Ⅱ 英文を読み、下記の問いに答えなさい。
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Like a tiny submarine, the chambered nautilus speeds through the
ocean on little jets that it creates by sucking in water and spitting it
out.
However, as ways of movement go, jet propulsion is not usually a
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very good use of energy. In the ocean's depths where oxygen gets
thin, the nautilus seems to be putting itself at risk by expending so
much effort on movement. Fish use far less energy by pushing at
the water with their fins. So how does it manage to jet around
unscathed in the ocean's depths?
Graham Askew, a biomechanics professor at the University of Leeds,
set out with a graduate student, Thomas Neil, to understand better
how this shellfish moves. They found that the nautilus is actually a
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highly efficient jet-propelled creature, wasting much less energy than
