Why are humans such better swimmers than all our primate cousins?

[BrokenBriton]

We’re the only apes who go to swimming lessons.

[Thudlow_Boink]

@Mr.Kobayashi

but prompts the question

Off topic, but I just wanted to thank you from the bottom of my heart for not (mis)using the phrase “begs the question” here.

[Si_Amigo]

Apes cannot rock a two piece thus they don’t go near the pool.

[Sparky812]

@Turpentine

I don’t buy the fat floats=good swimmer thing. Olympic swimmers are usually like, 4% body fat and that doesn’t seem to cause them problems. Obese people aren’t better swimmers than average people.

That’s because fat floats ≠ good swimmer, fat floats = more buoyancy which makes swimming a whole lot easier.
If you don’t believe me, look at the body fat of whales, walruses, seals, manatees, sea lions, etc.

Your analogy to Olympic swimmers does not …errr…hold water either.
Compare a jet and a hot air balloon, Which is a better flyer?

[John_Mace]

@ralph124c

Because we are on a totally different evolutionary path from the great apes.

THere is no such thing as an “evolutionary path”. Terms like that are what make people think evolution is directed.

Our bodies have little hair…we have bigger brains, and we have fully opposed thumbs.

What does any of that have to do with swimming? The only one that makes sense is our brain, since we learn to swim.

We are totally different in design. Most of the primates fear water; we seem designed to be in it.

Ugh, please don’t use “design” wrt evolution unless you are very clear about what you mean. But let’s keep in mind that people who never learn to swim are prone to drowning, so it’s pretty clear we did not evolve as swimmers.

I was always a pretty good swimmer, but I never actually learned good technique until I was an adult. I can tell you, there is nothing natural about good technique. It’s not something that is easy to learn.

[drastic_quench]

@MichaelEmouse

Having a lot of fur seems not to mix well with swimming.

Also, I get the impression that we have rather long legs compared to other apes. Perhaps our upright posture also allows us to use our legs well to propel us.

Long legs aren’t an advantage in swimming. The best Olympic swimmers, like Michael Phelps, have a long torso and short legs. So it can’t be the legs.

I don’t see how it could be posture either. Apes look built to doggy paddle, second only to dogs.

[Lightray]

@Sparky812

That’s because fat floats ≠ good swimmer, fat floats = more buoyancy which makes swimming a whole lot easier.
If you don’t believe me, look at the body fat of whales, walruses, seals, manatees, sea lions, etc.

The body fat of whales, walruses, seals, manatees, sea lions, etc. is not there to aid buoyancy. It’s to insulate against heat loss – water is a much more efficient conductor of heat than air, and mammals who spend most of their time in the water need the insulation.

For flotation, all they’d need is to be neutrally buoyant or nearly so. Most humans are neutrally buoyant (well, most women are; men tend to be negatively buoyant). Sea mammals have proportionally much higher fat than they need for their buoyancy.

[MichaelEmouse]

Alright, looks like I was wrong.
So, it looks like it’s a question of range of movement, evolved for something else but which happens to be useful for swimming?

Also, as has been said previously, people who don’t learn how to swim are prone to drowning. It could be that our brains yet again allow us to do things for which we have suboptimal bodies. We swim well compared to other apes because our brains enable us to learn and teach how to swim. The social element of teaching the young how to do it under supervision means they don’t have to figure it out by trial and error which is particularly important when error can be fatal.

[Sparky812]

@Lightray

The body fat of whales, walruses, seals, manatees, sea lions, etc. is not there to aid buoyancy. It’s to insulate against heat loss – water is a much more efficient conductor of heat than air, and mammals who spend most of their time in the water need the insulation.

For flotation, all they’d need is to be neutrally buoyant or nearly so. Most humans are neutrally buoyant (well, most women are; men tend to be negatively buoyant). Sea mammals have proportionally much higher fat than they need for their buoyancy.

