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Science Idle

Why Men Don't Have Sensory Whiskers and Spiny Genitals 226

sciencehabit writes "Most male mammals wield a penis covered with spines made of keratin, the same material that forms fingernails, to sweep out competitors' sperm and irritate a female into ovulating. Even chimpanzees, our closest relatives, have penile spines. So why don't men? A new study suggests that this feature disappeared due to a chunk of DNA that went missing after our evolutionary divergence from chimps. The researchers have identified another DNA deletion that may have contributed to humans' bigger brains."
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Why Men Don't Have Sensory Whiskers and Spiny Genitals

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  • by Anonymous Coward on Thursday March 10, 2011 @01:34PM (#35445384)
    Because I'm good at irritating females, yet somehow it doesn't lead to their ovulating.
    • by Meski ( 774546 )
      I'm seeing a new model of condom coming out, real soon now.
  • Huh? (Score:5, Funny)

    by eln ( 21727 ) on Thursday March 10, 2011 @01:40PM (#35445462)
    What, you mean these spines on my penis aren't normal?

    I'd better go see a doctor.
    • by darjen ( 879890 )

      Maybe you're actually a chimpanzee.

    • Re:Huh? (Score:5, Funny)

      by ColdWetDog ( 752185 ) on Thursday March 10, 2011 @01:56PM (#35445652) Homepage

      I'd better go see a doctor.

      Or a veterinarian.

    • Re:Huh? (Score:5, Funny)

      by Kelbin ( 1787356 ) on Thursday March 10, 2011 @02:14PM (#35445862)

      What, you mean these spines on my penis aren't normal?

      I'd better go see a doctor.

      I think it means you should stop shagging hedgehogs.

      • Re:Huh? (Score:4, Funny)

        by eln ( 21727 ) on Thursday March 10, 2011 @02:43PM (#35446234)

        I think it means you should stop shagging hedgehogs.

        Never!

      • "Ah well, anyone can make a mistake"
        - a hedgehog, climbing off a hairbrush

    • Re:Huh? (Score:5, Interesting)

      by tloh ( 451585 ) on Thursday March 10, 2011 @04:10PM (#35447318)

      What, you mean these spines on my penis aren't normal?.

      Let's hope it stays that way. from the article:

      "The interesting question - which for some reason the scientists didn't want to answer - is whether we could use a gene therapy to replace that deleted regulatory DNA. Basically, we'd add an activation switch to the whisker/spine sequence, flip it to "full blast," and start growing new body parts."

      I for one, do not think man should have his hands in his genes fiddling with himself. But then again, this is slashdot afterall, so...............

      • I for one, do not think man should have his hands in his genes fiddling with himself. But then again, this is slashdot afterall, so.....

        But wouldn't a spiny penis help men to keep their hands out of their jeans?

        Ohhhh, genes you say. . .

  • by scubamage ( 727538 ) on Thursday March 10, 2011 @01:42PM (#35445482)
    ...because I refrain from sex with porcupines and hedgehogs. And I didn't even have to RTFA.
    • by tomhudson ( 43916 ) <barbara.hudson@ ... a - h u dson.com> on Thursday March 10, 2011 @01:49PM (#35445542) Journal

      ...because I refrain from sex with porcupines and hedgehogs. And I didn't even have to RTFA.

      You mean like these 2 Russians [mosnews.com]

      Anton, 32, and Yevgeny, 30, residents of St. Petersburg, were spending their vacation in the United States with a group of friends, Life.ru website reports.

      At some point in their journey, the two got hold of a booklet listing the weirdest US laws. Since they were in Florida, their attention was drawn to a Florida law prohibiting sex with porcupines.

      After a good deal of whiskey, the Russians felt curious about what might have prompted the law, and went in search of the animal.

      Within one hour, a porcupine was found, and Anton and Yevgeny were drunk and brave enough to take off their pants and approach it.

      The next morning, both were standing at the Cedars Sinai clinic in Los Angeles, where amazed doctors plucked porcupine needles from their penises.

