Whales and
dolphins have
bodies which are well adapted to a life in
water.
But their bodies differ from
fish and other water animals - they
still carry some rudimentary organs from their past as land animals,
and their skeletons and inner organs are much more similar to those of
land
animals than the organs and skeletons of fish.
Probably the
most obvious difference between whales and fish is that fish can live
under the water their entire life, because they have gills, while
whales, having been land animals, have lungs
and need to go to the
water surface regularly to breathe in oxygen from the air.
Whale
Skeletons
Poster by AllPosters.
Click on thumbnail to
buy
Whale skeletons have
a long vertebrae
(back-bone) like all vertebrate animals, including
fish. But unlike fish, they have large ribs
around their lungs, and the
bones inside their flippers have five fingers
exactly as
do human
hands. While the bones of land animals are strong because they have to
carry the animal's weight, the bones of whales have become soft because
in the water, much of the weight is carried by buoyancy. When large
whales
accidentally get out of water, their inner organs can be crushed by
their
own weight because the bones are too soft to carry the weight.
Inner
Organs
Poster by AllPosters.
Click on thumbnail to buy
Inner whale anatomy is similar to the anatomy of land mammals
(there are even rudimentary remains of back legs inside whales'
bodies). And the organs are huge. A large baleen whale's heart is as
large as
a small car. Whales' lungs
are huge, to enable the animal to spend
extensive time under the water. They have,
however, ears
that are adapted to water. Instead of an outer and inner
ear like in land animals, whales' throat acts as the outer ear, since
under the water there is not much difference between the outer and
inner environment.
Outer
Body
Parts
Poster by AllPosters.
Click on thumbnail to
buy
Whales'
outer body parts are more similar to water than land animals. Their
front legs evolved to flippers
and their tails
are similar to fish
tails, except that fish tails move horizontally while whale tails move
vertically. It consists of two flukes,
which, as opposed to the
flippers have no bones in them. Many, but not all whales also have a
dorsal fin
(others may have a hump). In some species such as killer whales the fin
is quite
distinctive, in others such as beluga,
narwhal, bowhead
and right
whales, it is absent. Other distinctive features are blowholes - of
which toothed whales have one and baleen whales have two. Those
basically work as nostrils to breath, and they are on the top of their
head, which allows them to be mostly under water while
breathing.
Disclaimer: Although
best efforts have been made to
ensure
that all the information on this
site is correct,
whale-and-dolphin-facts.com
is
not to
be blamed should
there be a mistake.
Copyright notice:
All contents of this website are strictly protected by the Law of
Copyright.
Copyright
2010-2014 whale-and-dolphin-facts.com. ALL RIGHTS
RESERVED.