You miss the point.
I’m not suggesting that that body fat is there primarily to aid buoyancy.
I’m stating that as a result of their higher body fat content they are more buoyant than those without, which facilitates swimming by reducing the amount of force and energy required to stay afloat and generate propulsion.

[Colibri]

@Sparky812

I’m stating that as a result of their higher body fat content they are more buoyant than those without, which facilitates swimming by reducing the amount of force and energy required to stay afloat and generate propulsion.

Excessive buoyancy is not necessarily a good thing if you need to dive. Bottom-feeding marine mammals like manatees have relatively dense bones to enable them to stay down. However, for most marine mammals neutral buoyancy is better than positive buoyancy so they can move freely in search of food.

[Sparky812]

@Colibri

Excessive buoyancy is not necessarily a good thing if you need to dive. Bottom-feeding marine mammals like manatees have relatively dense bones to enable them to stay down. However, for most marine mammals neutral buoyancy is better than positive buoyancy so they can move freely in search of food.

Agreed.

FTR I’m talking about relative buoyancy not necessarily positive vs. negative.

[Dana_Scully]

@Ethilrist

Tell that to the seals, muskrats, beavers, sea lions…

They aren’t primates, which is what’s being talked about here.

[Der_Trihs]

@Washoe

A chimp in water will sink like a rock. They actually have an innate fear of large bodies of water, rivers, and even moats. It’s all due to body fat. Chimps have none.

They also have denser muscles and as said less fat, so are more prone to sinking. However; the few chimps that do learn to swim can do so as well or better than humans; they just have to use their superior strength to paddle harder to stay afloat.

I’d say that it’s learning to swim that’s the main hurdle for apes. Once they learn they appear to do fine; but if there’s one thing we do better than other apes, it’s learn.

[Lightray]

@Sparky812

You miss the point.
I’m not suggesting that that body fat is there primarily to aid buoyancy.
I’m stating that as a result of their higher body fat content they are more buoyant than those without, which facilitates swimming by reducing the amount of force and energy required to stay afloat and generate propulsion.

No, I didn’t miss the point. The point was wrong. As Colibri notes, buoyancy isn’t that important to aquatic animals – neutral buoyancy is. Which is why I said that’s all they’d need. And almost half of all humans aren’t neutrally buoyant – they’re negatively buoyant. Like apes.

[Sparky812]

@Lightray

No, I didn’t miss the point. The point was wrong. As Colibri notes, buoyancy isn’t that important to aquatic animals – neutral buoyancy is. Which is why I said that’s all they’d need. And almost half of all humans aren’t neutrally buoyant – they’re negatively buoyant. Like apes.

Nope, you still missed it.

[Colibri]

@Sparky812

Nope, you still missed it.

Maybe you better restate it because I missed it too. Your (apparent) contention that fat makes animals better swimmers is wrong as stated.

[QUOTE=Dana Scully]
They aren’t primates, which is what’s being talked about here.
[/QUOTE]

Ethilrist was addressing the point about mammals with fur not being good swimmers, which is wrong.

[the_diego]

Yeah, how come I haven’t heard of a chimp swimmer? Doesn’t sound too hard to train.

[Colibri]

Regarding the swimming ability of apes, here are some posts I made on the subject in the first thread I ever responded to here, Re: Can camels swim?

@Colibri

Psychological factors may in fact have something to do with the apparent inability of the Great Apes to swim, even though they are anatomically so similar to humans. In “The Apes,” (Vernon Reynolds, 1967, pp. 87-88) we find the following rather definite statements:

“Swimming ability is almost nil in the apes. A young gibbon that fell into a pond at a zoo drowned while its mother watched, too afraid to rescue it. No report of swimming by a gibbon exists, but several others confirm its inability to swim. Orangutans have never been observed swimming, and probably cannot. Gorillas, faced with the alternative of capture by man, dare not go into water more than two or three feet deep. They have never been observed to swim, and at least one mature male has drowned in a zoo water enclosure, sinking as soon as he fell in. Only in chimpanzees is there some evidence for swimming ability. [Reynolds then cites a report of four chimpanzees seen swimming across a river in Africa, but then says he is inclined to think it must really have been some other species.] In captivity, attempts to teach chimpanzees to swim have met with failure, and deepwater barriers have often proved efficient in keeping apes on islands, as for example at the Paris Zoo. The general response of chimpanzees to water is universally agreed to be one of avoidance and even fear. I have myself on two occcasions helped pull chimpanzees out of a water-filled moat in which they were quite clearly drowning, and I am convinced they cannot swim, although in their stuggles as they flounder about they can sometimes make a little headway in the water.”

