Penis Size Matters More to Men’s Attractiveness Than Previously Thought

By Gemma Tarlach | April 8, 2013 2:02 pm

Figures representing the most extreme height, shoulder-to-hip ratio, and penis size are on the right and left; the center figure displays the average values. Image courtesy Brian Mautz & MakeHuman software

Sorry, fellas: Size does matter, according to science.

The size of a human penis is more closely correlated to sexual attractiveness than previous studies indicated, according to findings published online today in Proceedings of the National Academy of Sciences. The new research, which took into account other traits associated with attractiveness, also suggests that female preferences about penis size may have influenced how human male genitalia evolved.

The subjects of the study were 103 heterosexual Australian women. The researchers presented the subjects with projected images of life-size, computer-generated male figures that rotated 30 degrees to each side for easier evaluation. Previous research used two-dimensional drawings of male figures, each varying only in penis length. By contrast, the three-dimensional figures used in the new study varied in height and shoulder-to-hip ratio as well as flaccid penis size. Each of the three traits tested had seven possible values; the study included videos for all 343 possible trait combinations.

Researchers modeled additional traits in the study to assess whether the three aspects—height, shoulder-to-hip ratio and penis length—interacted to influence overall attractiveness. Their findings revealed that female participants showed strong preferences overall for taller men, men with greater shoulder-to-hip ratios—a “T” shape typically associated with masculine physiques—and longer penis length.

Although previous research indicated strong female preference for taller men and those with greater shoulder-to-hip ratios, the study is significant for demonstrating that penis length is as important as height and more important than shoulder-to-hip ratio in influencing attractiveness. The findings contradict previous studies that reported penis size was unimportant to most females.

Female participants in the new study who viewed random subsets of the life-size figures were also quick to rate those they found unattractive, but spent significantly longer gazing at the computer models they found appealing, particularly those with longer penises. This pattern is consistent with a human tendency to view attractive things for a longer time than those perceived as unattractive.

Controlling for shoulder-to-hip ratio, the study also revealed that larger penis size had a greater influence on whether a taller man was judged attractive. Researchers suggested the result could be due to perceived penis size relative to height or because “general discrimination against short men” is such that “even a larger penis did little to increase their net attractiveness.”

The study also pointed out, however, that women’s penile preferences aren’t always realistic. While the average flaccid penis length among men is 3.5 inches, the maximum length in the study was 5.1 inches, and the response trend indicated that women would have preferred an even larger penis.

Although some previous research has suggested female preferences about the male form can change based on hormone levels, the study found no effect of either contraception use or phase of menstrual cycle on which figures participants considered attractive.

According to the researchers, the basis for a female preference for a larger penis in her mate is not known, but may be related to cultural influences or her previous sexual experience. Regardless of why the preference exists, it may have influenced the evolution of penis size in humans. Before the advent of clothing, due to humans’ upright posture and the male’s “protruding, nonretractable genitalia,” as the study describes it, the penis was readily seen even when flaccid, and females were able to make precopulatory mate choices based on its size. This may have led to males with larger penises having more opportunities to mate and pass on the trait to their offspring.

CATEGORIZED UNDER: Health & Medicine, top posts
MORE ABOUT: sexual selection
  • Adrian J. Ebsary

    Broken link on the word ‘findings’.

    • Lisa Raffensperger

      Fixed now, Adrian.

  • John A. Anderson

    How are women supposed to gauge penis size, since most men wear trousers?

    • Shaun Herndon

      Something called a “bulge” in the pants is visible to females.
      Also see height & shoulder to waist ratio in the article

  • JonFrum

    Note to self: ixnay on the emigration to Australia.

    But seriously folks… 103 Australian women looking at pictures tells us about evolution that went on tens or hundreds of thousands of years ago? Stop and think.

  • hudasx

    Another study generalizing human nature based on a few white people.

    • Buddy199

      Where does it say the participants were all white?

      • Kevin S.

        Though it doesn’t say all the participants were white, but Australia is 80% white, with most of the rest being Asian, so the sample was probably skewed toward white people (particularly of Northern European ancestry) than the world as a whole.

        And there are problems outside of race in this study. It suffers from WEIRD (Western, Educated, Industrialized, Rich, and Democratic) syndrome. Australia is definitely a WEIRD country, so we can’t even tell if these results reflect a timeless trend in all human cultures or a trend in modern Western culture.

        • Buddy199

          Western, Educated, Industrialized, Rich and Democratic

          How awful. As opposed to 3rd World, Illiterate, Feudal, Impoverished and Authoritarian.

          Odd how if given the choice, the vast majority of the latter choose the former.

          • Kevin S.

            This discussion isn’t about your opinion of various groups of people. It’s about getting representative samples of humanity before you make sweeping statements about human nature. Because much of the world isn’t WEIRD, you can’t assume that what holds true for WEIRD people applies to everybody, everywhere.

          • Buddy199

            “WEIRD” – Laughable, I guess that’s the new multicultural meme in community college poli-sci these days. The usual Western liberal cultural guilt and self-loathing masquerading as ideological piety. The modern equivalent of the medieval hair shirt and self-flagellation.

          • hudasx

            I didn’t say they were all white. Fifty of the 106 subjects were Anglo/Celtic, 13 were North/Western European. And less than 10 of everyone else. None of them were African American. Presumably they were all from the US. Yes, that sounds like a representative sample of representative samples in psychological studies. The only reason this study was notable was that the results differed from previous other studies.

