Male-biased immune ageing in a polygynous bat

Yet, little is known about the relationship between these two characteristics, or the extent to which they vary between individuals of the same species. We investigated sources of immune variation in wild greater spear-nosed bats, Phyllostomus hastatus, via transcriptome sequencing of blood samples before and after ex vivo exposure to lipopolysaccharide, a membrane component of gram-negative bacteria.

We estimated bat ages from a combination of banding records and a methylation clock. We assessed immune variation across both sexes, males of contrasting social status, and the full range of ages in each sex. We observe striking immune variation associated with sex and age, with males and older bats mounting stronger inflammatory responses.