      • Don't click on those URL shorteners!
      • by g0bshiTe ( 596213 ) on Thursday March 10, 2011 @02:11PM (#35445822)
        Why if they were in Florida were they taken to Cedars in CA?
        • Re: (Score:3, Insightful)

          by tomhudson ( 43916 )
          They were tourists, not residents of Florida. Tourists have been known to travel from place to place, and I guess after their little escapade, they were in a hurry to leave Florida, since if they had gone to a Florida hospital, they would have been arrested.

          It's in the paragraph immediately under the part I quoted:

          Had the two not fled from Florida quickly enough, they would have had to face the law they had breached.

          California *probably* doesn't have a law about sex with porcupines (Note to self - ask

          • Off-Topic, I know... but I have yet to find the entertainment value in the whole Charlie Sheen debacle. Why must people continue bringing it up?

        • In Soviet Russia, space-time bend you.

      • by jfengel ( 409917 )

        Damn, I hate those "dumb laws" lists. Usually, it starts with an innocuous law like "No having sex with animals". Then some genius says, "No animals? Does that include porcupines? Hey, everybody, Florida says you can't have sex with porcupines!" knowing that everybody else is dumb enough not to go looking for the actual law. Instead, they go with "Gosh, those Floridians are stupid. One of 'em must have tried to have sex with a porcupine, and their legislators tried to ban that, rather than writing a n

        • If you think that's bad, there was a debate a few decades ago that went on about the law prohibiting sex with dead people.

          One legislator pointed out that could be interpreted differently from the obvious intent - like "my [spouse] is dead in the sack", as opposed to deceased.

          So they wasted time debating the differences between "dead" and "deceased", instead of just rewording it ...

          Or like the municipal bylaw up here that tried to ban massage parlours, by defining "massage" as "the manipulation of another person's body" and making it a crime for "someone who is not licensed to practice massage." Really bad definition, since it would ban pretty much all physical contact, include those same stupid politicians shaking hands during elections, or doctors setting broken bones, or you wiping your kid's runny nose.

          • by Nethead ( 1563 )

            .. or putting cuffs on someone that manipulated another persons body.

        • by vux984 ( 928602 )

          Usually, it starts with an innocuous law like "No having sex with animals".

          Would this be the same florida that failed to pass anti-bestiality laws as recently as last year?

          2009 --- http://www.tampabay.com/news/politics/legislature/article982771.ece [tampabay.com]
          2010 --- http://www.tampabay.com/news/courts/criminal/why-the-state-legislature-failed-to-pass-a-law-banning-bestiality/1092905 [tampabay.com]

          I can't offhand find any statute that specifically addresses porcupines; but its possibly some local thing... or perhaps its completely f

      • I don't really believe that story.

        First of all, as far as I can tell, there is no law against having sex with porcupines in Florida. A Google search of Florida code shows no hits for the term "porcupine." A search for documents including both the terms "sex" and "animal" doesn't show that bestiality is illegal per se. It is, however, illegal to fuck a porcupine (or animal of any kind) with children present, as it falls under general lewdness laws.

        Of course, that doesn't mean that two drunk Russians would go

  • by g0bshiTe ( 596213 ) on Thursday March 10, 2011 @01:46PM (#35445508)
    The phrase "wield a penis" appears in it.
  • by Anonymous Coward on Thursday March 10, 2011 @01:47PM (#35445522)

    All the women had sex with the first freak born without them.

  • Occam's Razor (Score:5, Interesting)

    by argStyopa ( 232550 ) on Thursday March 10, 2011 @01:52PM (#35445570) Journal

    ...because women, generally, don't want them? They by & large run the reproductive sweepstakes, even back in the "me big strong caveman, me conk woman on head" days when "consent" was a little more broadly interpreted.

    And which came first, male lack of spines, or female concealed ovulation?

    When analyzing the genetic record, how can one 'sort out' the distinction between DNA changes that have happened due to mutation, compared to the changes induced by broad and consistent female choice?

    • When analyzing the genetic record, how can one 'sort out' the distinction between DNA changes that have happened due to mutation, compared to the changes induced by broad and consistent female choice?

      That seems pretty easy -- the existence of a lack of spines originated due to a mutation, and became dominant due to natural selection. That's pretty much always the case.

      As far as the exact natural selection pressures which led to it becoming dominant, that's harder to say and I have no idea. I would imagine (i.e. wild-ass guess) that whichever came first, lack of spines or concealed ovulation, they were both predated by stronger pair-bonding.

