Aim: Patterns of separation among males and females, known as sexual segregation, traditionally correlate with elevation or latitude in animals. Alternatively, in humans, spatial and behavioural segregation are driven by inherent sex-based differences in thermal preference, although their cause and adaptive value of these differences remain unclear. Here, we explore whether, similar to humans, ambient temperature can explain patterns of separation among males and females in endotherms. 

Location: Israel.

Time period: 1981 – 2018.

Major taxa studied: Migratory sexually dimorphic birds (13 species) and bats (18 species).

Methods: We calculated the proportion of males and females at each sampling site for each bird or bat species. We used general linear mixed models (GLMM) to quantify the variance explained by elevation, latitude, body size and ambient temperature, and corrected for phylogeny, site and year. We employed model averaging over the best models by comparing corrected Akaike information criterion.

Results: We found a correlation between geographic separation and temperature that accounts for variance in the data that is not explained by elevation and latitude. We show that temperature was negatively correlated with the proportion of males in bats and birds, whereas body size only explained this response in birds.

Main conclusions: Our findings suggest that females are found in higher ambient temperatures. We term this Differential Sex-related Thermal Preference (DSTP) and propose that it is a broad phenomenon common in many endotherms, acting as a significant force shaping dispersal, sociality, and behaviour of animals and should be explored from this wide perspective.

The readme file contains an explanation of each of the variables in the datasets, appropriate references, and - if it concerns a derived variable - the way it was calculated from the primary data. #NA =  values not available. Information on how the measurements were done can be found in the associated manuscript referenced above.