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David's question




David,
I don't formally recognize intermediate taxa, like Paleognathae or Neognathae, in my classifications. Only the main ranks like Class, Order, Family. The coding to the left of the taxa show relationships, so while phylogeneticists continue to increase the numbers of formal taxa, I have decreased the numbers of formal taxa from what even most eclecticists generally use. For example (in brief; I hope this lines up okay on everyone's screens):
CLASS REPTILEA (reptiles, sensu lato)
1 Pelycosauriformes
_a_ Therapsiformes
_a_ {{Mammalea}}
2 Mesosauriformes
.........etc.
8 Saurischiformes
1 Guaibasauridae
...... etc.
14 Dromaeosauridae
? Alvarezsauridae (inc. sed.)
15 {{Avea}}
_a_ {{Avea}}
9 Ornithischiformes
*************************************************
_a_ CLASS AVEA (emended from Aves)
1 Archaeopterygiformes
.......etc.
5 Hesperornithiformes
6 Ichthyornithiformes
7 Tinamiformes
_a_ Struthioniformes (ratites)
8 Galliformes
B Anseriformes
9 Ciconiiformes
B Pelecaniformes
C Procellariiformes
10 Charadriiformes
........etc.
The main cladistic sequence is numbered, subsidiary sequences are capital letters, and the underline "a", _a_, shows Tinamiformes is paraphyletic with respect to Struthioniformes (sensu lato; ratites), and that the sister group of ratites therefore is to be found within Tinamiformes.
Likewise the _a_ shows AVEA (birds) have a sister group within Ornithischiformes, and I present code that sister group to be Dromaeosauridae. If you want to show Alvarezsauridae to be sister group to birds, you could code it like this:
14 Dromaeosauridae
15 Alvarezsauridae
16 {{Avea}}
In the bird classification, I can refer to a clade Aves 7, or call them palaeognaths. And I can refer to a clade 8+, or call them neognaths. Together they form clade Aves 7+ ("Neornithes"; neornitheans). But with such coding (which can be changed if the cladogram changes), I don't have to formally name every clade (and just give informal names to the most important "intermediate taxa" (neornitheans, neognaths, etc.).
-----Ken
P.S. And I wouldn't totally agree that cladists have given up ranks-----they just have so many that they just stopped giving labels to the ranks.
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