A roller derby tournament seems like a brutal research environment: women crash around a rink in short skirts and skates, slamming their shoulders into members of the opposing team so that their own team’s “jammer” can lap them and score. But it’s perfect for researchers investigating how, through skin-to-skin contact, we might colonize other people with the microorganisms that colonize us.
When curious researchers armed with cotton swabs and strong stomachs sequence DNA from microorganisms gathered from our armpits, belly buttons, and various other locales, both inside and outside us, they find miniature versions of ecosystems like those in rain forests and meadows, composed of trillions of microbes. In aggregate, this invisible mass of organisms is our “microbiome,” and it makes up as much as three pounds of our body weight.
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