Cesar Fortes-Lima

When our ancestors left Africa and spread across the world, they carried not only their genes but also thousands of microorganisms living in their gut. 🧬🦠 A new @Nature study explored whether the evolutionary history of gut bacteria follows human migrations. Researchers compared the gut microbiomes of the Hadza hunter-gatherers from Tanzania and the Tsimane farmers and hunter-gatherers from Bolivia. Surprisingly, 87% of microbial species were shared between these populations. Many of these bacteria are now extremely rare in industrialized societies, suggesting that we may be losing part of our ancient microbial heritage. Whether this affects our health remains unknown. But the most fascinating result came from comparing bacterial genomes. Despite sharing the same species, their bacterial strains were genetically distinct. Using bacterial recombination patterns and population genetic modeling, researchers estimated that these bacterial populations became isolated around 17,000 years ago. Remarkably, this roughly matches the period when humans first settled the Americas. A beautiful example of how ancient human migrations left traces not only in our DNA but also in the genomes of bacteria living inside us. nature.com/articles/s41586-0… #microbiome #gut #evolution