka have to rescue him. Rei eventually learns how to swim.
- Ledo does this in Gargantia on the Verdurous Planet when he first tries out one of the Earthling's yunboroid. While his own mecha can indeed maneuver underwater fairly well, the primitive controls on the Earth yunboroid isn't intuitive to him, so he flails around a bit before sinking. Justified however, because he was born and grew up in space, so there was no need for him to learn swimming skills.
- Hekikai No Aion: Seine can't swim. Even in a kid's pool with water-wings, she sinks like a rock. She also fights the people of the sea. The irony.
- Gentoku Ryuubi from Ikki Tousen. Usually played for laughs since she's a klutz as well. It's played more seriously in when she jumps into a huge pond to rescue a drowning Koumei while fully knowing the risks. They survive, but barely.
- One Piece:
- Anyone who has eaten a Devil Fruit gains a special power, at the cost of losing the ability to swim in the ocean. In fact, having at least half of their body submerged will not only prevent them from using any abilities granted by the fruit, but will drain all strength out of them to the point of near paralyzation, causing them to sink. This is inconvenient, since most of the characters are sea-faring pirates on a planet with even less landmass than the Earth. Note that only actual submersion and seawater counts; rain is harmless and DF users can still take showers according to Word of God. A few people (mostly winners of the Superpower Lottery) have Devil Fruit powers that at least partially negate this weakness. Aokiji for example, An Ice Person, freezes the water just by coming into contact with it, giving him a massive advantage over other Devil Fruit users; also, Protagonist Monkey D. Luffy still has an elastic body regardless of whether he's in water or not, so he can have somebody else stretch his head outside of the water (he'll still be paralyzed, but he will then be able to breathe, at least).
- Even before he ate the Devil Fruit, Luffy couldn't swim and was given the nickname "Anchor" by Shanks' crew, so he'd have Super Drowning Skills regardless.
- The worst part: at times, Tony Tony Chopper would jump in after Luffy if the latter ended up in trouble in the sea, forgetting he can't swim either. Upon which Brook would jump in after Chopper, ALSO forgetting he can't swim. Then they get saved by Franky who swims perfectly despite being mostly made out of metal.
- A good example of the toll this can take is with Buggy. He "accidentally" swallowed a Devil Fruit he was planning to steal and sell when he was startled by Shanks. He still holds a grudge to this day. Why? Because he was an excellent swimmer before he ate it and planned to swim to a very large amount of treasure hidden in the sea.
- Fishmen, Mermain and Mermaids who ate Devil Fruits won't be able to move when they are in the sea, but they won't drown. There are special bubbles that allow you to move in water as long you are inside the bubbles. Known Fishmen with Devil Fruit abilities are Van der Decken IX. and Captain Jack, one of Kaido's top 3 subordinates.
- Masuzu in Oreshura nearly drowns in episode 5 after climbing slowly into the swimming pool upon hearing rumors from other girls that she was deliberately not swimming to draw attention to herself from the guys. Eita is forced to perform CPR on her when he sees the swim teacher giving CPR to another student at the time, causing the other students to Squee! at the "kiss" he's giving her.
- In Pokémon:
- Misty's Psyduck doesn't know how to swim despite being a Water type. A few attempts have been made, but it ends in failure every time. He seems happier with an inner tube, though. You'd think that maybe not it's so bad if you consider that a Psyduck, despite the name, is probably more of a platypus than a duck (no wings, doesn't learn a single "bird-related" move, can interbreed with mammals and assorted aquatic creatures rather than birds.) The problem is that platypi naturally float, anyway, to the point of requiring constant swimming to stay submerged. Otherwise, they just bob right back up to the surface. This means Misty's Psyduck has even fewer excuses for its incompetence in the water than before.
- The Magikarp James bought from the salesman during the S.S. Anne mini-arc couldn't swim, either. It's a fish. That can't swim. (We saw Magikarp swimming in the first episode, for bonus points.)
