You want a slow-news-day Friday afternoon conversation-starter? You got it.

A lot rests here on how one defines “comfortable,” no?

Oxford University scientists investigated how comfortable people are being touched. In the largest-ever study on physical contact, they asked nearly 1,500 men and women from Britain, Finland, France, Italy and Russia to color in human body outlines to show which parts they would allow someone to touch, front and back.

Not surprisingly, they found that the more you know someone, the more likely you are to be happy to be touched by him or her.

Erogenous zones, however, were out of bounds to all but partners, with one exception.

Men indicated they were comfortable with female strangers touching any part of their body, even their genitals. In fact, a woman they barely know has “touching rights” similar to a parent and more than a sibling, according to the journal Proceedings of the Royal Academy of Sciences.

Follow the link and eyeball the diagram at the top of the page to see how comfortable men and women are being touched by various relations, back and front. Yellow means “very comfortable”; as you get into darker shades of red, all the way up to jet black, the comfort level decreases. Here’s the no-go zone for women vis-a-vis female and male acquaintances and strangers, respectively:

Logical and straightforward. Hands off the sexy bits, and if you’re a male stranger, you’d better relegate yourself to the far extremities. Even then, touching a woman’s feet rates as highly uncomfortable, which also makes sense. Since some people sexualize feet, and since there aren’t many casual “hey, lemme grab that foot” moments in polite company, a woman might rightly assume that any stranger who’s eager to touch hers is and can only be a leering creep.

Now for guys. The colors look … different.

A hand on the shoulder from a male stranger will be grudgingly tolerated. A hand nearly anywhere else is asking for a fight. A female stranger, though, can conceivably get away with a hand anywhere — even there, although that dark shade of red proves that the word “comfortable” in the excerpt above isn’t quite right. It’s not comfortable. It’s just not taboo. How come?

The answer, I assume, is that a strange woman assaulting a man that way isn’t the sort of physical threat that a strange man who’s assaulting a woman the same way is. If a male stranger crosses that line with a woman, it implies that he’s willing to cross every line. That’s terrifying. A female stranger doing the same to a man isn’t the same physical threat so the thought of it isn’t traumatic. Nor, of course, do men have to live with the risk of a member of the opposite sex getting grabby the way women do. Ask a group of guys to imagine a scenario in which a strange woman decides to grab a handful and they’re apt to envision it, I bet, either as part of a fantasy or as some sort of goofy sex comedy a la “American Pie.” Ask a woman to imagine a strange man groping her and the scenarios will trend darker. Although that raises another question: If this is ultimately about fear, or the lack of fear, of being overpowered by an insistent pervert, why do women also have strong no-go zones towards female strangers? You can hash that out in the comments.

One more contrast for you, this time involving how the two sexes regard touching by friends. If you’re a man, you’re not real thrilled with being touched by either male or female friends — but there are no official hands-off zones for the ladies:

Now here’s the shocker. When women are asked to say where they’re comfortable being touched by male and female friends, they say … this:

If you take that seriously, not only are there zero hands-off zones for male friends but women are actually more comfortable overall being touched by friends of the opposite sex than men are. That seems … unlikely. Or else intersex friendships abroad have taken a very unusual turn this century.