RE: Distributions of morphological characters and more

["Jaime A. Headden" <qilongia@yahoo.com>]

Mickey Mortimer (mickey_mortimer111@msn.com) wrote:

<Choanae are internal nostrils.  Generally formed by the maxillae, vomer and
palatines on the ventral surface of the snout.>

  Well, to be pedantic, the internal nostrils are the fleshy apertures through
which the internal narial passage, accurately called the "choana", passes into
the pharynx or back of the throat. The choana, as defined in medicine, is thus:

  "Choana: (Plural: choanae) The passageway from the back of one side of the
   nose to the throat. There are two choanae, one on either side of the nose.
   The choanae must be open to permit breathing through the nose. The noun
   choana is less used than the adjective choanal, as in choanal atresia
   (blockage of the choanal passage) and choanal stenosis (narrowing of the
   choanal passage). From the Greek choane (a funnel)."
  (http://www.medterms.com/script/main/art.asp?articlekey=39034)

  Wikipedia's EvoWiki (http://wiki.cotch.net/index.php/Choana) uses a much more
simplified, but essentially osteological, definition:

  "The choana is the rostral-most palatal vacuity, bounded by the maxilla,
   palatine and vomers."

  "Choana (plural -nae): A funnel shaped opening, especially either of those
   connecting the nasal cavities to the pharynx."

  (_Oxford English Dictionary_)

  Dorlands uses:

  "choana (cho·a·na) (ko¢[schwa]-n[schwa]) pl. cho¢anae  [L.; Gr. choan[emacr]
   funnel] [TA]  1. any funnel-shaped cavity or infundibulum.  2. (pl.) the
   paired openings between the nasal cavity and the nasopharynx; called also
   posterior nasal apertures and posterior nares."

 
(http://www.merckmedicus.com/pp/us/hcp/thcp_dorlands_content.jsp?pg=/ppdocs/us/common/dorlands/dorland/dmd-c-031.htm)
  [Scroll down, you may have to cut and paste the link]

  The bony opening is perhaps properly referred to as the internal narial
fenestra; just as the external narial fenestra is also called the external
nares, the internal narial fenestra may be called the internal nares or
"posterior nares," as suggested above.

  Cheers,

Jaime A. Headden

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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