# What's the term for evolutionary side effects? **URL:** \ **Category:** Factual Questions\ **Created:** [August 9, 2010, 10:01pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758 "2010-08-09T22:01:49Z")\ **Posts on this page:** 14\ **Page:** 2
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 10, 2010, 6:54pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/21 "2010-08-10T18:54:18Z")
> [@qpw3141](#): > > Congratulations! > > You have just failed the [**Turing test**](http://en.wikipedia.org/wiki/Turing_test). šŸ˜ƒ [Moderator Note] Letā€™s avoid insults like this in General Questions. No warning issued, but donā€™t do this again. Colibri General Questions Moderator ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 10, 2010, 7:04pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/22 "2010-08-10T19:04:46Z")
> [@qpw3141](#): > > Would I be correct in thinking that the objection to what I said was because you/Colibri thought that I was suggesting that the crack appeared - was tunneled out of - something else? > > If thatā€™s the case I can well see why it was deemed senseless. That wasnā€™t what I was intending to say, though. When I said ā€˜necessity to provide a pathā€™ I intended that to imply: ā€˜necessity not to block the pathā€™. No, I didnā€™t think you meant that it was tunneled out. However, the way you stated it implied that the crack itself was a path for the passage of waste, not that it allowed spreading of the butt-cheeks for easier defecation. That was what I was calling nonsense. > [@qpw3141](#): > > As anyone who has actually defecated is well aware, the crack allows the buttocks to separate so that they do not get smeared with waste solids. The crack is probably the simplest evolutionary path that allowed the buttocks separate whilst we squatted thus aiding basic hygiene. Had we not needed that separation we would almost certainly have evolved a simpler shape for that area. However, you are falling in to the adaptionist mode of explaining it by recourse to a single adaptive explanation. The crack actually allows greater mobility for all kinds of movements of the leg, including movements to the side, not just for squatting. So explaining it just as an adaptation for ease of defecation is unnecessary. The crack may be necessary for the buttocks to work in locomotion in general. The main point about the butt-crack being a spandrel is not that it has no utility or purpose at all, but that it is a consequence of the hypertrophy of the buttock muscles themselves, not something that evolved for independent adaptive reasons. ---
**Author:** ![qpw3141](https://avatars.discourse-cdn.com/v4/letter/q/6bbea6/32.png) [@qpw3141](https://boards.straightdope.com/u/qpw3141)\ **Post date:** [August 10, 2010, 7:23pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/23 "2010-08-10T19:23:32Z")
> [@Colibri](#): > > > [@qpw3141](#): > > > > Would I be correct in thinking that the objection to what I said was because you/Colibri thought that I was suggesting that the crack appeared - was tunneled out of - something else? > > > > If thatā€™s the case I can well see why it was deemed senseless. That wasnā€™t what I was intending to say, though. When I said ā€˜necessity to provide a pathā€™ I intended that to imply: ā€˜necessity not to block the pathā€™. > > No, I didnā€™t think you meant that it was tunneled out. However, the way you stated it implied that the crack itself was a path for the passage of waste, not that it allowed spreading of the butt-cheeks for easier defecation. That was what I was calling nonsense. OK, I agree that would have been nonsense. I sometimes assume that whatā€™s obvious to me - that it was to facilitate the muscle groups parting - is obvious to everyone else - sorry. > [@](#): > > However, you are falling in to the adaptionist mode of explaining it by recourse to a single adaptive explanation. The crack actually allows greater mobility for all kinds of movements of the leg, including movements to the side, not just for running. So explaining it just as an adaptation for ease of defecation is unnecessary. The crack may be necessary for the buttocks to work in locomotion in general. It may well be there for locomotion in general. It, or something similar **must** exist as the anus cannot be covered over. If the anus wasnā€™t there I think it could be pretty well guaranteed that that area of our bodies would not be configured the way it is. Your original explanation referred solely to an almost accidental evolution into that configuration (as opposed to, for example, two hillocks with a gentle valley or more closely joined lumps of muscle, perhaps forming a smooth hemisphere) and it was that with which I was disagreeing. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [August 10, 2010, 7:36pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/24 "2010-08-10T19:36:03Z")
Plenty of animals have butt cracks. They are just covered up or filled in by a tail. The combination of no tail and bipedalism make the butt crack more apparent in humans. It is simply evidence that body form is established by constraints, not a genetically encoded picture. Also, as usual, sexual selection plays a role. I doubt menā€™s eyes auto-focus on a young womanā€™s butt crack by accident. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 10, 2010, 7:36pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/25 "2010-08-10T19:36:06Z")
> [@qpw3141](#): > > Your original explanation referred solely to an almost accidental evolution into that configuration (as opposed to, for example, two hillocks with a gentle valley or more closely joined lumps of muscle, perhaps forming a smooth hemisphere) and it was that with which I was disagreeing. Thatā€™s not really what I said. I said: [QUOTE=Colibri] the actual adaptive feature is the buttocks, which developed to hold the torso erect when we became bipedal. The butt-crack is just a non-adaptive consequence of this. [/QUOTE] Perhaps I shouldnā€™t have used the word ā€œnon-adaptive.ā€ The butt-crack may have an adaptive reason in that it allows for greater mobility of the buttocks, whether for locomotion or for defecation; however, the actual adaptation is the buttocks. The butt-crack is not adaptive in and of itself, but only with respect to the buttocks. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 10, 2010, 7:40pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/26 "2010-08-10T19:40:38Z")
