Some Plaque To Build A Theory On: Did Humans And Neanderthals Kiss?

The French kiss may be Neanderthal.

This week a team of scientists published a paper in Nature magazine about discoveries they made when they sequenced strands of ancient genetic material from the dental plaque of three Neanderthal men, who have been gone perhaps as long as 50,000 years.

Some of the Neanderthals were uncovered at a site in Spain, and one in Belgium. As you might expect, Neanderthal men did not floss. Flossing might seem unnecessary if your life expectancy is only between 15 and 30 years of age. So the fossilized plaque on their teeth and gums might disclose clues as to how Neanderthals lived, ate, worked, interacted with humans, and even loved.

The Neanderthal man in Belgium, according to his plaque, ate wooly rhinoceros, sheep, and mushrooms, and the Neanderthal guys in Spain ate moss, bark, and mushrooms, which sounds a lot like a packaged entree you could bring home today from Whole Foods.

The scientists also detected a microbial genome associated with gum disease. Laura Weyrich, a paleomicrobiologist at Australia's University of Adeleide who co-authored the study, told Nature magazine the presence of this genome could indicate that humans and Neanderthals kissed.

Deeply, madly, truly.

"If you're swapping spit between species, there's kissing going on," she said. "Or at least food sharing, which would suggest that these interactions were much friendlier and much more intimate than anybody ever possibly imagined."

But was it true love between humans and Neanderthals — or just a little shared slobber between species on the chewed leg of a woolly rhinoceros?

It turns out that just about every other animal species besides human beings manages to mate without kissing. In fact, only about 46 percent of human cultures kiss when they mate.

I think the other 54 percent look at their phones.

Adam Siepel, a biologist at the Cold Springs Habor Laboratory, told New Scientist he believes that once humans and Neanderthals began to live in the same geographical neighborhood on this planet, "it is likely that they drank from the same streams, perhaps salvaged food from one another."

Dr. Siepel doesn't sound like much of a romantic.

I prefer to think that humans and Neanderthals saw each other across a forbidding ancient landscape, and despite their differences, recognized a soul-mate.

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