People who live with canine companions — dog owners, some would call us — have certain common quirks: a fondness for wet kisses, for instance, and a compulsion to grab a fistful of fur and ask, "Who's a good boy (or girl)?" with no expectation of an answer.
A new study finds these dog owners are united, both with their dogs and each other, by similar microbiomes as well.
Researchers rounded up 50 families, half of them with one or more dogs living under the same roof, to see how living together was reflected in the cohabitants' shared "microbiota": the distinctive colonies of bacteria that live on our skin, in our mouths and in our guts.
The size and composition of those colonies is unique to each of us, almost like a fingerprint. But our microbiomes bear similarities to those with whom we share households, suggesting that, over time, couples don't just look more alike on the outside; as habitats for a veritable menagerie of microbes, they grow to look more alike on the inside too.