          • Kevin S.

            I wouldn’t know about community college poli-sci, since I haven’t taken a poli-sci class in 20 years. I first found out about the acronym from Jared Diamond’s new book.

          • dogctor

            Agreed. They need to repeat the study internationally and then compare penis sizes to IQs

            Why isn’t this article in NCBI ROFLMAO?

    • TRACYj.•*¨`*•.¸.•*


  • BettyGeneric

    Seriously. This was a serious study conducted by scientists.

  • Luke Pettit

    I was under the impression (from Masters and Johnson)? that flaccid penis size was not a true indicator of erect penis size. Some flaccid penises while seeming large get no larger when erect, where as some smaller penises get 5x larger from their flaccid state. Surely this type of study has been done in the past by Masters and Johnson. Did anyone bother to check their research?
    “Grower, not a shower”

    Sorry world don’t judge us by some 103 B P’s lol
    I’m happy with mine if it’s not big enough for you then maybe a concrete bollard my be a better choice of partner. 😀

    • Xiudo

      If anything this proves the point more. The attractiveness of the male is based upon the non functional looks. the Shower is more initially attractive than the grower.

  • William Mayes

    Since the only purpose of a man is to please women, I expect that by natural selection, in a million years or less, men will need a wheel-barrow to carry their penises with.

    • Ben Hálame-Lamí

      Thanks for making my night ! :)

  • Buddy199

    Interesting, most of these findings also appear to apply to wallet size.

    • Linda McLaren

      I don’t see anywhere that these test figures could carry a wallet.

  • Chris

    One size fits all

  • Scott

    This study is flawed because it opposes penis length against only shoulder-to-hip ratio and height. It leaves out other features of physical attractiveness in the face, features of attractiveness in the clothed man like good fashion and hygiene, and a thousand other factors like humor and intelligence that would be impossible to study.

    Pitted against just two other variables, of course the women are going to zero in on the penis. Especially since the researchers have lit these 3D figures so that the shadow on the big penis stretches half way down the guys leg and the little penis’s shadow is barely visible! In no way is this a valid study.

  • Devon Scott

    These comments are mind bogglingly dismissive. I suppose because it has to do with penis size the discourse demonstrates less about science and more about a notable episode of South Park. I’d suppose that until you have a budget and means to create some idealized world representative sample you should never run tests, or publish and share them. Maybe a more productive comment would be “Interesting, but I wonder if that test would run the same across Australian Aboriginal cultures.” or “This isn’t worth repeating without more diversified sets of subjects and features.” Rather than made up anthropology jargon or subjective cultural jabs at sitcom male/female dichotomies. I have a sinus headache and shouldn’t be allowed to comment on anything today; please enjoy these articles.

  • Alan

    Fascinating! Another example of how properly conducted empirical data contradicts conventional wisdom. I wonder if a similar study might dispel the notion that men are attracted to larger breasts? Have men’s penises actually evolved larger? Have women’s breasts?

  • Alan

    Also wondering, is there any truth to the conventional wisdom that a man’s penis size has any relation to other physical attributes (which a woman can see) such as height, hand size, etc.
    Also, since human language was first invented, females have been discussing the local men’s respective penis size and how good they are in bed with each other, so no mystery about how women might know once men started covering up.

  • SIR Fancypants

    It’s funny that once men are put on the pedestal to be examined, prodded, and judged – we’re so quick to scream “inaccurate representation, bad data, skewed (this/that)”… Hahaha! Now you know how women must have felt over at least eighty years of being poked, prodded, and inaccurately represented in movies, pictures, and television. Because if a woman is ugly, well, she can just find a rock to hide under. If a man is found to be “ugly” – THIS MEANS WAR!!!

  • Văn Minh Nguyễn

    I have a large penis, and I’ve never met a woman who found me attractive :-(
    There are way more than one measure to account for a woman’s perspection of attractiveness (the same works vice versa).

  • Holly Stinson Smith

    If the conclusion to this study is true, then sure the opposite would be true as well: women would have evolved to have larger and larger breasts (because men clearly have a preference for larger breasts.) Despite that “preference” there is still enormous variety among breast size & shape in women around the world. While it may alter how much ogling they get as young women, it doesn’t seem to have an effect on whether they marry, have children, or breastfeed. I suspect the same may be true here. Just because women may deem something attractive, doesn’t ultimately decide whether they will choose the person with that physical trait. There are more important variables: such as personality, availability, economic status, compatible values.

  • Patrick Thompson

    Doesn’t, as far as I’m reading here, factor in personality. Which along with physique is basically all the female knows at first since the time we started wearing concealing clothes. Something, I’m speculating, which could influence attractiveness of not only penis size but other physical features. I wonder what the difference in attractiveness would be between one night stands and more typical sexual relations.

  • Chris

    No surprise here, women are attracted to well built taller guys with a large penis. I admit I’m attracted to tall blond women with the classic 36/24/36 in a d cup! So what? I just feel bad for the guys who go out and get enlargement surgery because the feel inadequate. Almost every woman I know says bigger is better, whatever size that is who the hell knows!

  • jovenal

    Mh. How much resources have been spent to find this obviousness?

  • Christel Platt

    lmao, ya think?!

  • Psychologgg

    Weak study, sexual selection is far more complex,

  • disqus_brwFvDA3vq

    I thought that penis size was determined mostly by hormone exposure in utero, and not by any genetic factor?

  • sternhead

    Can a business have a penis?


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