While the fieldwork was probably less than fun, researchers recently discovered some important information about human health from an unlikely place — gorilla poop.

Researchers used genetic sequencing to analyze fecal samples from wild African apes living in the Sangha region of the Republic of Congo. The samples were collected by the Wildlife Conservation Society (WCS).

The research project was led by scientists at the Center for Infection and Immunity (CII) at Columbia University's Mailman School of Public Health. Findings appear in the journal Nature Communications.

Over the course of three years, the scientists worked to learn more about the gut microbes of gorillas and chimpanzees to compare them to existing microbes in non-human primates and humans.

They found that the primates' microbiomes fluctuate with seasonal rainfall changes and as their diets change, also based on seasons. The switch was most noticeable during the dry summer when fruits were aplenty and made up a large part of the animals' diet, as opposed to more fiber-rich leaves and bark in the other seasons.

The seasonal shifts are similar to microbiome changes in the human Hadza hunter-gatherers from Tanzania, who also rely heavily on the seasonal availability of foods in their environment. These shifts are less likely in the average person, as most produce is available year-round in supermarkets.

"We observed dramatic changes in the gorilla and chimpanzee microbiomes depending on seasons and what they are eating," said senior author Brent L. Williams, Ph.D, assistant professor of Epidemiology at CII. "Bacteria that help gorillas break down fibrous plants are replaced once a year by another group of bacteria that feed on the mucous layer in their gut during the months they are eating fruits.”

This research can help open doors to understand how the shifting microbes influence health and disease, which could aid in future disease prevention research.

"While our human genomes share a great deal of similarity with those of our closest living relatives, our second genome (the microbiome) has some important distinctions, including reduced diversity and the absence of bacteria and archaea that appear to be important for fiber fermentation," said first author Allison L. Hicks, MS, a researcher at CII. "Understanding how these lost microbes influence health and disease will be an important area for future studies."

Scientists also noted that the primates studied are endangered. As their homes are lost to deforestation, so are their food sources. Humans are not immune to similar issues, cautioned co-author Sarah Olson, Ph.D, associate director of wildlife health at WCS.

"We are losing biodiversity on a global scale," she said. "In fact, our own human microbiome is not immune to this phenomenon. There is an ever growing need for conservation efforts to preserve environments that are vital to the health of animal populations."

The study provided results that could fuel many more research projects to come.

"This study underscores the importance of a One Health framework in focusing not only on diseases but also on understanding more about normal physiology," said co-author W. Ian Lipkin, MD, John Snow Professor of Epidemiology and director of CII. "It also provides evidence to support the adage that you are what you eat."