Page 30 - It Can't Be True! Animals! - Unbelievable Facts About Amazing Animals (DK)
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How do
whales sleep?
Most whales, like other mammals, This upright
position is
sleep horizontally. However, the still a mystery
to scientists
sperm whale is an exception: researching the
sperm whale’s
this supersize snoozer sleeps sleep habits.
upright underwater.
These mighty mammals take power
naps lasting no more than 15 minutes,
while floating upright below the ocean
surface. Sperm whales spend only
7 per cent of their lives asleep, a tiny
amount compared to humans who spend
nearly 33 per cent of their lives asleep. Sperm whales close
their eyes and remain
entirely motionless
SKY-HIGH SLEEP while sleeping.
Some birds can sleep during
flight by keeping one eye open
and half their brain awake.
The Alpine swift adopts this
method to stay airborne for
up to 200 days at a time.
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