Snowball, the Dancing Bird

A video of a dancing bird has become the latest YouTube sensation. Some people thought the bird's performance was faked, but for me, it is not surprising, given the sophisticated ability birds demonstrate for manipulating pitch and rhythm in their songs, that a bird shows the ability to keep time with music. Neuroscientists, including John Iversen of the Neurosciences Institute, have studied the dancing bird and confirm it is capable of extracting a beat from sound.



What impressed me most about Snowball's performance is when he lifts his leg and gives it a little shake before bringing it down. As the investigators mention, it may be prompted by the pace being too fast to put his foot all the way down in time with the faster beat, but it piques my curiosity further. It appears Snowball is dividing the beat when he waves his foot, into two or three little waves, which if I am seeing it correctly, suggests birds are capable of division of the beat and perceiving and manipulating a metrical framework. This is simply astonishing were it be to true, but perhaps not unexpected given the sophistication of bird vocalization and communication. It is one thing for a bird to keep time with a beat and an entirely different for a bird to exhibit division of the beat.

When people sing (or compose a melody to sing) the tones are not of arbitrary duration. No one could sing a song consisting of a series of tones of arbitrary duration measured to fractions of a second. Could you imagine signing a melody: A 1000ms, F 1500ms, E 500ms, D 1000ms, A 1000ms? The human mind is not well suited for measuring duration in milliseconds on an ordinary basis (we can leave out extraordinary abilities some humans may possess or develop). What if someone asked you to pick up the pace to sign faster? Each duration would have to be recalculated down to the millisecond, in your head. For this reason, music is organized by relative measures of duration.

In reality, when people sing or play music, they use simple division of the beat to measure duration. This is usually achieved through the division of a steady beat by whole fractions, usually simple divisors, like two or three. The most basic division of the beat is by two. When a tone of shorter duration than the beat is required, the melody will use a tone one half of the beat, or one quarter or one eighth and so on, down to the ability of humans to resolve divisions of time. The other main division of the beat observed in music is by three. So for every beat you have the possibility of three tones, six tones, twelve tones and so on. The human ability for perceiving and manipulation this time structure is sophisticated. Musicians can anticipate the division of future beats, playing notes that persist across multiple divisions of the beat or create "holes" or silences for certain beats, playing with the listeners expectations (this is called syncopation). I have to wonder if the small movements he makes dividing the beat follow any ornamentation of percussion or melody in the song. In the background, another bird can be seen bobbing his head to the beat, in a clear parallel to human "head banging."

Although I would have to watch a lot more video to be sure, what I have seen suggests he may be dividing the beat and deserves further investigation. I would not be surprised to find that birds do erect a sense of metrical time in sound and can mentally divide the beat and even anticipate it, perhaps even perceive syncopation. It is fascinating to watch Snowball lose and pick up the beat again.

I did watch a couple of video clips. At about 2:00 into the following video he lifts his foot and waves time to the beat, but does not divide it.
(http://www.youtube.com/watch?v=N7IZmRnAo6s)


In the following video, notice how he keeps the beat when Stevie Nicks sings "ooh, ooh" on the beat? This suggests he has an expectation of the beat even when the beat is not marked by a percussive instrument. At about 1:05 he may have divided the beat with a wave. He does lose the beat more frequently when based only on Nick's vocals or less percussive sections. At 2:31 he appears to divide the beat with a wave again. And at 2:56. I'm not sure if he's just losing the beat or dividing it...but this is a seriously important question about the intelligence of birds. At 4:43 also.
(http://www.youtube.com/watch?v=GYMBIGTteWA&feature=channel)

(Note: The time required for a complete cycle of A above middle C is 2.27 milliseconds and a sixteenth note at a metronomic pace of 60 clicks per second is 250 milliseconds, according to Wikipedia http://en.wikipedia.org/wiki/Millisecond 2009)