title: Temporal Stability and the Effect of Transgenerational Transfer on Fecal Microbiota Structure in a Long Distance Migratory Bird.
abstract: Animal bodies are inhabited by a taxonomically and functionally diverse community of symbiotic and commensal microorganisms. From an ecological and evolutionary perspective, inter-individual variation in host-associated microbiota contributes to physiological and immune system variation. As such, host-associated microbiota may be considered an integral part of the host's phenotype, serving as a substrate for natural selection. This assumes that host-associated microbiota exhibits high temporal stability, however, and that its composition is shaped by trans-generational transfer or heritable host-associated microbiota modulators encoded by the host genome. Although this concept is widely accepted, its crucial assumptions have rarely been tested in wild vertebrate populations. We performed 16S rRNA metabarcoding on an extensive set of fecal microbiota (FM) samples from an insectivorous, long-distance migratory bird, the barn swallow (Hirundo rustica). Our data revealed clear differences in FM among juveniles and adults as regards taxonomic and functional composition, diversity and co-occurrence network complexity. Multiple FM samples from the same juvenile or adult collected within single breeding seasons exhibited higher similarity than expected by chance, as did adult FM samples over two consecutive years. Despite low effect sizes for FM stability over time at the community level, we identified an adult FM subset with relative abundances exhibiting significant temporal consistency, possibly inducing long-term effects on the host phenotype. Our data also indicate a slight maternal (but not paternal) effect on FM composition in social offspring, though this is unlikely to persist into adulthood. We discuss our findings in the context of both evolution and ecology of microbiota vs. host interactions and barn swallow biology.
authors.affiliation: Department of Zoology, Faculty of Science, Charles University Prague, Czechia.
authors.forename: Jakub
authors.initials: J
authors.lastname: Kreisinger
authors.affiliation: Department of Zoology, Faculty of Science, Charles University Prague, Czechia.
authors.forename: Lucie
authors.initials: L
authors.lastname: Kropáčková
authors.affiliation: Department of Ecology, Faculty of Science, Charles University Prague, Czechia.
authors.forename: Adéla
authors.initials: A
authors.lastname: Petrželková
authors.affiliation: Institute of Vertebrate Biology, Czech Academy of Sciences, Studenec Czechia.
authors.forename: Marie
authors.initials: M
authors.lastname: Adámková
authors.affiliation: Department of Zoology, Faculty of Science, Charles UniversityPrague, Czechia; Institute of Vertebrate Biology, Czech Academy of Sciences, StudenecCzechia.
authors.forename: Oldřich
authors.initials: O
authors.lastname: Tomášek
authors.affiliation: Montpellier-SupAgro, UMR Centre de Biologie pour la Gestion des Populations Montferrier-sur-Lez, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Martin
authors.affiliation: Department of Zoology, Faculty of Science, Charles University Prague, Czechia.
authors.forename: Romana
authors.initials: R
authors.lastname: Michálková
authors.affiliation: Department of Zoology, Faculty of Science, Charles UniversityPrague, Czechia; Institute of Vertebrate Biology, Czech Academy of Sciences, StudenecCzechia.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Albrecht
keywords: barn swallow; fecal microbiota; gastrointestinal tract; metagenome; microbiome; symbiosis