- A debatable example would be Ash Ketchum himself. Ash has been known to find himself in a watery situation more than once. Despite having impassive lung capacity for a ten-year-old, he tends to be extremely reckless when swimming, often diving deeper than he should, or coming into some other form of trouble. A good amount of the time, he needs to be rescued after losing consciousness.
- Ranma ½:
- Akane Tendō panics and cannot swim even when her life really does depend on it. Even wearing a flotation device, she manages to sink like a rock. Even when the water is only knee-deep. Until she was explicitly told otherwise near the end of the manga, she honestly believed you were supposed to breathe while underwater. Discovering that you have to hold your breath was nothing short of an epiphany for her.
- Played with in a very nasty way when, during the final arc of the manga, the villains kidnap her and deliberately drown poor Akane in a Jusenkyo spring, creating the Spring of Drowned Akane. Fortunately, her experience with drowning is so extensive, she survived the ordeal. But it was still a surprisingly cruel reference to a character flaw that was always treated for comedy.
- In an episode of School Rumble Tenma (on behalf of her friends) challenges Nara and his buddies in a swimming competition. Since she knows she cannot swim herself, she expects that any of her friends will be able to win the competition (and the viewer may be led to believe that either Mikoto or Akira have better chances, at that). However, no sooner than they all dive, Tenma looks aside and sees... her three friends sinking behind her.
- Sonic X:
- In the first episode, Sonic falls into a swimming pool and tried to get out for several seconds to no avail.
- Even better, in the Sonic X episode "Sonic vs Knuckles", Sonic gets knocked into water by Knuckles. He instantly has a panic attack, splashing wildly and yelling. It takes him a few seconds to realise he's barely ankle deep, with Knuckles looking on at him with an annoyed look.
- In Sword Art Online, Suguha/Leafa, in spite of being the most athletically gifted player in reality, can't swim, so during a trip to the pool with other players, Asuna volunteers to teach her to swim. While she gets a hang of it in the real world, she needs help from the others to get to an underwater dungeon in Alfheim Online.
- Most Vampires in Vampire Hunter D cannot swim at all, and being submerged paralyzes them. And even D - a Dhampire of extraordinary caliber - can drown if he's in deep enough water to keep him immobile.
- Having grown up in an orphanage, neither Rinne or Fuka of ViVid Strike! ever learned how to swim. The rest of the cast teaches them during a minor subplot in the Beach Episode.
- In episode 4 of Yoake Mae Yori Ruri Iro Na, Feena jumps into a river to save a drowning puppy. However, since she grew up on the moon, and water is a scarce resource up there, she never learned how to swim, so Tatsuya ends up having to save her and the puppy shortly afterwards.
- Invoked and Exaggerated in Futaba-kun Change!. Misaki, the main character's love interest and a member of her school's swim team, has such a sweet tooth that the school pool has a high sugar water content from her sweat making it immensely dense. When the swim team swims in any other bodies of water with less density, the find themselves unable to swim in it.
- In Sonic the Comic, Sonic plays this trope straight. Towards the end of the comic's run, though, Sonic is shown to have overcome this weakness by taking swimming lessons off-panel.
- Archie Comics' Sonic the Hedgehog did this in reverse. This was mostly because the early comics was done with Rule of Funny in full effect and a lot of the game canon wasn't put in until later on.
- Wolverine can't float and can barely swim because of the dense metal covering his skeleton. Same goes for Colossus in his steel form, though he at least has the advantage of not needing to breath.
- Melaka Fray realizes by the end of the series that this is her Treacherous Advisor Urkonn's biggest weakness, and uses it to kill him. Possibly justified, since he is a demon.
- Nautilator has always been depicted as enthusiastic but completely incompetent in the water in all continuities of The Transformers comics. He rusts like a '67 Fiat, has the navigational skills of Roronoa Zoro, and in spite of being a giant living robot with an alternate mode made to traverse the ocean, he's been defeated by the tides changing. The Decepticons are hampered by just having him around. Inexplicably, the Decepticons made him part of their main underwater strike team. He does have a limited saving grace of accidentally finding valuable resources just about every time he gets stuck underwater, but that's not nearly enough to stop the rest of the Seacons from detesting being stuck with him.
