Eight years of feces reveals a lot about a primate: what it eats, its general health — and even how many friends it has.
In a recent study published in the journal Science Advances, UT professor Howard Ochman and his colleagues found that social chimpanzees have a more diverse group of microorganisms living inside their intestines than their lonelier peers.
In order to procure these results, the scientists sampled the DNA diversity in a chimpanzee’s fecal samples and watched each chimp to find the amount of time it spent with other members of its community. They did this experiment on forty chimps over eight years.
They used the DNA samples to identify the species in the chimp’s microbiome, which is a term that describes the microscopic organisms that live in and on larger animals.
The scientists found that these gut microbes are shared between members of primate social groups, not just from a mother to her offspring. It also suggested that chimpanzees in the same community have similar microbiomes.
These results are good news for chimps with a lot of friends. Many studies suggest that the more species of microbes live on an animal, the healthier the animal is. An absence of beneficial microorganisms increase the risk of infectious disease, according to a study in the journal Gastroenterology. In a study in Nature, scientists found that obesity is correlated with fewer species in the microbiome.
“People tend to think that diversity is good for you,” Ochman said.
In the United States, inadequate nutrition and antibiotics limit the number of species that make up microbiomes.
“If you’re eating a burger-and fries diet, you have less diversity in your microbiome,” Ochman said. “Populations that are indigenous to either South America or Africa, pre-industrialized places, have higher diversity.”
Sanitation, as well as diet, influences microbiome diversity. Unlike humans, chimps don’t use antibacterial soap after shaking hands or going to the bathroom. Anne Pusey, one of the authors of the study, said that the chimps often come into physical contact with each other during social interactions.
“They groom, they mate, they play,” Pusey said. “They brush through each other’s hair and fur, and they sometimes mouth the hair as well.”
While this contact has positive repercussions for the diversity of the chimp’s microbiomes, pathogens can spread this way as well. Ochman said that the dangers of spreading disease through unsanitary practices outweigh the health advantages of a diverse microbiome.
“Remember, these microbes can be a good thing, but you’re also spreading pathogens,” Ochman said. “You have to play both sides of it.”
Even if the scientists endorsed lower sanitation standards in light of these results, their advice might not catch on. Jasmine Bell, psychology sophomore, said that she would be reluctant to cease basic cleaning habits, even if she learned it could improve the diversity of her microbiome.
“Unless someone gives me some pretty compelling evidence to stop washing my hands, I’m not going to stop doing it,” Bell said.