      • I would guess the selection had more to do with females being able to more easily breed with one mate and have another mate take care of her brood. Time and time again, that seems to provide for fairly strong selective bias.

        • But that's the functional purpose of the spines -- to scoop out another male's semen so as to help ensure it is they who are impregnating the female. A male without them would be more likely to be the guy stuck raising someone else's kids.

          It seems like this would have only been advantageous after the development of mostly-monogamous pair bonding. Or after the development of concealed ovulation, so there'd be no obvious sign of fertility and thus copulations with multiple partners would, at least in half-a

    • Re:Occam's Razor (Score:5, Insightful)

      by joocemann ( 1273720 ) on Thursday March 10, 2011 @02:23PM (#35445994)

      The female chooses the mutant. The two things are not separate. The mutant male had no spines, so she chose him. Her sons had no spines, so other fems chose them. Fitness at work.

      • Or possibly the link they proclaim between the larger brain and lack of penile spines indicates that the "spineless" male figured out how to get more mates.
      • Or since we're monogamous... somewhat and men defended their mates they were no longer selected for and was just a weak gene.

        The point of the spines assumes that the females are mating with multiple males within a very short time period. Sociologically speaking that isn't thought to be common in human civilization.

        Instead of multiple matings, we just club the other guy before he gets around to any funny business.

        I would be curious if other mammals with similar social structures where males are prevented f

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      That's all fine and dandy, but considering that presumably, females of other species don't want them, either, why do they still exist there?

      • Re:Occam's Razor (Score:4, Insightful)

        by mdielmann ( 514750 ) on Thursday March 10, 2011 @03:38PM (#35446986) Homepage Journal

        That's all fine and dandy, but considering that presumably, females of other species don't want them, either, why do they still exist there?

        That's something of a presumption, given the fact that condoms can still be bought "ribbed for her pleasure".

        • by jamesh ( 87723 )

          That's all fine and dandy, but considering that presumably, females of other species don't want them, either, why do they still exist there?

          That's something of a presumption, given the fact that condoms can still be bought "ribbed for her pleasure".

          I think you'll find that 'spined for her irritation" condoms are somewhat more of a specialty item though, and probably not in particularly high demand.

    • because women, generally, don't want them?

      Keeping in mind that what the scientists are calling 'spines' in the article would be called 'bumps' by any normal people, and keeping in mind the relative lack of sensory nerves within the vagina - why would the female have any reason to choose the spineless mutant over the spined non-mutant? What would cause the proto-human female to make that choice while the proto-chimpanzee (and many other proto-species) made the opposite choice? (Since the genes are linked,

    • ...because women, generally, don't want them?

      Therefore men don't get to have them. Seems to be pretty standard for most guys I know.

  • by PolygamousRanchKid ( 1290638 ) on Thursday March 10, 2011 @01:53PM (#35445594)

    Most male mammals wield a penis covered with spines made of keratin, the same material that forms fingernails, to sweep out competitors' sperm and irritate a female into ovulating.

    Human females are different. They get irritated when ovulating. Before, during and after, in fact.

    • Re: (Score:2, Insightful)

      by Antisyzygy ( 1495469 )
      So they are always irritated?
      • by Pieroxy ( 222434 )

        Human females are different. They get irritated when ovulating. Before, during and after, in fact.

        So they are always irritated?

        Wow. You are sharp.

    • Pms happens about a week before ovulation. Menses are not ovulation. Glad to teach you.

      • by jamesh ( 87723 )

        Pms happens about a week before ovulation. Menses are not ovulation. Glad to teach you.

        Not married are you? PMS happens about a week before menstruation. Ovulation comes a bit after that is finished. PMS is likely related to the drop off in the various hormones at the end of the cycle that triggers the flushing of the uterine lining.

        One theory for the evolutionary cause is that by making the woman grumpy when she didn't get pregnant, she's more likely to split with her current partner and find one that is capable of doing the job. I'm not sure if I agree with that though... anyone who's ever

  • From TFA: Men don't have spiny penises or sensory whiskers on their faces because some DNA got deleted. Likewise some brain growth. Couple of researchers decided to look at what humans are missing relative to chimps, as opposed to what we have that is extra. They found a buncha stuff but don't really know what it means.

