Overview
- Researchers report in Molecular Ecology that Seychelles warblers who spend the most time together share more anaerobic gut bacteria.
- The closed Cousin Island setting let scientists track every bird for years with colored leg rings and repeated fecal sampling.
- Breeding pairs and nest helpers showed the greatest similarity in gut bacteria, matching the long hours they spend together at the nest.
- These bacteria cannot survive in air, so the overlap points to transfer through close contact and shared nests rather than the wider environment.
- Scientists and outlets note possible parallels for people living together, since these oxygen‑shy microbes aid digestion and immunity, though this study did not test humans.