Social networks predict gut microbiome composition in wild baboons

Area of Science:

• Microbiome research
• Primate ecology
• Social behavior

Background:

• Social relationships significantly impact health in humans and primates.
• The underlying mechanisms linking sociality and health, particularly via the gut microbiome, are not fully understood.

Purpose of the Study:

• To investigate how social relationships influence gut microbiome composition and function in wild baboons.
• To identify specific social factors driving microbial variation and explore microbial transmission pathways.

Main Methods:

• Shotgun metagenomic sequencing of fecal samples from wild baboons.
• Analysis of social network data, including group membership and interaction rates.
• Statistical modeling to correlate social variables with microbiome taxonomic and functional structure, controlling for diet and kinship.

Main Results:

• Social group membership and network relationships significantly predicted gut microbiome taxonomic structure and encoded gene content.
• Rates of social interaction directly explained microbiome variation, independent of diet, kinship, and shared environment.
• Fifty-one microbial taxa were identified as socially structured, with a notable enrichment for anaerobic, non-spore-forming bacteria.

Conclusions:

• Social interactions, particularly direct physical contact, are a key determinant of gut microbiome composition in natural animal populations.
• These findings have implications for understanding the health benefits of sociality and the evolution of group living.
• The study underscores the importance of social transmission in shaping host-associated microbial communities.