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Odontocetes are whales that have teeth in their mouths. There
are about 73 species of odontocetes, including dolphins
and porpoises. Toothed whales are different from baleen
whales in several ways. Besides having teeth, they have
only one opening at their blowhole, tend to swim faster, and
usually have a dorsal fin. Most toothed whales are smaller
than baleen whales, but range in size from the 5-foot vaquita
(a type of porpoise) to the 60-foot sperm
whale. Toothed whales also tend to be more social than
baleen whales, often living and hunting in groups.
Like bats, toothed whales use echolocation or sonar to detect
objects in their environment, such as their prey. They produce
sounds which are directed through a fatty organ, called a
melon, on the front of their head. The sounds bounce off solid
objects and return to the animal through their hollow lower
jaw (like an echo), so the animals are able to get a "picture"
of what is around them. Most species of toothed whales also
use sound to communicate with each other. Many species, such
as the sperm
whale, seem to have individually identifiable calls. Orcas
or killer whales live in groups or pods, and some pods have
a dialect or accent, just like we have accents depending upon
which part of the world we are from.
While most toothed whales have a mouth full of teeth, there
are some unusual exceptions. Sperm whales only have teeth
in the narrow lower jaw, and strap-toothed whales have only
two lower teeth which wrap around the top of their jaws so
they cannot fully open their mouths. The two teeth of many
species of beaked whales may only erupt in males, so there
are actually toothed whales with no functional teeth at all.
Scientists are still trying to figure out how these whales
catch and eat their prey. Some think they use a "sonic
boom" to stun their prey, then use suction to eat them
whole.
There is much more to discover about the odontocetes. For
example, beaked whales spend most of their time in the deep
water, far from shore, so they are rarely encountered. Even
now, new species are still being discovered. If we are to
keep learning about these rare creatures, it's important to
protect them and their ocean home.
Learn more about the following:
Baleen whales
Dolphins
and porpoises
Orca/killer
whale
Sperm whale
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Odontocetes-Toothed
Whales 