Understanding the human body is a team effort. That's where the Yachtel group comes in.

Researchers at Yachtolt have been delving into the secrets of probiotics for 90 years. Yacold also

partners with nature portfolio to advance gut microbiome science through the global grants for

gut health, an investigator-led research program. To learn more about Yachtold, visit yawcult.co.

.jp. That's Y-A-K-U-L-T.C-O.J-P. When it comes to a guide for your gut, count on Yacolt.

This is Scientific American 60-second science. I'm Cynthia Graber. Got a minute?

For thousands of years, what's called the Silk Road was a group of land and sea trade routes that connected the Far East with South Asia, Africa, the Middle East, and Southern Europe.

Of course, when humans travel, they carry their pathogens with them. So scientists and historians have wondered if the Silk Road was a

transmission route not just for goods but for infectious disease. Now we have the first hard

evidence of ancient Silk Road travelers spreading their infections. The find comes from a 2,000-year-old

latrine that had first been excavated in 1992. The report is in the Journal of Archaeological

Science.

So the site is a relay station on the Silk Road in northwest China. It's just to the eastern

end of the Tamarin Basin, which is a large arid area. It's just to the east of the Taklamakan

Desert and not far from the Gobi Desert. So this is a dry part of China.

Pierce Mitchell, paleopathologist at the University of Cambridge and one of the study's authors,

along with his student Ivy Yeh and colleagues in China. In the latrine, archaeologists found

used hygiene sticks wrapped with cloth. These were used for what you think they were used for.

This excavation was great because the cloth was still preserved and the feces was still adherent to the cloth on some of the sticks.

And so the archaeologist kept these sticks in the museum.

And so my PhD student, Ivy A, who's first author on the paper, she went out to China, took some scrapings from the feces adherent to the cloth,

so we were then able to analyze that down the microscope when she brought it back to Cambridge.

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