Forget trekking to the Amazon; new and mysterious species await discovery much closer to home. A new project is revealing the previously unknown inhabitants of our belly buttons.
The Belly Button Biodiversity project wants to know what miniscule organisms live on us and what we can learn from them. After analyzing swabs taken from 92 participants, researchers have found at least 1,400 species of bacteria — a number they say is conservative.
"About 600 or so don't match up in obvious ways with known species, which is to say either they are new to science or we don't know them well enough," said Rob Dunn, an associate professor in the North Carolina State University biology department, and the belly button principal investigator.
"The crazy thing about these species (is) we are discovering new things that are living on people. They are right there, incredibly close to us," Dunn said. [Gallery: Bacteria in Your Belly Button]
Once the researchers have the belly-button samples, the team runs a genetic analysis to determine the species present. They also attempt to culture the microbes in petri dishes; however, this technique doesn't work for many species, because they don't like the microbe food in the dishes. In fact, scientists have no idea what many of these species eat.
Some belly-button inhabitants are familiar, even if you don't know their names. For instance, Bacillus subtilis, known to cause foot odor, also lives in some people's belly buttons.
"I would predict those people have feet-smelling belly buttons," Dunn said.
The ongoing analysis has shown that belly buttons contain many species, but that a substantial number of those species are common to many people, he said.
While we know very little about the fauna on our skin, it's clear that microbes can be helpful, acting as a first line of defense against infectious bacteria. For instance, when antibiotics clear the gut of these beneficial bacteria, the potentially colon-inflaming bacterium Clostridium difficile can establish a foothold, according to the Mayo Clinic.
In addition to collecting samples, this project is also part of an effort to pique people's interest in the surprisingly mysterious things that live on and around us.
To date, the project has collected more than 400 samples. The researchers are currently overwhelmed by those wishing to share the contents of their belly buttons. Anonymous photos of petri dishes with their fuzzy contents are posted online.
On Friday (Aug. 12), Nina Roundtree, an undergraduate student working on the project, is scheduled to discuss the project and its results to date at the Ecological Society of America's annual meeting in Austin, Texas.
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