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.
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
发表于 2014-6-19 14:29
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发表于 2014-6-20 14:06
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