Stand up and make a retraction

At last week’s Amaral Lab Meeting—a consistent weekly source of hilarity to rival Two and a Half Men—Adam Pah brought our attention to a retraction notice in the December 19th issue of Nature. Nowadays, any retraction is a notable phenomenon. Plenty of researchers issue corrections to their papers, but it takes a lot for a paper to be outright retracted. And a retraction occurring in one of the most prestigious journals out there is indeed rare. But what made this retraction especially notable was the title of the paper: “Dance reveals symmetry especially in young men.” Obviously, we had a lot of questions, including “Seriously?” and “This was a paper?” and “In Nature?” and “What the?”

What’s particularly strange about this retraction is that the authors give no reason for it. The retraction statement is two sentences, one of which details their results, which is completely irrelevant since those are now retracted. Anyway, I decided to make it my goal for the day to read “Dance reveals symmetry especially in young men” and attempt to determine why it was retracted, while ridiculing the paper and its authors along the way. After all, there’s less fear of retribution from mocking a retracted paper than a still-active one (not that that’s stopped me before).

Here is the first sentence of the paper’s abstract:

Dance is believed to be important in the courtship of a variety of species, including humans, but nothing is known about what dance reveals about the underlying phenotypic—or genotypic—quality of the dancer.

Oh boy, we’re in for a treat. From the entire concept to the phrase “including humans”, this paper should be a riot. Full credit to the authors William M. Brown, Lee Cronk, Keith Grochow, Amy Jacobson, C. Karen Liu, Zoran Popovic, and Robert Trivers for getting this paper into Nature and for very likely creating a voodoo doll of Philip Campbell. The majority of the authors are from Rutgers University, making the retraction of this paper the biggest scandal to hit Rutgers since 2:30pm.

I should also mention that this paper was originally published in December 2005. That means
that for eight full years, this was science.

One measure of quality in evolutionary studies is the degree of bodily symmetry (fluctuating asymmetry, FA), because it measures developmental stability.

Source: The Dark Knight, because Harvey Dent was really unstable after the accident.

Motion-capture cameras created controlled stimuli (in the form of videos) that isolated dance movements from all other aspects of visual appearance (including FA), and the same population evaluated these videos for dancing ability.

What’s with all the parenthetical asides in this paper? I’m half-expecting to see “(such as seals)” appear in here somewhere.

Darwin was the first to suggest that dance is a sexually selected courtship signal.

That was a hilarious bit in Darwin’s HBO Comedy Special, “The Origin of Feces”.

Across diverse taxa, increased FA is associated with increased morbidity, mortality, poor fecundity and other variables linked to natural and sexual selection.

Halitosis. Back hair. Enjoyment of anime. Liking CBS sitcoms. Majoring in materials science.

There are no studies in humans (or any other species) linking variation in dance quality with genetic and/or phenotypic quality.

And now, there are again none.

Motion-capturing of 183 human dancers was conducted in 2004 in Southfield, Jamaica.

Researchers confirmed to be completely stoned during the entire project.

Each individual danced alone to the same song (popular at the time in Jamaican youth culture)

Hoobastank, got it.

Forty dance animations were chosen on the basis of the level of fluctuating asymmetry of the dancer, using two measures of FA over time (1996 and 2002). Specifically, individuals in the top third on both FA measures were categorized ‘asymmetrical’ (n = 20), while individuals in the bottom third of both samples were categorized ‘symmetrical’ (n = 20).

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This experimental strategy helped to control for longitudinal changes in FA due to the accumulation of developmental errors, compensatory growth or measurement error.

Then the paper goes into some stuff about what they predicted and how their results perfectly match those predictions. Lucky them.

We do not know what mediates the associations reported—perhaps asymmetry itself or a covarying characteristic such as neuromuscular coordination or health, including freedom from parasites.

Does dance ability correlate with reproductive success?

“Fred Astaire had two kids, so our study is inconclusive.”

We plan to address this question with long-term data from the same population.

In the meantime, we’ll need to spend the next several years in Jamaica, so hold all our calls.

The fact that the authors (or all but one of them, as Keith Grochow “could not be contacted”) don’t provide a reason for the retraction of their paper is somewhat troubling. We don’t know if there was a problem with their methods (which were questionable) or their statistical analysis (which was convenient) or something else entirely. Without knowing the motivation for the retraction, other scientists could conceivably make the same mistakes in the future. That is, assuming any other research group has the wacky desire to investigate a connection between dance and body symmetry again. (Hey, it’ll get you published in Nature.) Nevertheless, the researchers terse retraction statement is not a desirable trend. More than likely, the authors decided to take another cue from Jamaican music and adopt the Shaggy defense: “It Wasn’t Me.”