How does environment shape the evolution of gut bacteria?
A study of wild African herbivores offers new insight into how environmental conditions—not just diet and anatomy—can influence the evolution of gut microbes that play a critical role in animal health and well-being.
“There’s a concept in ecology called phylosymbiosis, which is basically the idea that as species evolve and diverge from each other, their gut microbiomes will also diverge in a predictable way,” says Erin McKenney, coauthor of a paper on the work and an assistant professor of applied ecology at North Carolina State University.
“But studies have found that this is not always the case,and it’s not clear why.”
“Our work hear was focused on determining whether there was evidence of phylosymbiosis among herbivore species,” mckenney says.
The researchers analyzed fecal samples from 11 herbivore species in Tanzania,including wildebeest,zebra,gazelle,and buffalo. They found that while diet and anatomy did play a role in shaping gut microbial communities,environmental conditions—specifically,rainfall and seasonality—were even stronger predictors of microbiome composition.
“We found that herbivores living in similar environments had more similar gut microbiomes, even if they were distantly related and ate diffrent things,” says Stephanie Kivlin, a postdoctoral researcher at the University of California, Berkeley, and lead author of the paper.
“This suggests that environmental filtering—where only certain microbes can survive in a given environment—is a major driver of gut microbiome evolution.”
The findings have implications for understanding how animals adapt to changing environments. As climate change alters rainfall patterns and seasonality, it could have significant consequences for the gut microbiomes of herbivores and, ultimately, their health.
“Gut microbes are essential for digestion,nutrient absorption,and immune function,” Kivlin says. “If the gut microbiome is disrupted, it can lead to a range of health problems.”
the study appears in the journal Ecology Letters.
Source: NC State University