Why do people have butt cracks? What evolutionary purpose does it serve?

Question

Seriously! Why? No other animals have butt cracks! And it seems to just get in the way, forcing us to wipe the remainder of our waste away.

Also, is it safe to assume that the the self awareness and physical ability needed to wipe ones own bum came BEFORE the evolution of the butt crack? I mean, if the butt crack came first, the early humans would smell poorly, and probably never reproduce, because everyone is disgusting.

Are there any other animals with butt cracks?

And here's the important question. Why did I wake up at four in the morning this morning wondering about the evolution of butt cracks?

Answer 1

Humans do indeed have the biggest butt cracks, and the North American diet tends to make ours biggest and flabbiest of the big, flabby butt cracks, leading to the problems of hygiene mentioned.

There are other animals that have pretty sizable butt cracks though. Rhinos and hippos come to mind. They're not the cleanest critters around either.

The human butt crack, from an evolutionary perspective, is the legacy of our development of a bipedal stance. In order to maintain bipedalism, the structure and position of our pelvis has changed from the ancestral pelvis orientation (most similar to the modern chimpanzee). Along with these changes came modifications to the proportions of our butt muscles. On humans, the gluteus maximus is the largest muscle of our butt. It is involved in maintaining our position, as well as assisting in leg extension actions while walking or running. It is the globes of the gluteus maximus that make up the majority of our butt crack problem.

In non-bipedal primates, such as chimps and gorillas, the gluteus maximus is much, much smaller, and they do not have the butt crack situation we do. These primates do have other adaptations however. Most non-human primates have what are called 'ischial tuberocities', which are hardened, leathery pads on their backside that allow them to sit down and use their hands without wearing a hole in their bum. Humans no longer need the ischial tuberocities because our enlarged glutes give us sufficient padding that we can sit on our bums for hours with no ill effects.

I don't think watching girls in thongs would have nearly the same appeal if humans had ischial tubercles instead of nice, round gluteal muscles.

Answer 2

That is a very good question my friend, and upon intense reflection and detailed examination into this situation I believe I have come up with a kick @ss answer. First off ... butt cracks do help humans seal-up the gross yet essential lower intestinal odors that may very well seep out otherwise. Secondly, the "crack" gives us all a more shapely and attractive sub-core look ... just imagine all of us with a visible hole (dang ugly), don't you think? Last off, but probably most important, the indispensible crack is a wonderful musical instrument ... you know what I mean. Just imagine all of the awkward moments you can create - in the elevator, on the bus, under the covers with your new girlfriend, during a boring lecture in class, in front of your boss at work, or even at Church! The butt crack is truely one of the greatest gifts God has bestowed on mankind, wouldn't you agree?

Answer 3

Okay. Why you're wondering about the evolution of butt cracks, I don't know;
What I do know is, the butt crack probably did come first, but people back then didn't really care about what people smelled like.
They had pretty much one track minds: kill, eat, reproduce.

and humans aren't the only animals with butt cracks, kid.
monkies have 'em to, I belive.

Answer 4

Excellent question!

What do you think is the purpose of the butt?
It is mainly cushioning for sitting down.

To understand this we look at our closest relatives, i.e. apes and monkeys.

Within the apes, the gorilla which is the most terrestrial (i.e. lives on land more than on trees) has the largest butt.
Compare the orangutan, which is mostly arboreal (lives in trees) with that of a gorilla.

Gorilla butt
http://www.game-reserve.com/gallery/gorilla/images/gorilla_silver-back_da.jpg?

Orangutan butt
http://bali.co.kr/zoo/image7/%BF%C0%B6%FB%BF%EC%C5%C127Orangutan.jpg


The reason is when an animal is terrestrial it sits a lot, and sitting on a bony *** will just hurt. Some of the other animals, like baboon which is not an ape but a monkey, that lives on land and looks for food in the ground by sitting down in the hot African land has adapted what is called “ischial callosities”. These are like butt-bunions . . . in that it’s a callus formation that protects the butt.

Human ancestors would’ve developed butts (the big cushions anyway) when they became primarily terrestrial in the savanna.

Also I believe it balances the body when humans also became bipedal (walking on two legs), unlike the other primates I mentioned (who can only be bipedal for small amounts of time).

I don’t know much about the hygiene of early humans, with water being a scarcity in the areas they lived in, I’m sure they wiped their butts much like dogs do on stones or dry grass or something.




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In case it wasn't clear, yes, some animals do have big butts (and thus butt cracks, like the gorilla.

Answer 5

Orangutan Butt

Answer 6

okay, i shall answer the more important question you asked, you got up so early because , your body didnt need any more sleep, or you drank to much caffine and your not sleeping well because of this, now the less important queston , but cracks, we have to cheeks so has to only take up some of the seat so somone else can sit wit us, when we fall on are butts it dosnt hurt has much plus the falling causes air to be trapped underneath us, in a sende it is like have air shocks, the air rushes out very fast thus softning are desent to the surface

Answer 7

But Cracks

Answer 8

The current form of humanity has been artificially chosen by generation after generation of humans with apparent choice as to what they like to see. Mating between humans with certain traits will produce human with certain traits. This is evolution at it's finest. "If it wasn't for Attila the Hun, we'd never have a Jennifer Love Hewitt."

Answer 9

most mammals have butt cracks, but the humans' are the biggest

Answer 10

Wow, thankyou! Just what I was searching for. I looked for the answer on other websites but I couldn't find them.