# What is the purpose of having a butt? **URL:** \ **Category:** Factual Questions\ **Created:** [March 14, 2003, 7:01am UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282 "2003-03-14T07:01:24Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Incubus](https://avatars.discourse-cdn.com/v4/letter/i/c68b51/32.png) [@Incubus](https://boards.straightdope.com/u/Incubus)\ **Post date:** [March 14, 2003, 7:01am UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/1 "2003-03-14T07:01:24Z")
Why do we have a butt? If its for sitting, then why do other animals who do plenty of sitting (dogs/cats) lack a true butt? What biological advantage is there to having this cleft running down our rear end? ---
**Author:** ![Thaumaturge](https://avatars.discourse-cdn.com/v4/letter/t/858c86/32.png) [@Thaumaturge](https://boards.straightdope.com/u/Thaumaturge)\ **Post date:** [March 14, 2003, 7:05am UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/2 "2003-03-14T07:05:46Z")
Other animals do indeed have butts…look at horses. It’s simply two muscles, animals that have especially strong leg muslces tend to have more prominant butts. The cleft is just because of the way muscles attach to the spine. ---
**Author:** ![CrazyCatLady](https://avatars.discourse-cdn.com/v4/letter/c/dfb087/32.png) [@CrazyCatLady](https://boards.straightdope.com/u/CrazyCatLady)\ **Post date:** [March 14, 2003, 7:12am UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/3 "2003-03-14T07:12:36Z")
Define butt. Are you talking about gluteal muscles, or are you talking about glutes that stick out? Our butts stick out mainly because we walk upriight. Bipedal locomotion calls for more developed gluteal muscles to move a leg back and forth. Also, our glutes tend to protrude less when we’re on all fours like dogs and cats. (Their muscles are also attached with somewhat different spatial arrangements, which also keeps them from sticking out.) As for the gluteal cleft, each set of glutes moves one leg. They have to be seperate from each other to move the legs seperately. ---
**Author:** ![Gorsnak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gorsnak/32/7587_2.png) [@Gorsnak](https://boards.straightdope.com/u/Gorsnak)\ **Post date:** [March 14, 2003, 7:20am UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/4 "2003-03-14T07:20:13Z")
Mmmmmm…butts… :drools: [/homer] ---
**Author:** ![Zenster](https://avatars.discourse-cdn.com/v4/letter/z/cdc98d/32.png) [@Zenster](https://boards.straightdope.com/u/Zenster)\ **Post date:** [March 14, 2003, 7:25am UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/5 "2003-03-14T07:25:30Z")
> [@](#): > > \*Originally posted by Incubus \* > Why do we have a butt? Spankings wouldn’t be nearly so much fun for either party if we didn’t have one. > [@](#): > > If it’s for sitting, then why do other animals who do plenty of sitting (dogs/cats) lack a true butt? They have butts, they’re just nowhere near as noticable or attractive as human butts can be (at least women’s). Plus, dogs and cats have worn theirs down with all that licking. > [@](#): > > What biological advantage is there to having this cleft running down our rear end? It not only provides the “working man’s smile” but is an ideal location for a sphincter. Where would you have it? Under one of your arms? Think of your deodorant costs. What in Hades would _your_ toilet look like and don’t let’s even think about shaving there. ---
**Author:** ![Skip](https://avatars.discourse-cdn.com/v4/letter/s/ebca7d/32.png) [@Skip](https://boards.straightdope.com/u/Skip)\ **Post date:** [March 14, 2003, 8:12am UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/6 "2003-03-14T08:12:17Z")
Also they are an ideal place to store fat. The San people of South Africa (commonly called the Bushmen) have very pronounced derrieres as that is where a lot of their body fat is stored. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [March 14, 2003, 12:55pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/7 "2003-03-14T12:55:00Z")
As noted above, a buttock is needed for the powerful muscles needed to keep us upright. Other developments are secondary. Having your anal sphincter there isn’t “convenient” – it’s inconvenient. Man is the only animal that uses toilet paper, or needs to. Men are attracted to a shapely female bottom (and women to men, my wife tells me) because it’s programmed in, and probably because it is an indicator of good health in the potential mate, but we could’ve been programmed for some other shape just as easily had evolution gone some other way – there’s nothing intrinsically aesthetic about a butt. I remember Graham Kerr explaining the need for a buttock on his first TV show, “The Galloping Gourmet”. He stood well back from the camera