- Klara Prast of the Runaways has explicitly stated that she does not know how to swim.
- In Outsiders, the Outsiders manage to stop an attempted invasion by Gorilla Grodd and his army by pushing the gorilla soldiers into the water - gorillas can't swim.
- In the Superman story arc The Dominus Effect, the Superman of 2999 cannot survive in water, as he nearly drowns to death when a torrent of water washes through Metropolis to put out the fire caused by the incendiary bomb used to take down the robots that have Turned Against Their Masters.
- In chapter 3 of the The Legend of Zelda fic Twisted Fates, Link saves Medli from drowning in the sea after she was knocked out of the sky by Seahats. As Medli explains, the Rito are meant to be in the air, not the sea, and thus none of them can swim.
- In Ariana Black, while swimming to escape an underwater base, Ariana gets caught up in completely mundane seaweed and drowns. And while magic doesn't work to revive her, CPR does.
- In Neither a Bird nor a Plane, it's Deku!, the Kaiju spawn that Izuku encounters on Korusan Island are completely incapable of swimming, recoiling after they touch water for the first time. Ironically enough, they have the appearance of a shark's head atop a pile of tentacles.
- Lilo & Stitch:
- Stitch is so dense that he will automatically sink if submerged in water. Of course, he ends up on an island. Doesn't stop him entering Hawaiian Surf Competitions.
- David in Unbreakable learns that along with his superhero-like strength, he has an Achilles' Heel of water. Justified in that David both has a fear of water due to a childhood incident, and in the context of the movie, his powers are ill-defined. David is vastly healthier than normal (never getting sick, and being vastly stronger than his size indicates), but no limits are recorded (he stops measuring his strength before finding his limit, and while he is the sole survivor of a massive train wreck, he balks at trying to see if he's bulletproof). Since humans can't exactly survive underwater, either, his "weakness" may simply be panicking from his childhood combined with still needing oxygen.
- Enola in Waterworld. Even though the entire Earth was covered with water decades or possibly centuries ago, this ten-year old girl can't swim. And people wonder why this movie bombed...
- In Superstar, Slater can't swim, and still doesn't bother to learn after he almost drowns and Mary Katherine saves him the first time.
- After being knocked off his boat, the killer in Terror at Tenkiller quickly drowns, despite being a marina worker. The Final Girl has no trouble swimming to shore.
- The famous 3-breasted cat-woman in Star Trek V: The Final Frontier. She leaps onto Kirk's back, is airplane-spun for a half-turn, then just gently tossed face-down onto a table where a variation of billiards is played, with a quarter-inch of water covering the playing field. She then just lays there, presumably insta-drowned.
- Played with in Robin Hood: Men in Tights. Robin Hood and Little John duel on a log bridge and are down to just slapping what's left of their shattered staves as if they were pencils. Robin gets the upper hand and boots Little John... into an itsy-bitsy stream, causing the man to flail and panic as if he's drowning. Robin can't help but look at the camera in disbelief before "helping" the man.
- The above is a parody of a scene in Robin Hood: Prince of Thieves which plays the trope straighter; Robin and Little John have a more dramatic stave fight which ends with Robin knocking John into an actual river... at which point he discovers John can't swim. Robin rescuing John earns John's gratitude and loyalty, and ends their battle.
- Leafie from Leafie, a Hen into the Wild was a caged hen for most of her life, so she can't swim. This is noted several times by other characters. This causes problems as her son is a duck, who has a natural affinity for water. Leafie nearly drowned trying to "save" Greenie when he was a baby. The other duckings mock Greenie for having a mother who can't swim.
- A line from Maui's "I Am" Song in Moana suggests that he is this trope. Since he is a demi-god of the sea and he was stuck on an island for a thousand years, he's likely not joking.
Maui: "And I'm gonna need that boat/I'm sailing away, away/You're Welcome!/Cause Maui can do anything but float!"
