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Birds of a feather not behaving together
By Zou Hanru
I often see a pair of Mynah
birds on the roof of a neighbouring building. Hong Kong is one of the
few great metropolises in the world where you can walk for less than
half an hour from a bustling and congested business or shopping district
to escape to the wild. These Mynah birds, I guess, need less than a
couple of minutes to do so.
As a child, I was told Mynah birds were good singers and very good at
mimicking human speech. No wonder I still see people in this most modern
of cities carrying their beloved pet Mynah birds in wooden cages on
their daily walks. A large majority of these bird lovers are on the
wrong side of 50, or even older.
I’m not sure whether I always see the same pair of Mynah birds on that
roof, for I’m no ornithologist not even an avid bird-watcher. But I am
sure I have never heard them sing. The only thing they do is peck on the
roof for worms, or maybe insects, walk in their typical “gait” and fly
away.
They certainly do communicate with each other through what sounds to me
like squeaks and, at times, whistles. I wish I could understand their
language, or the difference between their guttural and other squeaks and
those of their forest-dwelling cousins.
The reason I am saying this is that a recent in-depth study found that
“birds living in cities are performing a type of ‘avian rap’ while their
rural counterparts are sticking to more traditional sounds.”
A team of dedicated Dutch researchers studied a wide variety of birds,
reaching the conclusion that the “urban species sing short, fast songs
rather than the slower melodies of countryside birds.” City birds sing
at a higher pitch, too, and are not averse to trying out different song
types.
This may not be music to a lot of initiated ears. But I, for one, am not
sure whether this is what evolution is all about, or whether homo
sapiens have been forcing all the other species on Earth to change their
habits, and perhaps evolve differently.
As far as I understand, evolution means a total transformation in shape,
size, appearance, food and other habits, and in the type and pitch of
sound we make. In short, it denotes complete physical and chemical
change.
What has been happening to city birds is different they look the same,
behave the same, have the same food and foraging habits but use
different pitches, songs and styles of communication to attract mates.
Let’s see what the experts say: “City birds have adapted to counter
background noise and increase their chances of finding a mate.” So it’s
not evolution in the true sense of the term, after all.
The researchers focused on Great Tits in 10 major European cities
including London, Paris, Amsterdam and Prague, and compared them to
their forest-dwelling cousins. In every study, city birds were found to
sing a more varied array of songs: Short and with higher minimum
frequencies. The urban Great Tits experimented with one- to five-note
calls. But the forest-dwelling Great Tits stuck to more normal
combinations of two-, three- and four-note tunes. One Rotterdam Great
Tit was even found attempting a 16-note song, possibly copied from a
Blue Tit. Though I hope researchers would try to find out how birds that
travel between forests and cities almost every day like they do in Hong
Kong have adapted to the changing environs, I know this would be a far
more difficult project to handle.
But the University of Leiden’s study has taught me one thing. All the
animals and birds around us are changing to suit our needs, to adapt to
the environment that we’ve built. They don’t want to change our habits,
our needs and our environment. But we human beings are not ready to even
give an inch of space to the flora and fauna of the Earth and we are
doing so at our own peril.
—The Daily Mail-China Daily news exchange item |