佐々木：つかぬことを伺いますが、鳥にも方言があるんですか。
鳥類学者：ええ、ありますよ。中には、70もの方言を使える渡り鳥もいるんですよ。
Tsukanu koto
Sasaki: Tsukanu koto wo ukagaimasu ga, tori ni mo hoogen ga arundesuka.
Choorui-gakusha: Ee, arimasu yo. Naka ni wa nana-juu mono hoogen wo tsukaeru watari-dori mo irun desu yo.
Sasaki: Excuse me for changing the subject, but do birds also have different dialects? Ornithologist: Yes, absolutely. There are some migratory birds that can use as many as 70 dialects.
The expression tsukanu koto is used to introduce a question that doesn't follow on from the preceding conversation. Tsukanu is a shortened form of tsuzukanu, or in other words, a negative of the verb tsuzuku, meaning to follow on.
The conversation above took place when I met the renowned ornithologist, Mr. A. People tend to assume that ornithologists spend most of their time outside watching birds. In fact though, he spends most of his time working in a study tracing the movements of birds on his computer. I'm sure the birds don't imagine for a minute that their whereabouts are being monitored by a bird expert In reply to my question above, the ornithologist made some interesting points. He told me that birds can produce an enormous variety of songs, and that rather than any innate skill that they are born with, this is something that they acquire as they grow up, learning from their parents and the other birds around them. In fact, he said, if you take one bird and keep it on its own, it cannot produce the same song as the other birds around it.
The wild duck, for instance, apparently learns to quack between four weeks and 100 days after being born. During that period, if the bird is kept in isolation, it will not learn to quack.
Next, he turned to me and said, Watashi mo tsukanu koto wo o-tazune shimasu ga, sensei no go-senmon wa nan deshitakke (Sony if this is moving away from the point again, but what did you say you specialized in?) Language studies happens to be my specialized field - something which the present subject has a lot in common with.
The rate at which children learn languages up to their fourth year in elementary school, about the age of nine, is extremely fast, but after that the learning rate starts to tail off.
Native Japanese speakers learn almost all the grammatical structures and sentence patterns of Japanese they need by around that age. When it comes to learning a foreign language, however, other aspects come into play, making it quite a different matter. I thought how interesting it was to see certain connections between the way birds learn to sing and the way human beings learn to
speak.