What could the microbiomes of our ancestors look like and how did they evolve?
This research by biologists from North Carolina State University on the microbiomes of our ancestors offers hypotheses on the influence of microbes on our first daily and social lives. This work, presented in the journal Frontiers in Ecology and Evolution, suggests that the microbiome of our ancestors could have played a key role in human evolution. In particular, the adaptive capacity of the intestinal microbiome would have allowed human dispersal and adaptation in new geographic areas.
What did the microbiomes of our ancestors look like and how did they evolve, wonders here the team of Rob Dunn from North Carolina: “Medicine, diet and many other areas take more meaning in light of a better understanding of the microbes that were part of the daily life of our ancestors. ”
“Adaptive microbiomes” to better understand our ancestors
The microbiome adapts, the microbiome testifies: These adaptive microbiomes may have been essential to the survival and development of humans in a range of different environments. The team analyzed data from previously published studies to compare the microbiota in humans, great apes and other non-human primates. This analysis leads to the conclusion that there is a substantial variation in the composition and function of the human microbiome in correlation with geography and lifestyle. This suggests that the human gut microbiome has quickly adapted to new environmental conditions.
New living environments, new microbiomes: when our ancestors migrated to new geographic areas, they had to face new food choices and new diseases. They used different tools and processes to obtain and process food. Their adaptive microbiome had to digest new foods, protect against new bacteria. Microbial adaptation has therefore played an essential role in this human adaptation to new lifestyles.
The social sharing of microbes promotes new microbiotic models: the researchers point out that this social sharing of bacteria may have led to local microbial adaptations. Human-to-human sharing, but no doubt also of Man with food: the fermentation of food, which allowed our ancestors to store food longer, would thus have facilitated the persistence of human communities, consuming the same food together, and presenting over time the same microbiota: “We have outsourced our body microbes to our food,” write the researchers.
These hypotheses still need to be worked on by paleoanthropologists, doctors and biologists. However, this work opens the way to a new field of research, the analysis of our microbiomes as testimonies or signatures of our evolution and our lifestyles.