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Re: beaks and teeth
On Wed, 3 Feb 1999, Thomas R. Holtz, Jr. wrote:
> At 10:46 AM 2/3/99 -0500, Patrick Norton wrote:
> >A few questions about beaks and teeth:
> An important question here: by "beak" do you mean "rhamphotheca" (a
> cornified structure) or do you simply mean "a toothless part of the snout"?
> >1) Except for dinosaurs, including some Tertiary birds,
> No known Tertiary bird had teeth. Some had "pseudo-teeth" (serrated edges
> to their beaks), but all birds with actual teeth died out at or before the
> K-T boundary.
Wasn't there an report a while back about producing teeth in chickens?
This would mean the genes for this lasted all that time. I suppose they
could have lain dormant in birds for millions of years, but I wonder if
they didn't get expressed now and then.