> [@TriPolar](#): > > Plenty of animals have butt cracks. They are just covered up or filled in by a tail. The combination of no tail and bipedalism make the butt crack more apparent in humans. It is simply evidence that body form is established by constraints, not a genetically encoded picture. True. See [here.](http://stevegarufi.com/clydesdales3.jpg) ---
**Author:** ![Shot\_From\_Guns](https://avatars.discourse-cdn.com/v4/letter/s/ccd318/32.png) [@Shot\_From\_Guns](https://boards.straightdope.com/u/Shot_From_Guns)\ **Post date:** [August 10, 2010, 9:16pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/27 "2010-08-10T21:16:39Z")
I donā€™t want to know what you plugged in to GIS (or what results you had to wade through) to get that return, **Colibri**. ---
**Author:** ![Cheshire\_Human](https://avatars.discourse-cdn.com/v4/letter/c/5f8ce5/32.png) [@Cheshire\_Human](https://boards.straightdope.com/u/Cheshire_Human)\ **Post date:** [August 10, 2010, 10:29pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/28 "2010-08-10T22:29:31Z")
> [@Shot\_From\_Guns](#): > > I donā€™t want to know what you plugged in to GIS (or what results you had to wade through) to get that return, **Colibri**. ā€œHorseā€™s assā€ šŸ˜ƒ ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [August 10, 2010, 11:19pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/29 "2010-08-10T23:19:09Z")
> [@CC](#): > > A sense of humor is one that I think was referred to that way. Language ability clearly has significant benefits regarding the passing of genes along. The assertion was that a sense of humor, an inadvertent adjunct of our ability to use language, while a lovely feature of individuals, doesnā€™t in and of itself provide evolutionary advantage. While one might argue that point, the example stands as one that illustrates what Iā€™m referring to - a side-effect of some adaptation. \ Humour may be a side effect, but itā€™s debatable whether it confers an evolutionary advantage. Humour in modern society is supremely important. People want to have friends who are funny. Women want to date guys with GSOH. Any social gathering devoid of humour is seen as a disaster. My own theory is that humour is a way of demonstrating intelligence. But not intelligence in a book smarts way, which wouldnā€™t have been so useful to our remote ancestors. Instead it demonstrates skills of pattern recognition / association and other mental skills, which may be useful in more serious contexts. For most of our recent evolutionary history, the main selection force on our genes has been the opinions and actions of other human beings. I think humour has evolved as part of this process, along with other abstract mental skills and sex-selected physical characteristics. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 11, 2010, 1:18am UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/30 "2010-08-11T01:18:34Z")
> [@Cheshire\_Human](#): > > > [@Shot\_From\_Guns](#): > > > > I donā€™t want to know what you plugged in to GIS (or what results you had to wade through) to get that return, **Colibri**. > > ā€œHorseā€™s assā€ šŸ˜ƒ Exactly right. šŸ˜ƒ ---
**Author:** ![qpw3141](https://avatars.discourse-cdn.com/v4/letter/q/6bbea6/32.png) [@qpw3141](https://boards.straightdope.com/u/qpw3141)\ **Post date:** [August 11, 2010, 7:41am UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/31 "2010-08-11T07:41:53Z")
> [@Colibri](#): > > > [@qpw3141](#): > > > > Congratulations! > > > > You have just failed the [**Turing test**](http://en.wikipedia.org/wiki/Turing_test). šŸ˜ƒ > > [Moderator Note] > > Letā€™s avoid insults like this in General Questions. No warning issued, but donā€™t do this again. > > Colibri > General Questions Moderator That was supposed to be a joke - more about the possibility of the Turing test throwing up whimsical errors, certainly not an insult. Oh, well. ā˜¹ ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [August 11, 2010, 3:05pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/32 "2010-08-11T15:05:05Z")
I just wanted to say Iā€™ve never encountered such a serious and pedantic conversation that involved butt cracks and pictures of horseā€™s asses. Congratulations, all of you. Thirty posts in, and barely any jokes. _sniff_ Iā€™m so proud! ---
**Author:** ![Shot\_From\_Guns](https://avatars.discourse-cdn.com/v4/letter/s/ccd318/32.png) [@Shot\_From\_Guns](https://boards.straightdope.com/u/Shot_From_Guns)\ **Post date:** [August 11, 2010, 3:16pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/33 "2010-08-11T15:16:13Z")
> [@Colibri](#): > > > [@Cheshire\_Human](#): > > > > ā€œHorseā€™s assā€ šŸ˜ƒ > > Exactly right. šŸ˜ƒ Impossible. I happen to know Iā€™m at \*least \*the first fifty returns for that search string. > [@purplehorseshoe](#): > > Thirty posts in, and barely any jokes. _sniff_ Iā€™m so proud! Might not want to inhale through your nose like that in here. ---
**Author:** ![Cheshire\_Human](https://avatars.discourse-cdn.com/v4/letter/c/5f8ce5/32.png) [@Cheshire\_Human](https://boards.straightdope.com/u/Cheshire_Human)\ **Post date:** [August 11, 2010, 3:36pm UTC](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758/34 "2010-08-11T15:36:16Z")
> [@Shot\_From\_Guns](#): > > Impossible. I happen to know Iā€™m at \*least \*the first fifty returns for that search string. So, You are ā€œthe horse of a different colorā€ from the Wizard of Oz? I saw lots of different colored horseā€™s asses on the first page, and I didnā€™t even look at the second. Your page rank is slipping, call your search engine optimization people. They arenā€™t doing their jobs. šŸ˜ƒ [Previous page](https://boards.straightdope.com/t/whats-the-term-for-evolutionary-side-effects/549758.md?page=1)