Investigating human sperm competition in post-industrial ecologies: Cues to sperm competition predict pornographic DVD sales rank.
McKibbin, W.F., Pham, M.N., & Shackelford, T.K.
Sperm competition theory has been used to generate the hypothesis that men prefer to view pornographic images suggesting the presence of a rival male, over images which do not. The current research uses a new methodology to address conflicting evidence about men’s preferences for pornographic images. Raters coded a random sample of 166 pornographic DVDs (from a population of 49 493), which were then analyzed using multiple regression. Consistent with the hypothesis generated from sperm competition theory, the number of images on a DVD cover and screenshots depicting 2 or more men interacting with 1 woman (suggesting the presence of sperm competition) predicts DVD sales rank, whereas the number of images on a DVD cover and screenshots depicting 2 or more women interacting with 1 man (suggesting the absence of sperm competition) does not predict DVD sales rank. Discussion addresses limitations and future directions, including using penile plethysmography to avoid relying on correlational analyses.