Stability and flexibility of the gut microbiota of wild Tibetan macaques

The gut microbiota of wild animals is characterized by both stability and adaptive shifts in composition and prevalence in response to variation in food availability, nutrient intake, host physiology, temperature, and rainfall. Here, over a 12-month period, we investigated seasonal interactions between diet, weather, and gut microbiota in a wild group of Tibetan macaques in Huangshan by recording feeding behavior, monitoring weather, and analyzing 209 fecal samples using plant DNA metabarcoding (trnL region) and 16S rRNA gene sequencing. Based on the field observations and plant DNA metabarcoding, results revealed marked seasonal shifts in plant types and species consumed by Tibetan macaques. Despite dietary variability, only two enterotypes were presented throughout the year and gut microbiota composition exhibited lower dissimilarity within and across seasons compared to diet, except in autumn when low dietary diversity correlated with reduced microbial diversity. In addition, we also found that the enrichment of seasonal indicator bacterial genera and functions was related to the temperature or the nutrients of the food consumed by Tibetan macaques during that season. This study highlights the microbiota's resilience and metabolic plasticity in buffering seasonal dietary shifts, underscoring its role in maintaining host energy homeostasis under fluctuating resource availability.