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Re: Dinosaur Genera List update #196
David Marjanovic (email@example.com) wrote:
<IMHO they are more like *Rahonavis* than *Archaeopteryx*, but not
necessarily more like Pygostylia than *A.* apart from convergences. For
example they have a joint between coracoid and scapula, while *Sapeornis*
has a suture in that place and *Confuciusornis* fuses them like a
My data shows the following features which *Archaeopteryx* and
*Rahonavis* lack, to one degree or another, or are advanced to the level
of *Confuciusornis*, and some features go beyond it, as well.
1) Sternum has a lateral trabeculum;
2) coracoid acrocoracoid process at the very proximal end of the bone,
projecting cranially and not rectangular in form;
3) Furcular rami are flattened, crescentic in section, broad in section,
and form a "V" rather than a "U";
4) Ulna bowed only at the proximal end;
5) Metacarpal I bears a large extensor flange;
6) Radius distally broad and overlaps the ulna in a tight, sliding
implying the distal end is very crescentic in section itself;
7) Metacarpal III bowed externally, mcIII extends distally beyond mcII;
8) Manual digit 1 (mdI) extends to knuckle of mdII, not distal to it;
9) Ulnare large and well-developed for the carpometacarpal articulation;
11) Humerus bears three distal condyles, third formed from entepicondyle;
12) Ischium has an longate, strut-like proximodorsal process that may or
may not have articulated with the ilium.
Jaime A. Headden
Little steps are often the hardest to take. We are too used to making leaps
in the face of adversity, that a simple skip is so hard to do. We should all
learn to walk soft, walk small, see the world around us rather than zoom by it.
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
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