Insect-associated bacterial communities across an anthropogenic landscape.

Anthropogenic activities induce drastic changes in land use that are at least partly responsible for the ongoing global patterns of macro-biodiversity erosion. These habitat changes also impact the fitness of the resilient species, through direct effects on diet and/or indirect environmental effects. Although microbial communities associated with species can crucially influence a diverse set of their host's biological functions, studies on how microbial communities associated with wild species respond to habitat degradation remain scarce. We use metacommunities of two sympatric herbivorous insect species specialized in feeding on IMPORTANCE: This research dives into the impact of habitat degradation on bacterial communities associated with wild herbivorous insect species, utilizing the ecologically relevant and well-characterized fragmented landscape of the Åland Islands, Finland. This study is crucial as habitat degradation driven by anthropogenic activities (i.e., land use change and habitat fragment size) poses a growing threat to global biodiversity. Indeed, as microbial partners play a pivotal role in the ecology and adaptation of their host species to their environment, there is a pressing need to comprehend how the host-associated microbial diversity responds to their host environmental changes to evaluate their contribution to the escalating patterns of biodiversity erosion globally. However, despite extensive research on the impact of habitat degradation on macro-species, the effects on microbial communities remain an understudied aspect of species ecology.