- Film "Billion Dollar Brain"; Thinking that his agents in the Soviet Union have successfully spread a debilitating virus, General Midwinter leads his private army in a charge across the frozen Gulf of Finland, intending to invade (and "liberate") Latvia; however, his "agents" never existed: and a Soviet Airforce bomber drops a massive "Blockbuster" bomb on the ice; and the entire army, including the General, die horribly, in an "hommage" to Sergei Eisenstein's "Alexander Nevsky".
- The Last Leprechaun: Tommy has to save Finn from drowing in a tub of water.
- Garion had acquired this skill ever since he was hit by a log on a pond while attempting to swim.
- in Cheaper by the Dozen, Mother sinks like a rock every time that Dad tries to teach her how to swim. The failures are so frequent and so complete that at one point Dad accuses her of deliberately resisting.
"Mercy, Maud," Mother sputtered. "Mercy, mercy, Maud. Do you think I like it down there in Davey Jones' locker?""Davey Jones' locker," scoffed Dad. "Why, you weren't even four feet underwater. You weren't even in his attic."
- In Fairy Dust And The Quest For The Egg by Gail Carson Levine, it is mentioned that if a fairy's wings got wet, they'd become heavy and drag the fairy underwater.
- Dwarves in the Dragonlance series are noted for swimming like stones.
- It becomes a running joke in Aubrey-Maturin that Doctor Stephen Maturin would always nearly drown when trying to board a ship. Considering how often he needs to go on and off ships as the Naval Surgeon...
- In the Green-Sky Trilogy, Raamo slipped and fell into the Bottomless Lake and made no effort to try and swim or even let go of the "tool of violence" he was carrying. Snyder, realizing she really screwed up with this ending, authorized what was likely the first canonical video-game sequel to another medium's story...and even in that game, so much as touching the water would send the player back to their home with an ominous "You were found unconscious" message.
- Septimus Heap:
- Septimus near-drowns surprisingly quickly in after he's been thrown into the water by Queen Etheldredda.
- In the end of the book, Etheldredda drowns very quickly as well after she's slid into the river.
- In the Guardians of the Flame series, dwarves are noticeably denser than humans, with the result that they sink like a stone in water. This leads to a panic-inducing incident in one book when the dwarven member of the cast is tossed off a ship in the middle of a battle, with no one available to rescue him. Fortunately the ship is anchored, and he manages to get to the anchor chain and climb up it before drowning.
- In Edgar Rice Burroughs Martian books, very few Martians know how to swim, because Mars has very few deep bodies of water.
- This figures into Augustus Gloop's undoing in Charlie and the Chocolate Factory — according to his mother "He can't swim a yard", so when he tumbles into the chocolate river he can only flail and call for help before getting sucked into a pipe, which saves him from drowning but turns out to be a case of Out of the Frying Pan.
- In Smallville, Lana manages to drown in less than 15 seconds. Don't worry, Clark saves her with some mouth-to-mouth.
- In RuPaul's Drag Race, one challenge involved an underwater photoshoot, but not all the drag queens could swim. Hilarity ensued.
- In Lost, Sayid manages to drown beyond resuscitation about 5 seconds after he stops struggling.
- In one Korean Drama (I believe it was called Hi School: Love On), a character was helping another get a pendant they had lost in the pool. They wound up flailing about trying to swim, until another character told them to stand up.
- In the Quantum Leap episode The Wrong Stuff, the episode's antagonist falls into a water-filled ditch that can't be more than three or four feet deep, and Sam has to save him from drowning. This rescue naturally leads to the antagonist's change of heart, which resolves the episode's conflict.
- In Lexx, Kai is too dense to swim as a result of the decarbonization process that made him an immortal undead assassin. In Season 3 which alternates between a water world and desert world, falling into the ocean wouldn't destroy him, but he'd be stuck a hundred kilometers underwater til the end of time.
- Klay World:
- Parodied in "Glass of Water", where a bunch of klaymen drown in a tiny puddle produced by a glass of water by sticking their faces in the puddle. And then several more are drowned by the towel used to clean up the puddle.
