Testing Mate Choice Hypotheses in a Transitional Small Scale Population

Objective: Tests of theories of mate choice often rely on data gathered in White, industrialised samples and this is especially the case for studies of facial attraction. Our understanding of preferences for sexual dimorphism is currently in flux and a number of hypotheses require testing in more diverse participant samples. The current study uses opportunistically gathered facial dimorphism preference data from 271 participants in rural Nicaragua, and 40 from the national capital Managua. We assess pre-registered hypotheses drawn from sexual selection theory, and from more recent approaches which consider the impacts of economic development and cultural ‘modernisation’ on mate preferences. Methods: Participants verbally reported demographic data, and indicated preferences for five male and five female pairs of faces manipulated to differ in sexually dimorphic facial structure based on a sample of Salvadoran individuals. Results: While urban participants showed a preference for more feminine female faces, this preference was not evident in the rural participants. Neither urban nor rural participants showed any directional preference for masculinised/feminised male faces. Furthermore, there was no support for any other pre-registered hypothesis. Conclusions: Our results are consistent with previous studies showing no interest in facial dimorphism in less globally-acculturated, or market integrated, populations. Together, this suggests that while facial dimorphism may be subject to systematically varying preferences amongst some low-fertility, industrialised populations, it is not a feature which is likely to have been important in ancestral populations. We call for further work attempting to replicate well known mate choice phenomena in more diverse samples.