Re: Archaeopteryx dinosaurian synapomorphies

[Dinogeorge@aol.com]

In a message dated 96-01-21 19:37:48 EST, jpoling@infinet.com (Jeff Poling)
writes:

>As you folks can see, I am getting more and more mail from morons trying
>to disprove a link between dinos and birds.  Somebody PLEASE submit to the
>list a list of synapomorphies archaeopteryx shares with dinos, or direct me
>to where I can find such a list.

What you're looking for are _characters_ that _Archaeopteryx_ shares with
dinosaurs. Most of these characters will be _plesiomorphies_ rather than
synapomorphies, because after all, _Archaeopteryx_ was a pretty highly
derived dinosaur. You want Archy's _apomorphies_, they'll be its birdlike
features.

Here are 20 to get you started (characters shared with/retained from
dromaeosaurids and other related theropods and dinosaurs):

(1) Tridactyl manus with manual digits IV, V lost
(2) Manual digit I robust
(3) Manual digit II longest in hand
(4) Manual digit III slender, with phalanges 3,4 both short
(5) Semilunate carpal
(6) V-shaped furcula present
(7) Straplike scapula
(8) Functionally tridactyl pes with retroverted hallux
(9) Advanced mesotarsal ankle
(10) Splintlike metatarsal V
(11) Ascending process on astragalus
(12) Slender fibula
(13) Femur with orthogonally inturned head
(14) Perforate acetabulum
(15) Pelvis moderately opisthopubic
(16) Pubis long, rodlike with distal expansion
(17) Bladelike ilium
(18) Sacrum with at least 5 vertebrae (_A._ has six)
(19) Long tail, distally stiffened
(20) Jaws with teeth

There are dozens more--I've scarcely touched the skull in this list. But you
get the idea, yes?