蜈蚣真的有一百只脚吗？
[ 2007-02-05 13:54 ]
人们常把蜈蚣叫做百足虫，在英语中它的名字centipede就是“有100条腿”的意思。那么，蜈蚣真的有那么多条腿吗？这可不一定哦！
 Scientists, whether intentionally, or
unintentionally, tripped us up when they named the centipede, one of the oldest
creatures in existence.
Yes, centipede really does mean "100-footed," and yes, some centipedes
actually do have 100 feet, but no, not all do. In fact, some centipedes have
more than 100 feet, and some have as few as 30. Perhaps, mathematicians, not
scientists, should have done the calculations, and should have named this member
of the species "Myriapoda," Latin for 'many footed'. Yes, the millipede also
belongs to this ancient species, but does it really have 1,000 feet, as its name
implies? Doubtful.
The centipede emerges from eggs, laid in the open, with either a full set of
legs, or with a starter set of seven pairs, and plays add-a-pair each time it
sheds its skin, until it reaches maturity. These paired legs grow out of a
segment of the centipede's flat, many jointed body, making them much easier to
keep track of, and the centipede less likely to stumble as he forages for food
by night. The sheer number of legs, however, may present a problem for the
centipede by day, as it must safely tuck them in, when taking cover under rocks
or rotting wood.
The 8 to 10 tropical varieties of centipede have little to fear in this
regard, because this kind of centipede bears enough poison in its two claws to
kill a small bird. The claws containing the poison, as with all other
centipedes, are located, along with its two feelers, on the section next to the
head.
（英语点津 Annabel 编辑）
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