Really old poop yields really new microbes – and new medical treatments.

Omaha digs deep for a story on how millennia-old feces has reintroduced us to some long-lost germs in the human gut biome – that might be able to help heal modern humans:

Previous research has made a connection between preindustrial diets, greater diversity in the gut microbiome and lower rates of chronic illnesses, and the team set out to find reconstruct ancient human gut microbiomes to investigate this link, said researcher Aleksandar Kostic of the Joslin Diabetes Center in Boston.

Research in the field has been held back by a lack of well-preserved DNA samples, but the team were able to perform a detailed genetic analysis of eight human feces samples found in Mexico and the southwestern United States, which date from 1,000-2,000 years ago.

The feces were “exquisitely preserved” thanks to the extreme aridity of the desert areas where they were found, Kostic said.

Researchers reconstructed a total of 498 microbial genomes and concluded that 181 were from ancient humans. Of those, 61 had not previously been found in other samples.

While research is at an early stage, Kostic hopes the microbes reconstructed by the team could eventually be used to reduce the rate of chronic conditions such as obesity or autoimmune diseases.

“We could reseed people with these human-associated microbes,” he said.

Research in the field is advancing, said Kostic, with some fecal microbic transplants working toward approval from the U.S. Food and Drug Administration.

The plan is to first see if the rediscovered microbes are in fact present in nonindustrial populations alive today, and then introduce gut biomes from nonindustrial people into animals to see how they are affected.

You can read the research here, in Nature.

[via Outside‘s newsletter]