Bats, Bacteria and Bat Smell V.2.0: Repeatable Sex-specific Differences in Scent Organ Microbiota

Abstract

Background: Reproducibility is a fundamental principle in science, ensuring reliable and valid findings. However, replication studies are scarce, particularly in ecology, due to the emphasis on novelty for publication. We explored the possibility of replicating original findings in the field of microbial and chemical ecology by conducting a conceptual replication of a previous study analysing the sex-specific differences in the microbial communities inhabiting the wing sacs, a scent organ with crucial functions in olfactory communication, of greater sac-winged bat (Saccopteryx bilineata). In the original study, the skin swabs from the antebrachial wing sacs of the males and wing sac rudiments of the females were collected and analysed using culture-dependent methods to test sex-specific differences. The authors demonstrated that males have lower microbial richness and different microbial composition than females. Recent molecular techniques offer improved accuracy in pinpointing microbial members than culture-dependent methods because only a limited proportion of the symbiotic microbiota is cultivable. For this reason, we attempted to reproduce these findings using 16s rRNA sequencing and advanced statistical methods. Results: Our study corroborated the original study's findings: Males had a lower microbial richness, and the community composition differed between the sexes. Furthermore, in the current study, males had an increased abundance of bacteria that might potentially be involved in odour production and degradation of malodorous substances and antimicrobial production. Conclusions: Our conceptual replication study on the wing-sac microbiota of S. bilineata validated the original findings, corroborating that microbes can play a role in shaping their host's olfactory phenotype and consequently influence sexual selection. Furthermore, the current study emphasises the importance of replication efforts and hopefully encourages a culture that values replication studies in scientific practice.