Limitations
We only collected skin biopsies from the chest to limit the number of biopsies collected per individual during the capture-and-release. However, comparing chest skin gene expression to gene expression in a non-sexual skin area would allow us to assess (1) whether higher male expression associated with blood flow and vascularization is unique to chest skin biopsies and (2) whether both male and female chests are hotspots for expression of androgen and estrogen related genes. While we were able to identify interesting sex differences, we were not able to assess gene expression differences between male status categories because anesthetizing a leader male to collect a biopsy sample would put them at risk of losing their status. Lastly, we restricted our male chest photo dataset to only photos taken in March and April to match our more limited female chest photo dataset. This facilitated a more direct comparison between the sexes, but may have reduced our ability to identify more within-individual variation, particularly in males.