Pharyngula

Wow. Talk about major failure. A new study out correlates levels of Foxp2 with levels of vocalization in rats: basically, male rats squeak more than female pups when they’re stressed by separation from their mothers, and mothers tend to rescue the rat who squeaks the loudest. They then found higher levels of Foxp2 in males, and also found that reducing male Foxp2 levels in male pups with siRNA also reduced vocalizations. So far, so good; looks like a reasonable and interesting experiment. Then they extended it to humans half-assedly, finding that 4 year old boys have lower levels of Foxp2 in their left hemisphere (the side that largely controls speech) than 4 year old girls; they could not do the siRNA experiment in human children, obviously.

And that’s where it goes so, so wrong. The researchers assumed that women talk more than men, four-year old girls have more Foxp2, therefore their results conform neatly to what they observed in rats.

You know all the times that men complain about women talking too much? Apparently there’s a biological explanation for the reason why women are chattier than men. Scientists have discovered that women possess higher levels of a "language protein" in their brains, which could explain why females are so talkative.

Previous research has shown that women talk almost three times as much as men. In fact, an average woman notches up 20,000 words in a day, which is about 13,000 more than the average man. In addition, women generally speak more quickly and devote more brainpower to speaking. Yet before now, researchers haven’t been able to biologically explain why this is the case.

The only problem here is that that statistic is false, and men and women talk at about the same rate. Oops.

female-vs-male-word-counts

This is so unfortunate. There is evidence that girls on average learn to talk a little earlier than boys, and that would have been a safer correlation, especially since they’re describing different levels in young children. That interpretation is still fraught, though: they haven’t worked out cause and effect, they know nothing about how Foxp2 mediates this vocalization difference (and we don’t even know if it’s a direct effect on vocalization; it could also modulate a stress response), and in humans, we don’t know if different socialization pressures could be causing differences in the expression of this gene.

This is why scientists are supposed to be cautious in their interpretations. Especially when trying to explain human behavior, there’s far too much temptation to push the results to fit stereotypes as a kind of unconscious validation.

Comments

  1. #1 walid Mikhail MD
    st paul minnesota
    February 23, 2013

    The science stopped at the rats. The rest is conjecture. The medical literature if full of such nonesense and is called “science” and “evidence”. Even if such a population correlation exists, it can never be applied to an individual.

  2. #2 LadyAtheist
    February 23, 2013

    If the topic is sports, the guys talk a mile a minute and the women say “uh huh” occasionally. If the topic is Project Runway, it’s reversed. I think I deserve grant money for that observation!

  3. #3 Danilo Santos
    February 23, 2013

    very cool thi article http://www.designed.com.br

  4. [...] PZ is selective in the studies he attacks: I used to follow PZ all the time, hanging on to almost every word he wrote. Then he climbed on a soapbox and threw all objectivity out the window. I read the FoxP2 article as well and thought it was very feeble, not just in extrapolating to humans, but even in the methodology about mice. PZ adds nothing in his attack except cherry-picking some other data to make a political point. One of the pieces of dirty laundry in science is how many initial findings end up getting reversed. Of course in science the confirmation or disputing of results is what it’s all about, we don’t really “believe” something until extensive followup and/or duplication and/or contradictory studies are done (remember the faster-than-light neutrinos where the crowdsourcing fairly quickly revealed the flaw). So the more interesting thing to comment on, PZ, is not the political correctness campaign you’re on, but why science rushes to publication and then gets reversals. I’ve been critical of almost everything I find about nutrition because, frankly, most of it is wrong, and bad information, esp. trumpeted by the popular press is harmful, either directly or in impeding people to do the right thing since they have all the fad junk information. So why not talk about this, PZ? Why not find other articles that are bogus and attack them? Your outrage is getting really old and tiring. [...]

  5. #5 David
    February 24, 2013

    Males are 3 to 4 times more likely to have autism than females and not talk at all. Foxp2 is studied in relation to autism and language disorders, it is one of the hypotheses for the lack of language development in many people with autism.

    However, some reasearchers have extrapolated the findings in autism research (the clear and obvious gender differences) to suggests that wider gender differences between men and women might be explained by increased tendancy towards mild autistic traits in men, how such traits in men (if real) are extrapolated to culture, society and gross gender differences is the subject of heated debate and vehement disagreement. Some deny any gender difference at all, explaining that all differences are the result of bias, culture and tradition (i.e. the bank slate)

    However, the role of Foxp2 in language development should not be attacked by those with a political bias towards rejecting any notion of innate gender difference. It is an objective fact that autism occurs more often in males, it is at the tail of the bell curve where gender differences arise.

  6. #6 David
    February 24, 2013

    Also, one other thing. Regarding Fisher (2003), a corpus of thousands of telephone conversations.

    How many non-verbal and taciturn autistics use the telephone?

  7. #7 Joe Klar
    Evans GA
    February 24, 2013

    Every hunter knows talking scares away game. It makes sense that men talk less.

  8. #8 David Marjanović
    Museum für Naturkunde, Berlin
    February 25, 2013

    might be explained by increased tendancy towards mild autistic traits in men

    But does that tendency exist? The autism spectrum has long been known to be underdiagnosed in women, because women are already expected to be “modest” and “shy” and stuff; how far does that go?

    How many non-verbal and taciturn autistics use the telephone?

    I know women who aren’t autistic and still avoid telephones whenever they possibly can.

    Every hunter knows talking scares away game. It makes sense that men talk less.

    It would make some degree of sense if they did.

    But they don’t.

  9. #9 David
    February 26, 2013

    “But does that tendency exist?”

    Yes. Mild, sub-clinical autism, is called the Broader Autism Phenotype (BAP). Parents of autistic children score higher than control parents on several measures of sub-clinical autistic traits; see figs 1 & 2 in Wheelwright et al. (2010).

    “The autism spectrum has long been known to be underdiagnosed in women, because women are already expected to be “modest” and “shy” and stuff; how far does that go?”

    Yurkiewicz (2009) acknowledged that mild autism in females is frequently overlooked, he argued that the true M:F ratio maybe closer to 4:1 (for Asperger syndrome), as in severe autism, where symptoms are obvious and hard to overlook. But no one claims parity. Chris Gillberg found, for example, that 23% of females with teenage onset Anorexia Nervosa have a mild ASD; diagnosis of AN often leads to a diagnosis of an ASD (usually Asperger syndrome and PDD-NOS).

    Also, testosterone may explain why more males than females have autism.
    .
    Auyeung et al., 2009. Fetal testosterone and autistic traits. British Journal of Psychology, 100(1), 1–22.

    Wheelwright, S., Auyeung, B., Allison, C. & Baron-Cohen, S. 2010. Defining the broader, medium and narrow autism phenotype among parents using the Autism Spectrum Quotient (AQ). Molecular Autism, 1(1), 10.

    Yurkiewicz I., 2009. Overlooked and Under-diagnosed: Distinct Expression of Asperger’s Syndrome in Females.

  10. #11 Renard Moreau
    renardmoreau.wordpress.com
    February 26, 2013

    [ Smiles ] I certainly learned something new about baby rats.

  11. #12 David Marjanović
    Museum für Naturkunde, Berlin
    February 27, 2013

    Thanks for the refs.