When a bird changes its song . . .

When a bird changes its song . . .

Guest Essay by Kip Hansen – 24 July 2020

featured_imagefeatured_imageI like birds – big birds, small birds, common birds, rare birds – all kinds of birds.  I have fed them in my backyard for years and watched then wherever my travels have taken me.  I am not your typical birder – I just find birds interesting.

This story offers a break – albeit a short one — from  the noise and tumult of the various popular delusions  that are currently circulating and stirring up the feeble-minded and faint-of-heart among the general public:  Covid Madness, Climate Change Madness, BLM Madness, Cancel Culture Madness, Trump Derangement Madness – to mention a few.

Please note that there is nothing important about this story.   There is no scientific breakthrough.  But it is interesting on a couple of intellectual fronts.

Here’s the headline from Popular Science:

“White-throated sparrows are ditching their classic song for a new tune

The birds are abandoning their old song with unprecedented speed”

A brief synopsis from the PopSci piece:

“When ornithologist Ken Otter moved to Prince George in northern British Columbia in 1999, he soon noticed that there was something odd about one of the songs the birds in his new home were singing.

Otter was used to hearing male white-throated sparrows, which are common across much of North America, whistling a tune that ends with a repeating set of three notes, known as a triplet. But when he and his colleague Scott Ramsay, now at Wilfrid Laurier University in Ontario, listened carefully to recordings of the sparrows in Otter’s new home, they couldn’t identify the musical trio. They quickly realized that the birds were singing a different variant of the song that ended in a set of two notes called a doublet.

Otter, Ramsay, and their colleagues have been tracking this new dialect over two decades. During this time, it has swept across the continent and begun to replace the old triplet-driven version of the sparrow’s song. This appears to be the fastest documented case where a new dialect has caught on and spread to birds far and wide, the team reported [link is a .pdf] on July 2 in the journal Current Biology.

sparrowsparrowSo, for “unprecedented speed”, read 70 years, maybe more (see more on the time period below).

Yes, these audio-orthinologists have actually followed this changing bird song for over 20 years, and have finally turned in their report.  Not only have they followed this changing song, but they have tracked which birds are singing it and where they might be passing it along – a sort of bird-song epidemiology.  They report:  [link to report .pdf]

“In Brief:

Otter et al. study the cultural evolution of song variants in white-throated sparrows. Using songs of nearly 1,800 males recorded between 2000 and 2019, Otter et al. show the progressive adoption of one song variant (doublet-ending song) by males starting in western Canada and sweeping over 3,000 km eastward to replace the traditional triplet-ending songs.

And summarized as:

“White-throated sparrows, Zonotrichia albicolis, for example, traditionally sing a whistled song terminating in a repeated triplet of notes, which was the ubiquitous variant in surveys across Canada in the 1960s. However, doublet-ending songs emerged and replaced triplet-ending songs west of the Rocky Mountains sometime between 1960 and 2000 and appeared just east of the Rockies in the 2000s. From recordings collected over two decades across North America, we show that doublet-ending song has now spread at a continental scale. Using geolocator tracking, we confirm that birds from western Canada, where doublet-ending songs originated, overwinter with birds from central Canada, where the song initially spread. This suggests a potential mechanism for spread through song tutoring on wintering grounds.”

Fascinating.  Fascinating that anyone cares enough about the male mating song of the white-throated sparrow to study it for 20 years over both a 70-year time span and a over a continental-scale geographical area.   Regardless of one’s opinion on the value to human society of such an endeavor,  that is scientific dedication.

The New York Times covered the story as well, and offered audio clips for the two song variants.  You can play them in the Times web page linked or download/listen to them here as .wav files:  Triplet-ending Song and Doublet-ending Song.

We now return you  to your regular programming covering  The Madness of Crowds.

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Author’s Comment:

In spite of the odd behavior of the humans, Nature just keeps rolling along.  Birth and death, evolving behaviors, landscapes change from forests to meadows to grasslands and back again,  and all without requiring permission from the silly humans who far too often believe they are in charge of everything.

When it all seems just too much, I suggest getting out and sleeping under the open sky watching stars slowly move across the heavens.  I did so last night – as always, very mentally and spiritually refreshing.

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July 24, 2020 at 12:58PM

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