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Re: Anatomical directions for decribing coracoids



David Marjanovic writes:
 > > (And let's not even get into the use of cranial/caudal for
 > > anterior/posterior!  If I read one more papar about cranial
 > > caudal elements, or caudal cranial elements, I'm going to have to
 > > go get that Quad Damage and do some harm.)
 > 
 > Instead of the former, you're supposed to say "proximal
 > caudal". Regarding the latter, in cases where "occipital" doesn't
 > fit, I don't know why more people don't follow Gerald Mayr's
 > extension of "proximal/distal" to the neck and skull. Perhaps it's
 > because it clashes with toothrow nomenclature, where "distal"
 > suddenly means "away from the symphysis", which in turn means
 > "toward the jaw joint" except in exceptions like *Nigersaurus*. I
 > think the toothrow nomenclature should be changed... :-}
 
Pish and tosh, sir!  Anterior = towards the front, posteior = towards
the back.  That's all you need.  You can keep all your craniorostal
bobbins.

(Disclaimer: I wrote this message partly in order to annoy Jerry.  One
day, I can going to translate "The axial skeleton of the dinosaur
_Suuwassea emilieae_ (Sauropoda: Flagellicaudata) from the Upper
Jurassic Morrison Formation of Montana, USA" into proper anatomical
nomenclature and send it to the Polyglot Paleontologist :-)

Actually, maybe I am kind of serious.  I am not even totally convinced
by proximal and distal for limb elements.  Here's why: you still need
to be able to refer to the other four orthogonal direction as well as
proximal and distal, so that for example you can say that the fourth
trochanter projects medially as well as posteriorly.  Well, once
you've admitted that the other four direction are medial, lateral,
anterior and posterior, you've pretty much given the game away that
your "proximal" is dorsal and your "distal" is posterior.  You see
this oh-what-a-giveaway thing happening every time someone writes
something like "the deltopectoral crest is about one third of the way
down the humerus".  Down, you say?  Oh, what a giveaway!  So I say
let's drop _all_ the other directional terms and just stick with
dorsal/ventral, lateral/medial and anterior/posterior.

(Real, serious disclaimer this time: I realise all this is much easier
for well-behaved tetrapods, such as sauropods, than it is for
penguins, kangaroos, and those pesky humans.)

 _/|_    ___________________________________________________________________
/o ) \/  Mike Taylor    <mike@indexdata.com>    http://www.miketaylor.org.uk
)_v__/\  "We demand rigidly-defined areas of doubt and uncertainty!" --
         Vroomfondel and Majikthise, "Hitchhikers' Guide to the Galaxy"