What causes gender differences in responses to farting? Background: By casual observation, I have noticed that males tend to react differently to the sound of a fart. It seems that men are more likely to laugh whereas women are more likely to show signs of disgust.
I thought that perhaps there might be some evolutionary basis for this.

Questions


Is there any serious psychological research on the causes of our responses to farting?
Are there any systematic gender differences?
What are the posited causes of such gender differences?
I was shocked at how difficult it was to find systematic scientific research on the psychology of flatulence. The main empirical paper appears to be one by Lippman (1980). It seems to be hard to get a copy of the original. However, the author of the Neurotic Physiology blog discusses the paper at length. 

Lippman study

Lippman asked participants to rank various hypothetical farters based on various factors. With regards to sex differences the blogger writes:


  The sex differences were a little surprising. It turns out that women
  are more forgiving of loud, accidental farts (girls, we've all been
  there I'm sure), and don't ding the farter so much on "politeness"


However, when you think about the problem there are different kinds of sex differences in fart ratings: Men rating male farters; men rating female farters; women rating male farters; and women rating female farters.  This question really only addresses how women rate others in general. 

Toilet psychology

Recently, a book was released by Professor Nick Haslam called "Psychology in the Bathroom". There's a good summary in The Psychologist (2012, PDF). 
The book specifically aims to redress the lack of psychological research devoted to excretion and related matters.

One particular passage from the book summary in The Psychologist may provide a potential explanation for gender differences in perceptions of farting:


  A common thread running through these differences is that women’s
  excretion is more hidden, emotionally fraught and suppressed than
  men’s. The incompatibility of femininity and excretion is nicely
  expressed in Jonathan Swift’s poem ‘The lady’s dressing room’, in
  which a suitor sneaks into his beloved’s room only to  find evidence
  of her dirty corporeality, including sweaty garments, beslimed towels
  and encrusted combs. Upon discovering her chamber-pot he slinks away
  in horror, lamenting ‘Oh! Celia, Celia, Celia shits!’ The same
  sentiment is expressed less poetically by an American undergraduate:
  ‘women are supposed to  be non-poopers’ (Weinberg &amp; Williams, 2005,
  p.327). Despite our enlightened modern attitudes to gender equality,
  women are still judged more severely for violations of this ideal of
  untaintedness than men.  In one study (Goldenberg &amp; Roberts, 2004), a
  female experimenter who excused herself to use the bathroom was
  evaluated more negatively than one who excused herself to get some
  paperwork: no such difference was found for a male experimenter.


General thoughts

So in summary, research on farting has generally been neglected by the psychological literature.

There is some evidence to suggest that women who fart are judged more negatively than men who fart. However, presumably this would vary a lot with context, who is farting, and who is recognising the farting. 
It would also presumably be a cultural phenomena.

One theory to explain gender differences is that a lack of purity is often associated with activities related to excreting, such as farting. Farting loudly or openly may symbolise a lack of control over excretion or remind others that a person is an excreting being. Purity is sometimes  associated with a feminine ideal. Thus, farting may be socially more detrimental for a female than a male. Anyway, the preceding statements are largely based on theory; I'd like to see a lot more empirical evidence before I take them too seriously.

References


Lippman, LG. "Toward a social psychology of flatulence: The interpersonal regulation of natural gas". Psychology: a Quarterly Journal of Human Behavior, 1980.
Goldenberg, J.L. &amp; Roberts, T. (2004). The beast within the beauty: An
existential perspective on the objectification and condemnation of women. In J. Greenberg, S.L. Koole &amp; T. Pyszczynski (Eds.) Handbook of experimental existential psychology (pp.71–85). New York: Guilford.
Haslam, N. (2012). Psychology in the Bathroom. Palgrave Macmillan.
Haslam, N. (2012), Toilet psychology. The Psychologist. 25, 6, 430-433. PDF