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Re: dinosaur tongues and the Jacobson's organ, 'jamolnar@juno.com' wrote...

> But that brings up another point: what about evidence for dinosaur
> tongues?  If they had jacobson's organs like monitor lizards, they should
> have forked tongues.  But if most dinosaurs were more along the avian
> line, they should have very simple, pointed or blunt-end tongues.  Any
> evidence either way?

No archosaur has a jacobson's organ - it is primitive for amniotes and has been
lost in several groups including some mammals, turtles and archosaurs. No
dinosaur would therefore have a forked tongue - this is highly unlikely anyway
as it is a synapomorphy of autarchoglossan lepidosaurs (best developed in
platynotans like varanids and snakes) and requires a twin-pocketed jacobson's
organ into which the two branches of a bifid tongue fit. 

The extant phylogenetic bracket (EPB) for dinosaurs indicates that they had
relatively mobile, muscular tongues as both crocodiles and primitive birds do.
Contrary to some oft-reproduced dogma, crocodiles do in fact have a mobile
tongue that can be lifted from the floor of the mouth. It can't be protruded
beyond the jaws though. Crocs have blunt-tipped tongues but I can't say I've
ever seen a ratite tongue - pointed or blunt tip? Of course, some herbivorous
dinosaurs (derived ornithopods in particular) are so unlike crocs or basal birds
in cranial anatomy they may well have departed somewhat from the primitive
archosaur plan. Comments anyone?


It's interesting that _Titanus_ may have survived almost into modern times. The
Yakama indians have legends of the 'Pach-an-a-ho' ('Crooked beak/Rough-looking
bird'): a giant brown (apparently flightless) bird. One problem: these legends
originate from the Mount Adams area... as if the sasquatch and weird UFOs there
weren't enough. 

"They might be thought of as walking Swiss Army knives, having the tools to deal
flexibly with a variety of feeding situations"