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HOW DO FI SH
LIVE IN WATER?
You must have seen how fast and brisk fish are in water. In order
to swim, a fish does not need to make any movement other than
to flap its tail from side to side. This ease of movement that
fish have in water is a result of their flexible backbones as
well as some systems in their bodies.
A fish expends a large amount of energy while swim-
ming. This is not because it swims fast for long
times. Fish need considerable amounts of energy in
order to reach high speeds from being stationary.
It is vital for a fish to gain speed instanta-
neously because it needs to do so in order
to escape from predators.
Moreover, fish move against the current
most of the time. Consider how hard it is for
you to move in water and how easy it is to
move while you are walking on the street.
Compare living underwater and living
on the face of earth.
W O N D E R F U L C R E A T U R E S
