# The non-evolution of the human anus??? **URL:** \ **Category:** Factual Questions\ **Created:** [July 15, 2008, 9:48pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605 "2008-07-15T21:48:28Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![dfreeman87](https://avatars.discourse-cdn.com/v4/letter/d/d78d45/32.png) [@dfreeman87](https://boards.straightdope.com/u/dfreeman87)\ **Post date:** [July 15, 2008, 9:48pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/1 "2008-07-15T21:48:28Z")
There’s no real good way to ask this…so here it is: Why do I have to wipe my ass? I find it to be nothing short of a tragedy that humans have to wipe their ass to stay hygienic. Animals the world over seem to have developed a sound method to avoid this hassle. Take a dog for example, not that I spend my spare time examining Rover’s bowel movements, but when a dog goes to makes bears he simply flips out his anus/rectum, expels his pile, and then flips it back in. Presto, a clean butt hole. How did humans miss this evolutionary milestone? Having done a stint in the Marines, spending several days out in the field with no real good way to clean myself, my exit would often become chaffed an irritated. This was such an occurrence, and not just for me I might add, that a name was developed for the phenomenon…Baboon Ass. ---
**Author:** ![Freudian\_Slit](https://avatars.discourse-cdn.com/v4/letter/f/5daacb/32.png) [@Freudian\_Slit](https://boards.straightdope.com/u/Freudian_Slit)\ **Post date:** [July 15, 2008, 9:53pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/2 "2008-07-15T21:53:14Z")
Well, dogs and cats have to eventually lick their own assholes, right? So maybe we do have it better. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [July 15, 2008, 10:05pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/3 "2008-07-15T22:05:14Z")
It’s the modern human diet. It is not conducive to neatly formed, solid stools that pop out with nary a skid. Either go back to a hunter-gatherer diet, or cultivate an opiate habit. Just don’t overdo on the opiates or you’ll have to go excavating to get it out. Or find the right mix of fresh foods with adequate fiber content. Me, I favor a bidet. ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [July 15, 2008, 10:10pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/4 "2008-07-15T22:10:30Z")
[QUOTE=Freudian Slit] Well, dogs and cats have to eventually lick their own assholes, right? [/QUOTE] My dog plainly thinks of it not as “have to” but as “get to.” 😛 ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [July 15, 2008, 10:17pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/5 "2008-07-15T22:17:04Z")
And besides, human beings have hands. The jungles and savannahs have leaves. Human beings have the ability use those leaves to wipe their assholes. If your cat had the ability to wipe its ass with leaves rather than lick itself clean, I’m pretty sure it would choose the leaf route. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [July 15, 2008, 10:27pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/6 "2008-07-15T22:27:39Z")
[QUOTE=Lemur866] And besides, human beings have hands. The jungles and savannahs have leaves. Human beings have the ability use those leaves to wipe their assholes. If your cat had the ability to wipe its ass with leaves rather than lick itself clean, I’m pretty sure it would choose the leaf route. [/QUOTE] I don’t think I’d want to wipe my ass with any leaves growing on the savannah… 😉 ---
**Author:** ![ivan\_astikov](https://avatars.discourse-cdn.com/v4/letter/i/58f4c7/32.png) [@ivan\_astikov](https://boards.straightdope.com/u/ivan_astikov)\ **Post date:** [July 15, 2008, 10:35pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/7 "2008-07-15T22:35:17Z")
Excuse the unwholesome imagery, but after 40 years of wiping my own butt, why am I still freaked out when my finger goes through the tissue? Perhaps this thread should now be moved to GD? 😃 ---
**Author:** ![Yllaria](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yllaria/32/3452_2.png) [@Yllaria](https://boards.straightdope.com/u/Yllaria)\ **Post date:** [July 15, 2008, 10:36pm UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/8 "2008-07-15T22:36:35Z")
I hate to say this, but anyone who thinks that evolution owes them Clean has never seen a herd of cows. Or seen my dog drag her backside on my floor. ---
**Author:** ![dfreeman87](https://avatars.discourse-cdn.com/v4/letter/d/d78d45/32.png) [@dfreeman87](https://boards.straightdope.com/u/dfreeman87)\ **Post date:** [July 16, 2008, 12:07am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/9 "2008-07-16T00:07:42Z")
[QUOTE=Yllaria] I hate to say this, but anyone who thinks that evolution owes them Clean has never seen a herd of cows. Or seen my dog drag her backside on my floor. [/QUOTE] Your dog drags its butt because it has worms, not because it’s wiping. Back on to the subject, I used a dog as a simple example, but no other animal needs to wipe its butt to avoid baboon ass. Why us? Why can’t my rectum flip inside out and back again every time I make a bowel movement? ---
**Author:** ![Chez\_Guevara](https://avatars.discourse-cdn.com/v4/letter/c/aeb1de/32.png) [@Chez\_Guevara](https://boards.straightdope.com/u/Chez_Guevara)\ **Post date:** [July 16, 2008, 12:08am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/10 "2008-07-16T00:08:35Z")
[QUOTE=Lemur866] Human beings have the ability use those leaves to wipe their assholes. [/QUOTE] Comments like this do nothing to maintain confidence in the Toilet Paper sector. ---