- In "Swimming Pool", one of the Klay Men decides to jump off a diving board into the swimming pool. However, being made of clay, he immediately sinks and drowns. It doesn't help that the lifeguard does absolutely nothing to help him.
- In Cracked:
- Landscapes That Murder You all but names this trope when describing the Bolton Strid (see Real Life below):
It's exactly how water works in a video game: It looks all stupid and harmless, but the second your foot touches the surface, you get some bullshit drowning animation and die instantly.
- The #16 Science Lesson As Taught by Famous Video Games is that Altair + H2O = death.
- Landscapes That Murder You all but names this trope when describing the Bolton Strid (see Real Life below):
- The Most Popular Girls in School: Trisha nearly drowns in the season 5 premier... in the shallow end of the pool... while wearing water wings... despite being a rather tall teenage girl. Mackenzie has to try to fish her out of the water with a hook, before Trisha realizes she can Stop Drowning and Stand Up. And apparently, this isn't the first time this has happened.
Trisha: Well, I'm going to go for a dip in the pool.
Brittnay and Mackenzie: (immediately) Stay in the shallow end!
Trisha: (exasperated) I KNOW!
- DSBT InsaniT: Water doesn't put Fire Guy out, he just can't swim!
- Robo won't short-out in water, he just can't swim.
- In Code Lyoko, any monsters or heroes falling into the Digital Sea are "permanently virtualized", i.e. dead. Happened to a lot of monsters, and to Yumi and Aelita once each (they got better). There are also ordinary bodies of water in some sectors; terrestrial monsters just sink and drown there, but the heroes can swim through them.
- Spongebob Squarepants: Neither Spongebob nor Patrick know how to swim in Goo Lagoon. At first this sounds like a winking nod to the shows liberal use of the Water Is Air trope, until you remember sponges and starfish can't swim in real life either. They crawl.
- Panthro from ThunderCats (2011) is a master of this technique.
- Fry from Futurama, especially at the beginning.
- Codename: Kids Next Door: Numbuh 4. He later learns how to swim, but he's still not good at it and prefers to avoid it if possible. This actually ends up being a plot point in an episode: Numbuh 1 realizes the utopian island he crashed into is a simulation because Numbuh 4 is swimming at a pool party
- Hey Arnold!: Lila.
- Avatar: The Last Airbender: Toph mostly compensates for being blind by sensing vibrations through the ground. This doesn't work in water, so she never learned to swim.
- The Bumble in Rudolph the Red-Nosed Reindeer sinks like this.
- In an episode of American Dragon: Jake Long, Jake meets a mermaid named Silver who can't swim because she's hydrophobic. She gets better, though.
- Dragon Hunters: Gwizdo. As a pilot among the flying islands, he doesn't remember about this skill until it suddenly becomes a matter of life and death. And even after, he prefers to not care about it, while his lifestyle of traveller gives a lot of chances to improve the situation with Lian-Chu's support.
- Hawk in A.T.O.M. (at least, in first season).
- Adolescent Shimiwe, from Inami, french cartoon about Amazonian tribes. This case resulted in a lot of problems, because the river was always near.
- Some accounts of Fredrick I, the Holy Roman Emperor actually have him falling face-down in plate armour into a shallow part of a river and, you guessed it, drowning. Justified in that plate armour is not recommended swim-wear, it's extremely heavy, though it's a myth that armored knights could barely move around in it as it's well distributed. That said, falling off a horse is dangerous, moreso when you've got an extra 60 pounds on you. There are myths of knights drowning in puddles, but if that happened, they were likely concussed first. The whole incident may also be a simple myth that never actually happened.
- There have, however, been instances where Knights fell into mud and were trampled by others in the charge, causing them to drown that way.
- It should also be pointed out that Fredrick's fatal drowning occurred just immediately AFTER a hard battle with Turks and he was so severely dehydrated that he was scrambing the area around for water. In fact when he did drown, he was recklessly paddling into the water without even observing it depth first. Some accounts even describe him as going deeper and deeper into the water while attempting to kneel to get some with his hands to drink until he unknowingly went so deep that he simply fell in. Even accounts of death in a relatively shallow parts of the river admit the king's frenzied state, worn physical body, and accidental tripping in the drowning. So its not the water itself alone that killed him but an exhausted state of mind and body was the main catalyst.
