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NARWHALS?



With regard to the question "How do animals with forward-pointing teeth get the
fish off their teeth and toward their gullet?", Garrison Hilliard says..

> Large fishi-eating animals with forward pointing teeth... narwhals.

Err.. it's fairly well established that narwhals do _not_ use their incredible
teeth (=tusks) for catching fish! I should say incredible *tooth* as,
ordinarily, only a single tooth is sported, and by the male (I think it's a left
incisor). Other teeth are not typically emergent, but in rare cases a male may
have two tusks, and sometimes females (normally without any emergent teeth) have
one or two tusks. I am not aware of small (=non-tusk) emergent teeth in the jaws
of any recorded narwhal (they would seem likely, given their occurrence in other
normally edentulous cetaceans), but apparent narwhal x beluga hybrids have them.
Despite suggestions that the tusk is used as a sonar-emitting device to stun
fish or 'shout' at rivals, field observations and tusk damage show pretty
convincingly that it is a weapon with which males spar. It may lack an otherwise
'functional' purpose. I wonder if the same goes for _Odobenocetops_. As for
walruses...

To return to the fishing pterosaurs etc. though, note how a number of
piscivorous birds, including herons and anhingas, actually spear a fish right
through its body. As I understand it, both groups actually jab with their beak
open, so they are making a strike with two deadly points rather than one. A
speared fish is then flipped into the mouth (though I have seen egrets put the
prey on the ground and hold if down with a foot while pulling their head back,
they then pick the fish up). I don't see why the same thing can't work for, say,
a fishing rhamphorynch that spears a fish on its pointy front teeth.

"I am the last one!"

DARREN NAISH