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Comparing the diversity of gut microbiota between and within social insect colonies can illustrate interactions between bacterial community composition and host behaviour. In many eusocial insect species, different workers exhibit different task behaviours. Evidence of compositional differences between core microbiota in different worker types could suggest a microbial association with the division of labour among workers. Here, we present the core microbiota ofAphaenogaster piceaant workers with different task behaviours. The genusAphaenogasteris abundant worldwide, yet the associated microbiota of this group is unstudied. Bacterial communities fromAphaenogaster piceagut samples in this study consist of 19 phyla, dominated by Proteobacteria, Cyanobacteria and Firmicutes. Analysis of 16S rRNA gene sequences reveals distinct similarity clustering ofAphaenogaster piceagut bacterial communities in workers that have more interactions with the refuse piles. Though gut bacterial communities of nurse and foraging ants are similar in overall composition and structure, the worker groups differ in relative abundances of dominant taxa. Gut bacterial communities from ants that have more interactions with refuse piles are dominated by amplicon sequence variants associated with Entomoplasmataceae. Interaction with faecal matter via refuse piles seems to have the greatest impact on microbial taxa distribution, and this effect appears to be independent of worker type. This is the first report surveying the gut microbiome community composition ofAphaenogasterants.
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Social Microbial Transmission in a Solitary Mammal
ABSTRACT Microbial transmission is hypothesised to be a major benefit of sociality, facilitated by affiliative behaviours such as grooming and communal nesting in group‐living animals. Whether microbial transmission is also present in animals that do not form groups because territoriality limits interactions and prevents group formation remains unknown. Here, we investigate relationships among gut microbiota, population density and dynamic behavioural and spatial measures of territoriality in wild North American red squirrels (Tamiasciurus hudsonicus). Periods of high population density predicted population‐level gut microbial homogeneity but individual‐level diversification, alongside changes in obligately anaerobic, non‐sporulating taxa indicative of social transmission. Microbial alpha‐diversity increased with more frequent territorial intrusions, and pairs with stronger intrusion‐based social associations had more similar gut microbiota. As some of the first evidence for social microbial transmission in a solitary system, our findings suggest that fluctuations in density and territorial behaviours can homogenise and diversify host microbiomes among otherwise non‐interacting animals.
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- PAR ID:
- 10626527
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 28
- Issue:
- 8
- ISSN:
- 1461-023X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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