- Some historians even state that he was suffering from symptoms of cardiovascular disease and other conditions associated with old age during this campaign and the drowning may not even have killed him but a sudden fatal stroke or heart attack.
- The Battle of Lake Peipus in Lithuania in 1242 saw this trope played out on the grand scale. Prince Alexander Nevsky's lightly-armed Novgorodian soldiers drew an army of impetuous German knights out onto a frozen lake where they were at a disadvantage. Not only did the western crusaders find it hard to keep their footing, the Novgorodians lured them to a section of the lake with thinner ice that could not take the weight of Teutonic Knights in full armour.
- In at least one episode in WW2, light Russian tanks crossed frozen rivers, daring German pursuers to do the same. But a Tiger tank weighed in at fifty tons as opposed to twenty-two...
- Modern soldiers are known to drown because of the encumbrance by their combat gear. Many soldiers and marines landing on Normandy or various Pacific islands during World War 2 were killed for this reason. Even in 21st century, training for operations in water while wearing full military gear is considered among the toughest exercise for soldiers.
- And in Normandy, field marshal Rommel's plan to secure the area against an invasion included deliberately flooding vast parts of the hinterland as a defense against airborne troops. For paratroopers, who have to carry all their equipment themselves and would often get entangled in their parachutes when landing, those artificial marshes were formidable deathtraps - and in fact a large number of them drowned.
- Additionally, in the battle of Passhendale (WWI), the ground was so soggy due to heavy rains that many soldiers literally drowned in soft mud (and in rain-filled shell craters, which provided unexpected large pockets of water, virtually undetectable underneath the overall coverage of ankle-deep sludge).
- Gorillas cannot swim. This was even referenced in the remake of Planet of the Apes.
- This applies to pretty much all of the great ape species aside from humans. In addition to a more tall, thin body design (granting a more efficient stroke), humans have a higher percentage of body fat and larger lungs in proportion to mass than other large primates, giving them greater buoyancy. Humans are still poorly equipped for swimming in comparison to many mammals, and very skinny humans often have trouble swimming efficiently because their legs and feet tend to sink. Humans still have remnants of the mammalian diving reflex, but it isn't very helpful most of the time.
- Another reason is gait: most mammals are quadrupedal, and even with no prior swimming experience a mammal that falls into a body of water will attempt to mimic the gait it uses on land. That's why quadrupeds like horses, elephants, tigers, bears, and rats are able to swim, and why dogs are able to "doggy paddle." Great apes are not quadrupedal, so their response is less "a walking motion that translates to paddling" and more "flailing and drowning."
- Chimpanzees and orangutans can swim. They do so for fun.
- Before actual swimming techniques were developed, a lot of people could easily commit suicide by wading into a lake until the water level went over their heads.
- Pirates avoided learning how to swim to avoid a drawn out death, not that you could expect other sailors to know how to either.
- The Bolton Strid in Yorkshire, England, part of the River Wharfe and not part of any family of murdering Trolls. It may look like a gentle brook, but it holds the amount of water one would expect from an enormous, raging river being squeezed like a tube of toothpaste by the local geology. How? The river's really deep, for all it's not that wide, making the flow really intense below the calm-looking surface. The result? It has an unusually high lethality rate... as in, 100% deadly. Yes, that means falling in is a very, very bad idea, forget deliberately going for a dip. You'll be lucky if your body even shows up downstream.
- Giraffes are one of the few non-primate mammals that have no ability to swim, thanks to their high center of gravity and extremely long legs. However this isn't much of a hindrance for them as their height means they have an easy time finding places shallow enough for them to walk across a river.
- Ironically enough, despite being an aquatic animal, the common hippopotamus is an extremely poor swimmer. Its bones are so dense that it sinks in water; instead of swimming it walks across the bottom, then hops to the surface when it needs to breath. This limitation means that it's restricted to fairly shallow rivers and lakes.