@Colibri

PS. As a follow-up to my previous post, the case of the “drowning gorilla” mentioned in many references seems to be based on an incident at the Bronx Zoo in the late '40s or early 50’s, when a full-grown adult male gorilla tumbled into the moat of his enclosure and drowned with scarcely a struggle in full view of a crowd of horrified and astonished spectators. When I find out the name of the gorilla, I’ll let you know.

@JillGat

Still waiting for the name of the gorilla… Jeez, get with the program here, Colibri.

@Colibri

Patience, Jill, patience. These things take a little time.

The name of the gorilla was Makoko, and the incident happened in 1951. The moat was six feet deep. (ref: Maple and Hoff, 1982, Gorilla Behavior, p. 236.)

The obituary mentioned that “the family requests bananas be sent in lieu of flowers.”

Sorry this took so long.

[QUOTE=C K Dexter Haven]

Of course, there is a danger in generalizing about a species from one sample of the species.
[/QUOTE]

@Colibri

True, CK, but the unfortunate Makoko is only one example of many (if perhaps the most famous one). I have also seen cited a case where no fewer than four chimpanzees drowned at a single facility in moats or small pools over a relatively brief period of time. ALL the technical and popular literature I have checked (and at this stage it’s a lot) is absolutely universal in the opinion that swimming ability in all the apes is at best minimal. Most state unequivocally that apes (gorilla, chimpanzee, orangutan, and gibbons; many monkeys, including some that are informally called “apes” can swim well) do not swim. The more cautious authors will say “appear to be unable to swim,” while some will venture the opinion that “perhaps young ones could be trained to swim,” although the experiment seems to have been made often and I have never seen a citation of a success.

The only specific citations for swimming apes I have seen so far have been (1) the four chimps dog-paddling across a stream in Equatorial Guinea I mentioned in a previous post, but considered as doubtful by Reynolds; and (2) a pet orangutan that was lured aboard a steamer in an attempt to “kidnap” it from its owner. When the steamer pulled away from the dock, the ape jumped overboad and managed to make it to shore. Ever afterward he would flee to the jungle whenever a steamer was in town. But he seems to have been the veritable Johnny Weismuller of anthropoids. (Please do not ask me the name of the orangutan. I can probably find out, but I don’t have the time right now.) And as you say a single example does not make a case.

This is quite mysterious, as I said, because apes are anatomically so similar to humans. Occasionally someone will speculate about a physical cause, such as the “center of gravity (OK, mass)” argument, or that apes may have low body fat. But while the “center of gravity” argument could conceivably apply to an adult male gorilla, in which the heavily-muscled shoulders could force the muzzle under, I don’t see how it could apply to a young chimp. The body-fat argument is slightly more plausible, as it is often mentioned that a drowning ape “sank like a stone.” However, many captives, at least gorillas, are obese and should be able to float. I have seen no general data on body-fat percentages to back this contention, and I think people are just grasping at straws.

What seems to be the case is that apes are simply psychologically averse to water, at least deep water, and when they fall in or are placed in it they just go bonkers and thrash around helplessly until they drown (or sometimes don’t even struggle). This happens even if they are only a few feet from shore. There are few healthy adult humans, even non-swimmers, that would not be able to rescue themselves in such circumstances, but apes very often don’t. There are any number of anecdotes in the literature of owners placing a gibbon, orang, or whatever (usually young, but sometimes adult) in the water as an experiment and then having to rescue it when it became distressed and started to go under.

