Seasonal changes in the transcriptome of bat eyes reveal adaptive changes to exploit summer twilight

Seasonal fluctuations in visual perception are documented in many species, including humans, but the mechanisms and ecological significance of these adaptations often remain obscure. Depsite limited knowledge of bat visual ecology relative to hearing, the diversity of bat species makes them useful models for studying sensory adaptation mechanisms.

Here we analyze daily and seasonal changes in gene expression in the eyes of a temperate echolocating bat, the Mexican free-tailed bat (Tadarida brasiliensis). A total of 44 wild-caught bats were sampled from the same location across all four seasons, with whole eyes sequenced for total mRNA expression. Expression patterns were analyzed using differential expression analysis and clustering techniques for identifying correlation networks and evidence of cyclical enrichment.