[Taxacom] Kinman System, dinosaurs, and bird classification

Ken Kinman kinman at hotmail.com
Fri Jul 28 23:12:42 CDT 2006

Pierre and Christopher,

     Before I get into the Kinman System, I thought I would answer Pierre's 
question about where dinosaurs end and birds (Class Aves) begin.  Exactly 
where to draw the line between Reptilia and Aves is no longer easy (and 
increasingly arbitrary to a degree with so many more intermediates being 
known now).  However, Archaeopteryx and its deinonychosaur relatives 
(Archaeopterygiformes) should clearly be placed near the base of Class Aves 
since Archaeopteryx has been recognized as a bird from the time of its 

      These are the forms where we see the beginnings of the true semilunate 
carpal block (in the wrist) and also eggs with ornithoid microstructure.  It 
is also fairly close to the origin of lateral shoulder joints, vaned 
feathers, enlargement of the sternum, and other birdlike characteristics.  
The immediate outgroups are the bird-like dinosaurs, such as families 
Segnosauridae, Ornithomimidae, and even Tyrannosauridae.  We can quibble 
about the details of a precise synapomorphy for the origin of birds, but the 
wrist morphology and eggshell microstructure seem to show an excellent area 
in which to make the division.  Deinonychosaur "dinosaurs" would have been 
immediately classified as birds had we known about their feathers and 
ornithoid eggs.

       Below is the classification of Class Aves which I posted on Taxacom 
earlier this year.  It is divided into two subclasses, a paraphyletic 
Archaeornithes giving rise to Neornithes.  As I have stated many times, I 
see no advantage whatsoever in restricting taxon Aves to only the Neornithes 
(modern birds) as Gauthier and other strict cladists have proposed (mainly 
because it is a "crown clade").  It just seems silly and arbitrary to me to 
exclude Archaeopteryx from Aves, and it is also redundant to equate Aves 
with Neornithes.

    I have explained the Kinman System and its coding at various times 
(using various taxa) for about 8 years now (see the Taxacom archives), but 
here are the highlights.  My 1994 book explains it in more detail, but there 
are no copies in the Sacramento area.  Paraphyletic groups are allowed 
(actually necessary, although I use them sparingly), and their names marked 
by a % sign.  The descendant exgroups of such paraphyletic groups are coded 
by an underlined alphanumeric symbol (usually _1_ or _a_).

    The main cladistic code is alphanumeric, with numbers showing the main 
branching of clades in the order that they split off (and subsidiary 
subclades coded by letters).  Phylogenetic uncertainty is obviously 
indicated by a question mark coding.  Neornithes clade 3 (Pterocliformes 
through Eurypygiformes) is still not fully coded as their phylogeny is still 
very uncertain.  Note that among the extinct groups within Archaeornithes, 
there are some genera not formally assigned to families, and therefore still 
referred to as "Plesion" (usually abbreviated Pl.).  Note that I broke down 
Order Archaeopterygiformes to family level here because it is very 
paraphyletic and has been expanded to include what are normally classified 
as dinosaurs).  Velociraptorids and Dromaeosaurids are increasingly being 
recognized as large flightless birds, and their much smaller flying 
ancestors will no doubt be discovered in the future.

           CLASS AVES

        1  Archaeopterygiformes%
                1  Troodontidae
                2  Velociraptoridae
                B  Dromaeosauridae
                3  Microraptoridae
                ?  Plesion Sinovenator
                ?  Pl. Mei
                4  Scansoriopterygidae
                ?  Pl. Unenlagia
                ?  Pl. Buitreraptor
                5  Pl. Rahonavis
                6  Archaeopterygidae
                ?  Pl. Protarchaeopteryx
                7 {{expanded Avebrevicauda}}
        _1_ Yandangornithiformes
         ?  Pl. Shenzhouraptor
         2  Omnivoropterygiformes
         B  Pl. Sapeornis
         ?  Pl. Caudipteryx
         3  Oviraptoriformes
         4  Caenagnathiformes
         ?  Pl. Nomingia
         ?  Avimimiformes
         5  Mononykiformes
         6  Confuciusornithiformes
         7  Longipterygiformes
         B  Iberomesornithiformes
         C  Enantiornithiformes
         D  Gobipterygiformes
         8  Chaoyangiiformes
         9  Patagopterygiformes
         ?  Pl. Hongshanornis
        10  Yanornithiformes
        11  Ambiortiformes
        12  Hesperornithiformes
        13  Ichthyornithiformes
        14  Pl. Limenavis
        15  Lithornithiformes
        16  {{Neornithes}}

_a_ NEORNITHES (crown clade, "modern" birds)
         1  Tinamiformes%
        _a_ Struthioniformes (ratites)
         2  Galliformes
         B  Anseriformes
         3  Pterocliformes
         B  Columbiformes
         C  Caprimulgiformes%
        _a_ Apodiformes
         D  Mesitornithiformes
         4  Turniciformes
         B  Charadriiformes
         C  Gruiformes (sensu stricto)
         5  Ciconiiformes
         B  Pelecaniformes
         C  Procellariformes
         6  Falconiformes
         B  Strigiformes
         7  Cuculiformes
         8  Coliiformes
         B  Psittaciformes
         9  Coraciiformes (sensu stricto)
        10  Alcediniformes
        11  Bucerotiformes
        12  Piciformes
        13  Passeriformes

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