RE: pineal gland

["Cunningham, Betty" <Cunningham@sega.com>]

Mickey wrote: (hi  Mickey)
>  Pineal glands are used by mammals to determine
>photoperiods in order to lock their reproductive cycles into the
>seasons of the year.  I think I expressed this reservation when Betty
>first brought the subject up two years ago -- I'm not sure it makes a
>lot of sense to talk of pineal glands that aren't fully functional.

 perhaps I mean an animal dependant on the pineal gland to control it's   
breeding or migratory schedule, as opposed to animals such as humans   
which seem to be ambivalent about the information.  (I know we are   
slightly tuned to the information as light deprivation studies seem to   
affect this area)  Or an animal who has lost the use of it's pineal gland   
over thousands of years of ambivalence to the information it sends.
 A "less-than-fully-functional pineal gland" may just be one that they   
can't use as a photoreceptor for what-ever reason.  I believe a   
thickening of the bone over the area used to register light (the parietal   
bone in the case of dinosaurs) is an indication that this function is not   
high in the animals which have show thicker coverings over it.  And in   
the animals that have 'filled-in' the area normally assigned to this   
gland with alternative material such as cartilage either arn't using it   
or have some ulterior design we aren't aware of yet.

 -Betty Cunningham