in This is Your Brain on Music).
Darwin devoted ten pages to birdsong and six to human music in
The Descent of Man, noting that both have their origins in sexual
selection, the desire to attract mates. As usual, he was correct. The
Brits love birds so much that BBC radio broadcasts a daily ninety-
second spot of birdsong. British Petroleum gas stations recently began
playing birdsong in the bathrooms. “The aim was to create a mental
connection with freshness,” said a newspaper report. Good luck with
that.
There appears to be something to the “freshness” idea. As British
acoustics consultant Julian Treasure put it, birds sing in the morning,
and we associate the sound with alertness and safety, a day when all is
right with the world. This is how we’ve heard birdsong throughout our
evolution. It’s when you don’t hear the birds that something is wrong.
Also, birdsong is stochastic, random and nonrepeating, so our brains
interpret it not as a language but as a kind of background soundtrack.
In fact, birdsong has some uncanny similarities to human-made
music, and its range and technical wizardry might, on some
unconscious level, stimulate our happy-music neurons. The French
avant-garde composer Olivier Messiaen incorporated birdsong into
his works and said of birds: “They are our desire for light, for stars,
for rainbows, and for jubilant song.”
The brown thrasher can sing 2,000 songs. The cowbird has 40
different notes, and a horny chaffinch might sing half a million times
in a season. The Australian lyrebird is the world’s best mimic, and
can imitate chainsaws, car alarms and the click of a camera shutter
(none of which reflects well on its habitat). The melodic hermit
thrush most often sings on a mathematic substrate that follows
harmonic intervals in recognizable pitches. The researcher who
discovered this is named—I kid you not—Emily Doolittle, a
composer at Cornish College of the Arts in Seattle.
Despite the 300 million years that have passed since birds and