Last week saw the third-to-last episode of Fox's sci-fi family drama Fringe. Despite the somewhat wonky fifth season, for me Fringe has represented the best sci-fi offering on network television since Joss Whedon's Dollhouse was cancelled.


For the uninitiated, here's a bit of background (lots more here) required for today's pedantic adventure. Warning if you haven't seen last week's episode: spoilers ahead.


In the year 2167, a Norwegian scientist found that he could genetically enhance the mental abilities of humans, but the increased intelligence came at the loss of certain emotions. Parts of the brain that had once served as the basis for the human emotional experience had been reallocated for logic, reason, and higher thought. Imagine a brain that's mostly prefrontal cortex with an underdeveloped limbic system. The eventual success of the experiment led to the emergence of very smart yet emotionless humans.

These altered humans could not experience happiness, grief, jealousy, or anger. They had no sex drive, and thus could not reproduce. To remedy the problem, the future humans developed a technology that would grow new humans in a sort of hydroponic farm. These individuals were known to the protagonists of the show as The Observers. Thanks to this technology, Observers were typically born as fully mature adults.

Sometime in that future, the Observers made the Earth unlivable, ostensibly due to anthropogenic climate change and pollution. The Observers, aided by technology, decided to solve their problem by traveling back in time to the year 2015, where they could colonize the Earth and prevent the future environmental destruction of the planet. In the year 2036, our heroes are rapidly running out of time to enact The Plan which they hope will finally defeat The Observers and send them back to their own time.

Captain Windmark, chief executive of The Observers, stumbles upon a stereo while hunting down our heroes Peter, Olivia, Walter, and Astrid in an effort to prevent them from carrying out The Plan. He plays the music, cocks his head to the side like a lizard, and listens. The camera cuts to a shot of Windmark tapping his toes in rhythm with the music. Back to Windmark's face, looking vaguely confused.


The inference we are meant to make is this: despite the genetic alterations that gave The Observers their advanced intellect at the expense of their emotions, even Windmark can't escape his humanity. Underneath all the tech and all the genetic engineering, he can still be moved by a piece of music. Maybe, then, he isn't hunting down our heroes solely because it's the rational thing to do. Maybe he hates them. Even The Observers can't outrun their emotions.


Here's the problem. The Observers should not be able to dance.

Dancing, it turns out, is intimately connected to vocal learning. And if The Observers are born as fully mature adults, then for them, language must be innate and unlearned.


In 2009, a group of researchers sifted through hundreds of YouTube videos that claimed to contain evidence of dancing animals, including ferrets, dogs, horses, pigeons, cats, fish, lizards, snakes, owls, camels, chimpanzees, turtles, ducks, hamsters, penguins, and bears. The researchers measured how well the motion of the animals' bodies mirrored the rhythm of the music being placed. At the end of their analysis, the only videos that passed the synchronization test were ones that contained animals who were vocal learners. In all, the researchers found dancing in fourteen species of parrot, and in an Asian elephant. That's not to say that all those other species don't vocalize; of course they do. But their vocalizations are innate, not learned. Just like The Observers.

I'll concede the possibility that The Observers have some sort of Observer School where they rapidly learn language following their "birth," which, technically, would classify them as vocal learners, capable of dancing. But even if that were true, there's more.


Entrainment, or the ability to synchronize one's body movements to an external rhythm, can happen without explicit effort. Living among modern humans during the twenty-one years since The Invasion, Captain Windmark must have encountered some form of "external rhythm," at least once. That he was surprised by his toe-tapping suggests that dancing was a new activity for him. If he was capable of dancing, surely at some point, he would have spontaneously – without explicit planning – bounced his head or tapped his toes in the two decades he spent surrounded by the human culture he was so intent on destroying. In a 2010 paper, psychologists Marcel Zentner and Tuomas Eerola point out, "one of the most curious effects of music is that it compels us to move in synchrony with its beat. This behavior, also referred to as entrainment, includes spontaneous or deliberate finger and foot tapping, head nodding, and body swaying."


In their study, 120 human infants between the ages of 5 months and 2 years were placed on a parent's lap where they listened to a music clip (the parents were given noise cancelling headphones, so they could not accidentally guide the infants' actions). The researchers filmed the infants' movements, and analyzed them, much as the first research group had done with the animal videos.

Zentner and Eerola found that the infants easily entrained their motions to the rhythm of the songs that they heard, whether it was Mozart, a childrens' song, a simple tune, or even just a rhythmic drum solo. They spontaneously modulated their movements according to increases or decreases in tempo.


And the more synchronized they were, the more they displayed "positive affect." In other words, dancing made them happy.

Dancing, or more accurately, rhythmic entrainment, is an unlearned response to an external stimulus that occurs in members of species that have vocal learning, and that – at least among humans – results in increased happiness. This leaves us with three possible reasons that make Windmark's dance entirely impossible, or at least not a reflection of growing emotions.


First, not being a vocal learner, he should not have been able to tap his toes in sync with the song.


Second, even if we granted that Windmark was a vocal learner, capable of dancing, then he should not have been surprised by his toe-tapping, since entrainment is involuntary and he had surely been previously exposed to external rhythms.

Third, even if we granted that The Observers have vocal learning, and that Windmark's confusion can be explained by having never encountered music – not even an errant rhythmic drumbeat during his more than two decades surrounded by human culture – then dancing is still not evidence of emotion. Zentner and Eerola put it this way: "what may have generated positive affect in our infants is the interoceptive feedback from moving in time with rhythmic pulses." In other words, the emotional response was a consequence of dancing; dancing is not, itself, derived from emotion.


This article originally appeared in Scientific American.

Jason G. Goldman is a graduate student in developmental psychology at the University of Southern California, where he studies the evolutionary and developmental origins of the mind in humans and non-human animals. Jason is also an editor at ScienceSeeker and Editor of Open Lab 2010. He lives in Los Angeles, CA. Follow on Google+. Follow on Twitter @jgold85.