    Except that one area involves penile spines and sensory whiskers. Another area has to do with brain growth.

    Not a lot of actual info here.

    • As a dude with a beard I can tell you that I sort of pick up doors opening (wind and pressure change causes the whiskers to move) and bugs near my face with my whiskers.
      • I want to congratulate you on being the only person (so far) to comment on the "sensory whiskers" part of the story, and furthermore doing so without mentioning penises.
        • I certainly didn't want to read the post where he mentions both his beard and penises.

        • by blair1q ( 305137 )

          As a bicycle rider let me assure you, both penile spines and extra-sensitive follicles would have a deleterious effect on the sport.

    • That was my thought when I saw the article earlier. I'm not sure on what basis they concluded that there's a relationship between the two beyond happening in the same large block of time. DNA itself doesn't have to be a specific number of base pairs, but whatever additions or deletions happen can't screw too much with the mechanics or reproduction.

  • Wonder if the furry fanciers would be so eager if they knew it came as a matching set...
  • by Dunbal ( 464142 ) *
    Because human females collectively didn't like it for whatever reason, and selected against it. Nothing more, nothing less. Evolution in action.
    • by PPH ( 736903 )
      The next thing you know, they'll object to guys leaving their laundry lying around and breed that out of the species as well.
  • Spined for her pleasure?
  • by deimios666 ( 1040904 ) on Thursday March 10, 2011 @03:17PM (#35446750)

    Still in the genepool only very diluted: https://secure.wikimedia.org/wikipedia/en/wiki/Hirsuties_coronae_glandis [wikimedia.org]

    • Re: (Score:3, Funny)

      The home remedies in this previous version [wikimedia.org] are worth the read.
  • by gestalt_n_pepper ( 991155 ) on Thursday March 10, 2011 @03:24PM (#35446814)

    Which will no doubt take some barbed comments and pointed insights to thrust ourselves into a much deeper and greater understanding.

    Perhaps twice, after a 30 minute resting period.

  • by smellsofbikes ( 890263 ) on Thursday March 10, 2011 @03:50PM (#35447132) Journal

    First off, human males *do* have a mechanism to sweep out sperm from other males, consisting of the most visually obvious part of the male penis and protracted mechanical movement. We lost spikes, we evolved something else to do the same function. Secondly, there are many other mammals that have different methods for accomplishing the same thing: male squirrels have something like superglue that forms a plug after coitus, to prevent other males gaining access afterwards. (And female squirrels have claws and quite a bit of expertise in removing those same plugs, as you'd expect in any good arms race.) Likewise, many male lizards and insects avoid the problem by just staying connected until the female is ready to lay her eggs, which puts a whole lot of stress on the female during that period: they both get eaten pretty often.

    But if you really want to get weird, go look at insects like bedbugs, where males practice traumatic insemination: they don't go looking for an orifice, they make one, and let the female's body figure out what to do with the results. Or bees, where the barbs aren't there to stimulate ovulation but to make sure the penis breaks off and acts as a plug that can't be removed.

    And the next step weirder is hermaphrodites, where mating is a contest in which both wish to inseminate the other without getting inseminated, so mating strategies get seriously complicated. (The phrase 'penis fencing' has been used.)

    Anyone who is curious about this should read the brilliant book Promiscuity: the evolutionary history of sperm competition [amazon.com] by Tim Birkhead. It will make you relieved to be human.

  • We'll be puzzling over our lack of elbow talons.

  • by rtb61 ( 674572 ) on Friday March 11, 2011 @01:19AM (#35450382) Homepage

    A logical evolutionary step, where physical capability took second place to mental flexibility. Those groups of human where physical capability took precedence over mental flexibility died out when adverse environmental conditions left them less capable of surviving then the mentally flexible brethren who could throw rocks, start a fire and put on and take off a fur coat.

    The biggest driver for human evolution has likely been the recent (in evolutionary terms 2 million odd years) repeated ice ages giving precedence to mental agility of physical capability (being able to remain in a region and not having to pursue suitable climatic regions whilst stressed and against competition).

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