Friend of the blog Cackle of Rad was the first person to send me this paper, and when I first tried to read it, I got...pretty angry. Being a rather obsessively logical person, I know why I felt angry about this paper, and I worked very hard to step back from it and approach it in a thoroughly scientific manner.

It didn't work, I called in Kate. That helped a little.

In the end, it's not a bad paper. The data are the data, as my graduate advisor always says. But data need to be interpreted, and interpretations require context. And I think what's missing from this paper is not data or adequate methods. It's context.

Smith et al. "Maternal tendencies in women are associated with estrogen levels and facial femininity" Hormones and Behavior, 2011.

And Kate agreed to cover the paper with me! Make sure you head over to her blog and check out her thoughts on the subject.

Scientists have always been interested in what makes women women, and what makes men men. Not just from a physical perspective. What gives rise to behaviors that we generally associate with masculinity or femininity? Are these behaviors rooted in biological differences? Is the way we view men and women more than just a result of upbringing?

In this particular case, the scientists were interested in how biological expressions of being "female" correlated with things like desire to have children, and how many children women wanted. So they grabbed a large number of women, and asked them how many kids they wanted. They took blood levels of estrogen (for four straight weeks to get in cycle variations, good going there), as well as rating how FEMININE the girls' faces were.

Now you might think, how can we determine whether a face is feminine? Well there are certain facial features which correlate with high levels of estrogen during puberty. Things like a small and pointy chin, larger and wide set eyes, a back set brow ridge, full lips. See here:

They found in a series of two experiments that higher levels of estrogen correlated with an expressed desire for more children, and higher ratings of facial femininity correlated with an expressed desire for more children. High levels of biological feminization correlate with an expressed desire for kids.

Now, correlation is not causation. So let's keep that in mind. Doesn't mean less "feminine" ladies are going to want fewer kids ALL the time and vice versa. When you keep that in mind, this paper's not really a big deal.

What bugs me about it, and other papers of its type, is that there are so many sociological factors that are never taken into account. For example, are women with more feminine faces expected to behave in ways that are more socially acceptable? Are they told more often that they would be good mothers? Are they punished more often for behaving in ways that are less "feminine"? Are they rewarded for more feminine behaviors?

After all, as the authors note themselves, women who appear more feminine tend to achieve lower overall rank in the workplace. They make less, they possess fewer "masculine" traits. But is this all due to a desire for teh babiez? Is it due to them just being biologically GIRLY and they just can't HELP it?!

I don't think so. Correlation ain't causation. I looked for studies but had a tough time coming up with anything, but are women who are more "feminine" looking perhaps PERCEIVED as less effective in the workplace? Are young girls who look more feminine encouraged to be compromising and passive as opposed to developing more "competitive", "masculine" traits? Maybe this is as much to do with how feminine features are PERCEIVED, and thus how these women are encouraged to behave, as it does with blood levels of estrogen. Heck, maybe more.

So I wonder if the authors should make more effort to look into sociological factors. How does the intense pressure on women to become wives and mothers change as a function of how feminine the girl looks? I think you can't separate any of this from this whole "women with higher estrogen want to be mothers" idea. This is why papers like this bug me, because they try to sell this as a evolutionary thing, without really acknowledging how much sociological pressure goes in to making women want to be mothers. And of course now I read them and I instantly get bristly, because what I see is people making assumptions about what I want, and what I must feel like, based on a few aspects of my physiology. It can be of value scientifically...but I don't want it to apply to ME. I know it might be science, but I also find it more than a bit insulting.