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.

(China Daily 12/15/2006 page4)