**Author:** ![Freudian\_Slit](https://avatars.discourse-cdn.com/v4/letter/f/5daacb/32.png) [@Freudian\_Slit](https://boards.straightdope.com/u/Freudian_Slit)\ **Post date:** [July 16, 2008, 12:12am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/11 "2008-07-16T00:12:36Z")
[QUOTE=dfreeman87] Your dog drags its butt because it has worms, not because it’s wiping. [/QUOTE] I’ve seen non-wormy dogs dragging their ass across the floor. And I’ve seen dogs who needed help in the wiping department…why would it necessary be a worms thing, and not a dirty bottom thing? ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [July 16, 2008, 12:16am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/12 "2008-07-16T00:16:48Z")
[QUOTE=dfreeman87] I used a dog as a simple example, but no other animal needs to wipe its butt to avoid baboon ass. [/QUOTE] You clearly haven’t seen the south end of a sheep recently. :dubious: ---
**Author:** ![dfreeman87](https://avatars.discourse-cdn.com/v4/letter/d/d78d45/32.png) [@dfreeman87](https://boards.straightdope.com/u/dfreeman87)\ **Post date:** [July 16, 2008, 12:19am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/13 "2008-07-16T00:19:22Z")
[QUOTE=Colophon] You clearly haven’t seen the south end of a sheep recently. :dubious: [/QUOTE] When was the last time your Sheep needed hemorrhoid cream??? ---
**Author:** ![dfreeman87](https://avatars.discourse-cdn.com/v4/letter/d/d78d45/32.png) [@dfreeman87](https://boards.straightdope.com/u/dfreeman87)\ **Post date:** [July 16, 2008, 12:21am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/14 "2008-07-16T00:21:46Z")
[QUOTE=Freudian Slit] I’ve seen non-wormy dogs dragging their ass across the floor. And I’ve seen dogs who needed help in the wiping department…why would it necessary be a worms thing, and not a dirty bottom thing? [/QUOTE] That would only make sense if the butt dragging were routinely after pooing. I think they do i more for itching or fun. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [July 16, 2008, 12:24am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/15 "2008-07-16T00:24:56Z")
[QUOTE=dfreeman87] When was the last time your Sheep needed hemorrhoid cream??? [/QUOTE] Pile cream maybe not, but sheep tend to have their tails docked to reduce the incidence of “dags” (shit matted in the wool, to me and you) and fly strike (that’s flies laying eggs on the skin leading to maggot infestation). Sorry if you’re eating and reading, BTW. 😛 ---
**Author:** ![Yllaria](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yllaria/32/3452_2.png) [@Yllaria](https://boards.straightdope.com/u/Yllaria)\ **Post date:** [July 16, 2008, 12:29am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/16 "2008-07-16T00:29:58Z")
[QUOTE=dfreeman87] When was the last time your Sheep needed hemorrhoid cream??? [/QUOTE] When was the last time that you ended up with maggots in your anus because of a build-up of fecal matter in your wool? Or, like the cows, when was the last time that your back legs, tail, and rump were covered with drying runny stuff? I’ll admit that well-fed domestic dogs have it pretty good, though, in the elimination department. I’m guessing that it isn’t just evolution that’s driving that, though. There’s some unnatural selection going on there. ---
**Author:** ![dfreeman87](https://avatars.discourse-cdn.com/v4/letter/d/d78d45/32.png) [@dfreeman87](https://boards.straightdope.com/u/dfreeman87)\ **Post date:** [July 16, 2008, 12:33am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/17 "2008-07-16T00:33:18Z")
[QUOTE=Colophon] Pile cream maybe not, but sheep tend to have their tails docked to reduce the incidence of “dags” (shit matted in the wool, to me and you) and fly strike (that’s flies laying eggs on the skin leading to maggot infestation). Sorry if you’re eating and reading, BTW. 😛 [/QUOTE] Hilarious…but none the less, it still doesn’t explain why we require such care to avoid the nasties. The only plausible explanation that I can come with is that the need came about as a side effect of walking upright. Any comments??? ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [July 16, 2008, 12:36am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/18 "2008-07-16T00:36:15Z")
Thing is, there’s no real evolutionary pressure for a better design. It does the job, and we have hands that can reach to clean up. It might cause a bit of irritation, but nothing that will stop us from passing our genes (including those for baboon arse) along to the next generation. Something to bring up next time you meet a proponent of Intelligent Design, perhaps? ---
**Author:** ![clairobscur](https://avatars.discourse-cdn.com/v4/letter/c/839c29/32.png) [@clairobscur](https://boards.straightdope.com/u/clairobscur)\ **Post date:** [July 16, 2008, 12:58am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/19 "2008-07-16T00:58:58Z")
[QUOTE=dfreeman87] . Why us? Why can’t my rectum flip inside out and back again every time I make a bowel movement? [/QUOTE] For all I know, it could be doing just that, I never checked. But anyway, it wouldn’t help since contrarily to dogs, cats, etc.. we have over-sized buttocks. Which allows us to stand up and free our hands so that we can wipe our asses. 😉 ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [July 16, 2008, 12:59am UTC](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605/20 "2008-07-16T00:59:35Z")
[QUOTE=dfreeman87] Your dog drags its butt because it has worms, not because it’s wiping. [/QUOTE] That’s not always why either. Often it’s because of an issue with their anal glands. [Next page](https://boards.straightdope.com/t/the-non-evolution-of-the-human-anus/456605.md?page=2)