The female interest in spurring sperm competition or a desire to monopolize the attention and resources of multiple men

This headline sounds better than 'Women prefer gang bangs, while men group sex'. OK, stage is open for the paper:

Evolutionary approaches: Integrating pornography preferences, short-term mating, and infidelity

Abstract

There are a number of questions concerning human sexual psychology where pornography consumption may be particularly informative, yet evolutionary psychologists have been slow to incorporate it into research designs. This study examines the relationships between pornography preferences, individual's sex, proxies for short-term mating strategies (e.g., life history strategy, sociosexuality), and infidelity. For example, we predict that men, more than women, will be interested in group sex (i.e., threesomes and gangbang) scenarios in pornography as a result of selective pressures for sperm competition. Further, specific activities and sexual situations in pornography are likely to be differentially appealing based on the sexual strategies pursued by consumers. Thus, women who have higher, versus lower, intentions of committing infidelity will be more interested in activities like group sex, given the latter involves no commitment. Results suggest that men exhibit more interest in group sex scenarios than women, and intentions to commit infidelity are also associated with greater interest in group sex scenarios. Collectively, our findings demonstrate the usefulness of incorporating consumption of pornography measures in evolutionary social psychological research.

Turns out women like watching gangbangs, rough sex and bondage.

Data released by Pomhub show a wide variety of material being viewed as well as sex differences in search interests, with men viewing age (teen, MILF) and race related categories more, and women viewing videos from the categories gangbang, rough sex, and bondage more. It is this latter point, which sparked this research. Evolutionary perspectives on sexuality suggest that women should be less not more interested in gangbang pornography, given that they tend to either prefer long-term relationships involving trust and commitment or: when seeking short-term opportunities, place a premium on high levels of physical attractiveness. Gangbangs typically involve a context of numerous male partners and anatomy: do not involve monogamous committed relationships: and are not focused on male attractiveness in the way female attractiveness is highlighted. 

Thus: there is a gap between Pornhub's reports of greater female interest in gangbang porn and theoretical assumptions about sexual psychology. This study examines the relationships between pornography preferences: individual's sex: proxies for short-term mating strategies (e.g.: life history strategy: sociosexuality), and infidelity 

Men orgasm more in group sex.

Men were more interested in group sex scenarios in porn such as gangbangs and threesomes, as has been noted in previous studies of sex differences in sexual fantasies. This finding contradicts the search results published by PornHub. Interestingly, Burch et al found that men were more likely to engage in group sex than women, enjoyed group sex more, reported greater sexual satisfaction: and had greater ease of achieving orgasm. 

While women discover more difficulties in that discipline.

In contrast, women reported more fleeting orgasms, more difficulty achieving orgasm in group sex contexts: and significantly less sexual satisfaction. Male sexual behavior in this context may be driven by both sperm competition and the Coolidge effect, and this distraction is detrimental to female sexual satisfaction. Given these ‘real life’ data: it may not be surprising that women do not seek out fantasy group sex scenarios as captured by pornography. 

Women are more into gangbangs, or more gentlemanly put "the attention and resources of multiple men".

The most preferred threesome pornography for men was one male two females, which may reflect male preferences for sexual novelty and multiple female partners. Female interest in threesomes was greater for one female two males. This could reflect female interest in spurring sperm competition or a desire to monopolize the attention and resources of multiple men. When men knew there was a sexual rival, they made more effort to satisfy their female partner and women orgasmed more frequently. 

H/T Rolf Degen at the usual loco.