Most psychology research that deal with gay men dichotomize the sex roles as Top and Bottom (if they differentiate among gay men at all) - preference for insertive anal intercourse and preference for receptive anal intercourse respectively. The following article summarizes a study that tested a more elaborate categorization, and finds that sex role preference is correlated with differences in physical preferences for a sexual partner among gay men, suggesting that the hypothesized categorization is meaningful. The data suggests that sex roles should be thought of as a continuous spectrum that map onto a continuous spectrum of physical preferences.
The categorization tested includes 6 categories:
1) Only Bottom
2) Versatile, but prefer Bottom
3) Versatile, equal
4) Versatile, but prefer Top
5) Only Top
6) Never had anal sex / Don't Know
All volunteers were recruited over the period of 1/25/15 to 1/27/15. They were asked to participate in an online questionnaire. A total of 396 respondents completed the survey. The average age of respondents was around 33:
The average self-reported height of respondents was 5'10, and the average weight was 180 lbs. Both these statistics closely match national averages for men above the age of 20 - 5'9 and 180 lbs respectively.
Here is the distribution of how respondents categorized themselves into the more elaborate sex role categories:
Many gay men feel that there are more Bottoms than Tops, and the point of the study wasn't to prove this one way or another, but the point of the study was to see whether preference for certain physical traits were different among individuals among the different categories rather than finding out the actual distribution.
The data showed that while most gay men preferred men who were around their age, gay men who identified as Only Bottoms prefer significantly older men than Only Tops. Notice that the distribution is negatively skewed for Only Tops and is positively skewed for Only Bottoms. The 3 Versatiles have a normal distribution centered on "Around my Age", and were not significantly different from each other.
We see the same trend in height preference. Only Tops prefer significantly shorter men than Only Bottoms who in turn tend to prefer significantly taller men.
When asked to indicate the desired weight for a male who is 5'11, Only Tops preferred significantly lighter men than Only Bottoms who preferred significantly heavier men.
And finally, we see the same trend for preference for hairiness. Only Tops are significantly more likely to prefer smooth men than Only Bottoms who tend to prefer very hairy men.
In a pilot study with only 20 subjects and a dichotomized sex role preference, Damon (2000) found trends that power motivations correlated with sex role preference. In particular, he suggested that men who prefer insertive anal intercourse like to exert power over their sexual partners during sexual intercourse, while men who prefer receptive anal intercourse like to be overpowered.
Data from the current study supports this theory. Age, height, weight and hairiness are indicators of masculinity. Older, hairier, taller and more solid men are considered to be more masculine than younger, smoother, shorter and lighter men. Data from the current study suggests that Only Tops seek out sexual partners with less masculine features, while Only Bottoms seek out sexual partners with more masculine features. One might suggest that Only Tops seek out sexual partners with feminine qualities while Only Bottoms seek out sexual partners with masculine qualities.
Respondents were also asked whether they preferred their sexual activities to be gentle, rough or in-between. It was found that Only Bottoms and Versatiles (prefer Bottom) were more likely to prefer rough sex than the other 3 categories, again suggesting that receptive anal intercourse is linked with a desire to be overpowered.
Not only does the data show significant differences in physical preferences between Only Tops and Only Bottoms, but the data also shows that the 3 Versatiles, for the most part, modulate between these two extremes in a fairly linear manner. For example, consider this excerpted height preference table:
So if we think of Only Tops as preferring feminine traits and Only Bottoms as preferring masculine traits, then we have evidence that the more a gay man prefers the Bottom role, the more he prefers masculine attributes (older, taller, heavier, hairier) in a partner, and the more he prefers the Top role, the more he prefers feminine attributes (younger, shorter, lighter, smoother) in a partner.
Critics may point out that maybe Bottoms who prefer older partners become Tops who prefer younger partners as they get older, or that Tops in general are older than Bottoms. An ANOVA using sex role preference as the grouping variable and age as the dependent variable found no significant age difference between the 5 sex role groups. Also, Weinrich (1992) showed that early childhood play preferences were good indicators of sex role preference in adult gay men. These two sets of data together imply that sex role preferences among gay men are determined early in life and do not change.
In conclusion, instead of the Top and Bottom dichotomy, the data shows that there seems to be a fairly continuous spectrum of sex role preferences among gay men that map fairly consistently onto a continuous spectrum of physical preferences. Of course, the bigger question now is what biological or developmental differences map onto sex role preference, and what leads some gay men to prefer insertive anal intercourse rather than receptive anal intercourse.