I tend to think I'm a pretty nice guy. I even know the difference between an actual nice guy and a "Nice Guy"—someone who thinks niceness is just part of a transaction for which he should receive blowjobs. But while I consider myself a male feminist, woman-hating might be etched into the very contours of my body. I know this because a recent study out of McGill University has brought a horrifying reality to my attention: I have a finger length ratio that corresponds to a tendency to be quarrelsome with women.
The snappy title of the study in question is "Fetal exposure to androgens, as indicated by digit ratios (2D:4D), increases men's agreeableness with women." That "fetal exposure to androgens" part refers to a previous hypothesis that seems to be widely agreed upon. Namely: being exposed to high levels of androgens in utero—a bombardment in the womb of masculine hormones, including testosterone—has an effect on your finger length, specifically your index (2D) and ring (4D) fingers.
But this new study went a step further, pointing out what behaviors that hormone bath creates, and more specifically—in my case at least—what havoc a lack of such a hormone bath creates. The study involved monitoring subjects' behavior out in the world, not in a lab. It found the following:
Men were more agreeable towards women than men; this effect was significantly greater in those with smaller 2D:4D ratios. Men with smaller 2D:4D ratios were also less quarrelsome towards women than towards men.
Since I found the phrasing a little odd, I got a hold of Rachel Sutton, one of the authors, to find out what this means for me and my woman-hating hands. It turns out there might be some hope for me after all.
VICE: What's the background for this finger study?
Rachel Sutton: We looked at the ratio of the second and fourth digit, so the index finger and ring finger, which previous research shows is a marker of exposure to the level of testosterone that the fetus is exposed to. Previous research has shown that in men, specifically, a smaller digit ratio—meaning that the second finger is much smaller than the fourth—is associated with a higher level of dominance and greater reproductive success, like having more children.
But your study contradicted that?
We looked at those people's digit ratio, in men and women, and the personal behavior in daily life and we didn't find any significant associations in digit ratio in men and dominance. But we did find that men with the more masculinized—or smaller—digit ratio were more agreeable and less quarrelsome with the women that they interacted with. So that was more in like romantic partners, female colleagues, and friends. So this might explain why they have more children and we didn't have any association with women.
I have a ring finger that's slightly shorter than my index finger, so what does that mean for me?
Well how much shorter is it?
A tiny bit.
So that would be a less typically masculine ratio. That means that, on average, men with a digit ratio like that are less agreeable and more quarrelsome with women than men with more of a masculine ratio. It's not that every man with a smaller digit ratio is friendlier with woman and men with a larger digit ratio are less friendly, there are other factors.
How seriously should we take this?
I wouldn't judge someone solely based on their ratio, but it could be an interesting indication of the hormones they were exposed to in the womb. And it's interesting to know that, on average, men may be more or less likely to be friendly with women based on their digit ratios. There are for sure exceptions as well. So I wouldn't base it solely on digit ratio.
So it has to do with fetuses being exposed to hormones. What happened after I was exposed to these not-so-masucline hormones in the womb?
Well the idea is that the hormones in the womb can impact brain development. [Previous work has suggested] that women with a more feminine digit ratio had brain scans that looked more typically feminine. So the idea is that the hormones in the womb can impact brain development, and later in life could impact people's behavior.
Are there any other findings surrounding this?
It's mostly dominance and reproductive success that have come out of it. There's also spatial abilities.
Am I supposed to have worse spatial abilities based on my ratio? Because I have a terrible spatial sense.
Yeah, there's some evidence that people with more masculine ratios have better spatial abilities than people with more feminine ones.
The way you quantified agreeable behavior was by measuring compliments and smiles. Those seem superficial.
Well we measured dominance and agreeableness with different items. So those are basically items that in other research have been shown to indicate agreeable or warmer behavior. Like dominance, on the other hand, would be measured with something like expressing an opinion or directing other people in their activities. So those were specifically to measure agreeable behavior and they have been shown in other research to capture the degree of warmth and the degree of agreeableness in the interaction with another person.
Right, but how do you know those link up with agreeability?
We used a measure called the SBI, the Social Behavior Inventory, which is an item that's used for this type of study where people report on their daily interactions. This measure has been validated in a number of other studies to actually capture dominant behavior.
Well that sucks for me. What else do my fingers reveal about me?
I only know that it's used as a measure of androgen exposure in the womb, but I imagine there are other genetic effects as well. Again, it's on average that it's associated with androgen exposure in the womb. It's not to say that it's a perfect marker.
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