There are thousand of pigeons in any big city in the world. (1) __________________________________? Just how pigeons find their way home is a bit of mystery. Some people think that they use landmarks that is the pigeon knows what the land is like from the air and it uses this like a map. (2) _______________________________________, which can easily be seen from a long way off. Other possibilities are that pigeon use the position of the sun to work out directions or that they have some kind of built in compass. (3) ____________________________________ but they still aren't to sure how pigeons find their way home. It seems likely however that pigeons like airline pilot use a number of different methods to guide them on their long distance journeys. Perhaps, one day we'll learn their secret.
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作者: susan.sui 时间: 2014-6-20 14:06
but do you know that this common bird is able to find its way home from even hundreds of kilometers away
a landmark in Sydney for example is the opera house
for quite a few years now ,scientists have been carrying our experiments on homing pigeons
