What is the purpose of having a butt?

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?

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.

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.

Mmmmmm…butts… :drools:
[/homer]

Spankings wouldn’t be nearly so much fun for either party if we didn’t have one.

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.

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.

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.

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).

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.

Speak for yourself.

:smiley:

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.

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Band name!!

(OK, I know this is old by now, but I’ve never spotted one before)
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There’s even a word for it.

AFAIK the butt has two purposes:

  1. It has the muscles that make walking/running easier.
  2. To give Jennifer Lopez a career.

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 reason we have butts. Evolutionary biology in a nutshell.