and moved his leg so that you could see the muscle was necessary. That necessary concentration of muscle results in good eating – Hams and butt roasts and even crab (the point of Kerr’s demonstration – he was cooking crab that day and wanted to explain why there was so much good crab meat there). Few animals have walked upright. Dinosaurs did it, but they developed a large, heavy counterbalancing tail, often with a “corset” of cartilage and tendon to keep it outstretched. No butts on T. rex. Birds stand upright, too, without the tail, and I don’t know how they do it. Jusrt about everything else only stands up temporarily – apes, meercats, performing bears, etc. – and don’t need a permanent butt. (So forget those Charmin commercials with the big-butt bears). ---
**Author:** ![istara](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@istara](https://boards.straightdope.com/u/istara)\ **Post date:** [March 14, 2003, 1:13pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/8 "2003-03-14T13:13:18Z")
I think of those monkeys (sacred monkeys?) where the females’ butt swells up all red and bulbous, IIRC when she is in season/fertile. They always look incredibly painful. The purpose must be to signal mating readiness to a mate, useful no doubt, but I am glad that homo sapiens butts don’t do the same. ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [March 14, 2003, 5:50pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/9 "2003-03-14T17:50:00Z")
Speak for yourself. ---
**Author:** ![scout1222](https://avatars.discourse-cdn.com/v4/letter/s/34f0e0/32.png) [@scout1222](https://boards.straightdope.com/u/scout1222)\ **Post date:** [March 14, 2003, 5:58pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/10 "2003-03-14T17:58:04Z")
😃 ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [March 14, 2003, 6:33pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/11 "2003-03-14T18:33:11Z")
> [@](#): > > The purpose must be to signal mating readiness to a mate, useful no doubt, but I am glad that homo sapiens butts don’t do the same. Human beings don’t go into seasonal estrus, so they’re effectively swollen all the time – humans are always fertile (year-round, within the limits of their periods), and so are always sexually attractive. Although swollen chimp butts look painful (not to mention asymmetrical), I’m sure they feel ultra-sexy to their possessors, and irresistably sexy to male chimps. ---
**Author:** ![TaxGuy](https://avatars.discourse-cdn.com/v4/letter/t/b19c9b/32.png) [@TaxGuy](https://boards.straightdope.com/u/TaxGuy)\ **Post date:** [March 14, 2003, 6:55pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/12 "2003-03-14T18:55:14Z")
[hijack] > [@](#): > > \*Originally posted by CalMeacham \* > swollen chimp butts Band name!! (OK, I know this is old by now, but I’ve never spotted one before) [/hijack] ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [March 14, 2003, 7:15pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/13 "2003-03-14T19:15:15Z")
> [@](#): > > \*Originally posted by Skip \* > \*\*Also they are an ideal place to store fat. The San people of South Africa (commonly called the Bushmen) have very pronounced derrieres as that is where a lot of their body fat is stored. \*\* There’s even [a word](http://www.m-w.com/cgi-bin/dictionary?va=steatopygias) for it. ---
**Author:** ![Meatros](https://avatars.discourse-cdn.com/v4/letter/m/b4bc9f/32.png) [@Meatros](https://boards.straightdope.com/u/Meatros)\ **Post date:** [March 14, 2003, 7:26pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/14 "2003-03-14T19:26:32Z")
AFAIK the butt has two purposes: 1. It has the muscles that make walking/running easier. 2. To give Jennifer Lopez a career. ---
**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\ **Post date:** [March 14, 2003, 10:39pm UTC](https://boards.straightdope.com/t/what-is-the-purpose-of-having-a-butt/161282/15 "2003-03-14T22:39:30Z")
It’s been my observation that J. Lo has divested herself of her rather nice butt since hooking up with B. Fleck. Come on. I only know that because TheLadyLion subscribes to _People_ and sometimes there’s nothing else to read in the crapper. > [@](#): > > _The wise and all knowing [Lore Sjöberg](http://www.brunching.com) says:_ > **Dimetrodon > Looks like a gecko with a mohawk. Big sail on its back that they think attracted mates or conserved body heat. Actually, that’s what scientists say about anything on an animal they don’t understand. They could find evidence of an iguanadon with a ZZ Top beard and they’d say “the beard was probably to conserve body heat or attract mates.” Which, come to think of it, is probably what ZZ Top uses them for. Anyhow.** The reason we have butts. Evolutionary biology in a nutshell.