What Lives in Your Belly Button? Study Finds “Rain Forest” Of Species



Rob Dunn and a team of ecologists have undertaken a study on just what can be found inside people’s belly buttons.

What they found even surprised them.

The study consisted of 60 volunteers belly buttons and microbial content could be found lurking inside. What they discovered is our belly buttons are a lot like the rain forest.

They found that people’s belly buttons are an area that doesn’t get as much attention when it comes to hygiene as the rest of our bodies.

Our skin has its own ecosystem, and this research allowed them to see just what the modern human microbial landscape consists of.

The researchers handed out swabs to the 60 volunteers who found the idea a little gross to say the least.

Welcome to the Jungle

From the 60 belly buttons, the team found 2,368 bacterial species, 1,458 of which may be new to science.

Some belly buttons harbored as only 29 species and whereas others had up to 107, although most had around 67.

Ninety-two percent of the bacteria types showed up on fewer than 10 percent of subjects, most of the time, they appeared in only a single subject.



One volunteer, for instance, apparently harbored a bacterium that had previously been found only in soil from Japan where he has never been.

Another, more fragrant individual, who hadn’t washed in several years, hosted two species of so-called extremophile bacteria that typically thrive in ice caps and thermal vents.

Although not a single strain showed up in each subject, eight species were present on more than 70 percent of the subjects. And whenever these species appeared, they did so in huge numbers.

“That makes the belly button a lot like rain forests,” Dunn said. In any given forest, he explained, the spectrum of flora might vary, but an ecologist can count on a certain few dominant tree types.

“The idea that some aspects of our bodies are like a rain forest to me it’s quite beautiful,” he added. “And it makes sense to me as an ecologist. I understand what steps to take next; I can see how that works.”

Method to the Madness?

Predicting which species call the human body home is only the first step. To make the knowledge useful, scientists need to know why these bacteria show up.

“We’re all like the guys before Darwin who went out and brought this stuff on the ship and said, Check out this totally weird bird this has got to be important!

“They were still so far from understanding the big picture,” Dunn said. “That’s where we are.”