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When's the last time you
saw a beaked whale? Despite the fact that they look a little bit like
bottle nosed dolphins, it's actually likely that you've never seen one!
An article on the discovery of the remains of a pair of spade-toothed
whales caught my interest and I decided to do a little research. With
only two full specimen discoveries in over 140 years, spade-toothed whales
might just be the rarest of whale species.
Beaked Whales
Beaked whales are a little-known group of whales that are excellent divers,
staying below the surface for 20 minutes or more. About 21 species of
beaked whales have been identified. Click here to read more about them.
Spade-Toothed Whales

The spade-toothed whale is
the rarest of all beaked whale species. It was named after the discovery
of a jawbone off the coast of New Zealand in the 19th century. Later, a
few skulls lacking mandibles were found. The few whole specimens that
were found were often misidentified as other beaked species such as Gray's
beaked whale. Further analysis helped determine that spade-toothed whales
are genetically different.
Most beaked whales are
differentiated by the shape and number of teeth for two reasons:
- The
external characteristics of beaked whales are quite similar
- Most
specimens that are discovered have died upon being beached; physical markings
like stripes on the face may disappear after some time
The reliance on teeth is
not always very accurate because the teeth may not yet have erupted in
juveniles and in some species, never erupt in females. The spade-toothed
whale got its name for its 9 inch long teeth which are wider than those of
other beaked whales. The shape of a tooth is similar to a flensing spade.
And what is a flensing spade, you may ask? That's where things get
a little grim. A flensing spade was used by whalers to remove blubber
from the carcasses.
As there were only two known full specimens of the spade-toothed whale, further
information on the physical description of these animals isn't known for sure.
The female discovered off the coast of New Zealand in 2010 was 5.3 meters
long, while her calf was 3.5 meters.
All of the partial and whole specimen discoveries have been made in the South
Pacific. No live spade-toothed whale sightings have been confirmed.
After The Discovery - What Comes Next
The findings of the study
emphasize the importance of reliance on genetic material to identify species.
Positive confirmation of a species by its DNA can help establish more
reliable physical criteria for identification.
So while you may not see a
spade-toothed whale (or any beaked whale, for that matter) on your next whale
watch, keep your eyes peeled. You never know!
References
http://en.wikipedia.org/wiki/Flensing
http://en.wikipedia.org/wiki/Spade-toothed_whale
http://download.cell.com/current-biology/pdf/PIIS0960982212010597.pdf?intermediate=true (image credit)
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