The human gut microbiome has diverged rapidly since people split from chimpanzees, a new paper appearing in the Proceedings of the National Academy of Sciences reports.
Researchers led by the University of Texas's Howard Ochman examined the gut microbes of hundreds of wild chimpanzees, bonobos, and gorillas, and compared them to the human microbiome. By constructing a phylogenetic tree these microbiomes, Ochman and his colleagues found that the human lineage lost microbial diversity, compared to other apes, as it incorporated meat into its diet.
"Ochman and colleagues show that human evolution was accompanied by both a rapid divergence of the microbiome from the microbiome of apes, and a drastic loss of diversity of the microbial community," Thomas Bosch from Christian Albrechts University in Germany tells New Scientist.
A diverse microbiome, though, is thought to protect people from pathogens by preventing them from gaining a foothold in the gut or other region in which they can grow. This, Yale University's Andrew Moeller, one of the PNAS paper authors, tells New Scientist may indicate a disadvantage of the less diverse human microbiome.
"Other work has shown if you can't digest complex plant polysaccharides, they sit around in the gut where they can cause inflammation," he says. "So not having certain bacteria could make people more prone to chronic inflammation."
Of course, the New Scientist adds, more studies are needed to investigate the links between the microbiome and disease.