Aneri Pattani reports via The New York Times (Warning: source may be paywalled; alternate source): Couples who live together share a lot of things: beds, bathrooms, food, toiletries. But one thing they might not expect to share? Skin bacteria. In a study published Thursday in mSystems, an open-access journal of the American Society for Microbiology, researchers studied the skin microbiomes of 10 sexually active, heterosexual couples living together. A microbiome is a mini-ecosystem of bacteria, fungi, viruses and other microorganisms living on and in the body. Each square centimeter of skin hosts between one million and one billion microorganisms, according to the study. After analyzing 330 skin swabs collected from 17 parts of the body on each participant, the researchers found that each person significantly influenced the microbial communities on a lover's skin. In fact, computer algorithms relying on microbial data were able to accurately match couples with up to 86 percent accuracy.