Ha, ha... I am sitting here with a margarita, so maybe I shouldn't laugh.So here I am trying to read the article after a bit of wine and I'm stuck on the loss of enamel. It seems to me the composition of beak is still different than teeth even with that loss. Again...I've had wine so my comprehension is a little...less...
Beaks are made of keratin, like your fingernails. Beaks are probably modified scales, as are claws.