Whales are pretty amazing. Whales are mammals
like us, so they can’t breathe underwater.
They can hold their breath a lot longer than we
can, but still need to come up for air.
Blowholes are actually nostrils on the top
of their heads. The ancestors of whales were
land mammals that had nostrils more like a dog’s.
As generations of these animals spent more time in
water, those that happened to have higher nostrils
were probably more likely to survive and leave
offspring. You can actually see on a whale’s
skull how all of the bones of their skulls have
shifted to move the nostrils up. Lots of
animals that live in water have nostrils that are
high on their heads. Beavers and alligators are
examples. This is an example of how the function
of a structure depends on its form or structure.
Because their nostrils are on the top of their
head, whales can breathe without getting out of
the water. It’s almost like a snorkel. Whales can
blow water out while they are still a bit
underwater by using a lot of pressure. To inhale,
the nostrils have to be a bit above the water, but
the rest of the whale can stay underwater. This
takes a lot less energy than lifting the entire
head out of the water and it may be safer.
They can also close their blowholes to keep water
So you can see that a whale without a blowhole
would have a big problem. Without blowholes,
they’d have to lift their entire heads to breathe
through their mouths.
What other ways are whales adapted for life in the
Thanks for asking.