Some young gorillas will play in a basin of water, but others seem to be afraid of it. On the other hand, virtually all human babies will play happily in a pool. And apes in nature seem to be averse to crossing even shallow water; in “The Mountain Gorilla” George Schaller mentions that they will usually cross even small streams on fallen logs to avoid wading.

Distribution also argues that apes rarely if ever cross water. The range of the Eastern Lowland Gorilla is circumscribed by the Niger and the Congo (Zaire), while the Western Lowland Gorilla is found a great distance away at the headwaters of some of the Congo tributaries. The ranges of the eastern and western subspecies of Common Chimpanzee is likewise split by the Niger, and Common Chimps are not found south of the Congo. The Pygmy Chimp (Bonobo), usually considered a difererent species, on the other hand, is restricted to the south side of the Congo. While Orangs occur on the larger islands of Indonesia, they seem to have been isolated there by rising sea levels after the Pleistocene. And the ranges of some gibbons seem to be limited by major rivers in Southeast Asia.

So there you have it. There seems to be a mountain of evidence, both anecdotal and experimental, that if apes swim at all, it is only under the most extraordinary circumstances. They have rarely if ever been observed to swim in nature; in captivity they often drown in pools of water only a few feet wide; and when experimentally placed in water they show great distress and usually have to be rescued. While I would not totally rule the possibility that one could be taught to swim with persistent effort, I have so far seen no reports that this has ever been done.

Why this might be so is extremely puzzling. Since monkeys swim, apes must have lost this ability at some point; and humans somehow regained it. But we definitely seem to be an oddball in our little branch of the family tree.

[QUOTE=Colibri]
PS. In my last post I inadvertently switched the ranges of Eastern and Western Lowland Gorillas. Sorry.
[/QUOTE]

[QUOTE=JillGat]
Well, duh.
[/QUOTE]

@Colibri

What we really haven’t discussed yet is the basis for the apparent difference between apes and humans in swimming ability. Is human swimming ability entirely learned, or is there evidence for some innate ability?

At least for adults and older children, humans show little more instinctive swimming ability than apes; an adult or toddler that has never learned to swim will usually quickly drown in deep water (although as I remarked earlier possibly able to save him/herself in circumstances where an ape would drown, such as in a narrow moat; but this could be due more to intelligence than instinct).

On the other hand, I have heard that very young human infants, pre-walking, will swim, apparently instinctively, when placed in water. Can anybody confirm/contradict this? If so, it would be very interesting. If it exists, at what age is this ability lost?

While I stated earlier that even young apes appear to be unable to swim, I doubt that the experiment has ever been made on a very young ape. It would simply be too risky to place a valuable infant gorilla or chimp in the water.

[Xema]

@Dana_Scully

They aren’t primates, which is what’s being talked about here.

Ethilrist’s post was on target - it supplied counterexamples in response to a post that suggested fur was a detriment to swimming ability.

[Sparky812]

@Colibri

Maybe you better restate it because I missed it too. Your (apparent) contention that fat makes animals better swimmers is wrong as stated.

FTR, I never stated that it makes them better swimmers, I said that it makes swimming easier.

Quote:
Originally Posted by Turpentine [

](http://boards.straightdope.com/sdmb/showthread.php?p=16546981#post16546981)
I don’t buy the fat floats=good swimmer thing. Olympic swimmers are usually like, 4% body fat and that doesn’t seem to cause them problems. Obese people aren’t better swimmers than average people.

Which is completely false.
Olympic swimmers actually have higher average body fat than other athletes, approx. 15-20% as opposed to say 4-5% for runners.

It’s simple physics, due to their higher density, swimmers with little body fat must work harder to stay afloat in water.

Is it the only criteria for determining who is a better swimmer? No.
But you can’t discount that buoyancy is a key factor, especially when you’re talking about non-aquatic mammals who may or may not be able to swim at all.

Basically, it’s sink or swim.