We’re excited to share some of Libby’s dissertation research, just published in Molecular Ecology: Host-Microbiome Associations in Livebearing Fishes Adapted to Toxic Environments Rich in Hydrogen Sulfide.
In this study, we explored how livebearing fishes from the Poecilia mexicana species complex manage to survive in some of the harshest environments on Earth—streams filled with toxic hydrogen sulfide in southern Mexico. While microbes are known to aid invertebrates living in extreme places, similar partnerships in vertebrates haven’t been well understood. So, we set out to find whether the fish’s gut microbes might play a role.
Using 16S rRNA sequencing, we found that the gut microbiomes of fish living in toxic sulfide springs were consistently different from those in non-toxic habitats. Even more exciting, these differences showed up repeatedly across separate fish populations that independently adapted to these extreme environments. Some of the microbes we identified have been linked to helping hosts tolerate extreme environments before—suggesting they might be key players in the fish’s survival.
This work highlights how shared environmental pressures can shape host-microbe partnerships and opens up new possibilities for studying how vertebrates and their microbiomes evolve together in extreme habitats.
Check out the full paper at Molecular Ecology!