Abstract
We have long known that microbes associate with all sorts of environments and organisms on Earth, but the advances in sequencing technologies are driving a sharp increase in research characterising the microbial communities of the most diverse animals. With this increase in study numbers comes a better understanding of the key roles that microbiomes play in their associated animals, and some level of support for the controversial holobiont concept: organisms, along with their microbial associates (and all their genes), are considered as a single evolutionary unit. Molluscs, with their wide distribution and remarkable diversity, represent a huge opportunity to further our understanding of the ecological and evolutionary roles of microbiomes. In this talk, I will present a brief overview of the current ‘molluscan microbiome’ research field, identifying the most studied molluscan classes, most used approaches and most researched topics. I will then present a case study on the potential impact of different trematode parasites on the microbiome of the New Zealand mud snail (Zeacumantus subcarinatus). This snail species is the first intermediate host of various trematode species, all of which will then infect small crustaceans and finally birds. We detected differences in the microbiome of snail hosts infected by different trematode species, all collected at the same time and place. We propose that the snails could have different microbiomes prior to trematode infection, which would make them more susceptible to different trematode species; in addition, the trematode-snail interaction could be responsible for snail microbiome changes post-infection. Considering the importance of parasitism not only to the parasitised host but also to the ecosystem, the microbiome role in host-parasite dynamics (e.g., leading to differential host fitness or parasite success) may have implications beyond the holobiont, at the ecosystem level.
Oral presentation.