Selection and transmission of gut microbiome alone can shift mammalian behavior
5 days ago
- #microbiome
- #evolution
- #behavior
- Animals live in partnership with their gut microbiota, which can shift when hosts adapt to new environments.
- A key question is whether host traits under natural selection can be transmitted solely through the microbiome, without changes to the host genome.
- Experimental evidence shows that selection on a behavioral trait in mice (locomotor activity) can significantly shift the host trait over time through microbiome transmission alone.
- Fecal transfers from wild-derived mouse strains into germ-free male recipients identified locomotor activity as transmissible through the gut microbiome.
- Four rounds of one-sided microbiome selection (transferring microbiomes from low-activity donors) led to a decrease in locomotion, linked to enrichment of Lactobacillus and its metabolite indolelactic acid (ILA).
- Administration of either Lactobacillus or ILA alone was sufficient to suppress locomotion in mice.
- The study demonstrates that microbiome selection and transmission can shape mammalian behavior independently of host genomic evolution.
- Microbiome-mediated trait inheritance plays a role in shaping host ecology and evolution.
- The findings support the idea that vertically transmitted microbes can contribute to heritable variation upon which natural selection can act.
- The study addresses limitations of previous research by including control treatments, replicates, and detailed microbiome and metabolite analysis.