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我听着舌头比之前软点了…………大家给给意见吧·~~~~~~~
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文章：小马分类上，动物学第三篇-------乌鸦
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You know, it's kind of fashionable among students of birds to study well and exhausted species, especially in danger ones like golden eagle and4 b- `! ?1 y6 M9 }
spotted) @2 B' l+ K4 j/ C3 l! l' V4 X7 |
owls. But I often think that everyday-birds, birds that really are part of our lives,
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9 ]7 }+ ^ b! M: l, }So I’d like to spend some time talking about a very common bird----black crows. It might surprise
, }' W, u' }# [4 U( u* Z7 Q& eyou to know that crows are among the most challenging birds to observe and study. First of all, they look alike, picking out one of several individual crows in a flock and finding them again later is almost impossible. People study in large animals can put some kind of marker on them, so they can tell them apart. Well, you can trap a large animal like a bear
7 s3 k# n6 s/ i1 Nin a mobilized or a tranquilized gun. Then it’s easy to put a tag on it. But try doing that to a crow, you probably kill it. Secondly, crows are highly intelligent survivors. They adapt easily to wildly varying situations. This adds to the difficulty of studying in them, because they pick up so many individual allies
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applies to the whole species or just the particular crows you've been watching, one general observation about crows that can’t be made the reasonable degree of certainty is that in the last 40 years, more and more crows have been found living in large cities. They are attracted by people, who produce a normal surmount) C+ O/ m) S7 P, @) [7 x
of garbage and leave them places that crows can easily get to. It makes$ }) \$ [ A$ ^$ ^" S) q8 k
for? distances they must travel to hunt a lot shorter
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本帖最后由 棉花糖落落 于 2008-7-25 11:30 编辑 ]
