http://en.wikipedia.org/wiki/Dromaeosauridae#Flying_and_gliding
"As late as 2001, Mark Norell and colleagues analyzed a large survey of coelurosaur [maniraptor] fossils and produced the tentative result that dromaeosaurids were most closely related to birds, with troodontids as a more distant outgroup. They even suggested that Dromaeosauridae could be paraphyletic [ancestral] relative to Avialae."
I am quoting this because it sheds light on the word "paraphyletic".
"Paraphyletic" means ANCESTRAL!
It would be a helpful exercise to substitute the word "ancestral" whenever we see the word "paraphyletic".
There is certainly nothing wrong with being "paraphyletic" since it simply means ANCESTRAL.
I was quite surprised/pleased to see this:
ReplyDeletehttp://en.wikipedia.org/wiki/Modern_birds
"In traditional classification, the Neornithes also included a third superorder, the Odontognathae, containing advanced toothed birds from the Cretaceous, like Hesperornis and Ichthyornis.[5] This superorder is likely paraphyletic [ANCESTRAL], and fall outside [ancestral to] the crown group birds. It is not entirely clear whether the Palaeognathae too are paraphyletic, or represent a primitve grade of birds.[6]"
This seems to be saying exactly what I have been saying.
Modern bird taxa developed from such taxa as Hesperornithes and Ichthyornithes etc.
And other people have also been saying much the same thing. But it does not support your notion that specific modern groups are descended from specific members (or unknown members of families) of the Odontognathae. It is still saying that all living birds are more closely related to each other than to any of these extinct species.
ReplyDeleteA Nonny Mouse could you please elaborate on what you mean by saying that all living birds are more closely related to each other than to any of these extinct species.
ReplyDeleteAnd I do not mean a general description but specifically what you mean, by referring to specific traits.
Living birds form a group which share a more recent common ancestor than they do with the "Odontognathae". If you read the links Wikipedia provides at the bottom, and look at other references, such as Julia Clarke's Ichthyornis monograph you should see what I am talking about, and that would give you a list of characters- characters that have already been mentioned elsewhere, and which you have ignored.
ReplyDeleteA Nonny Mouse is not supporting his point. Anyone else care to try to support his point?
ReplyDeleteI have suggested that modern seabirds (eg. albatrosses) developed from an Ichthyornithes subgroup:
ReplyDeletehttp://pterosaurnet.blogspot.com/2011/10/seabirds_3981.html
However, A Nonny Mouse posted:
"It is still saying that all living birds are more closely related to each other than to any of these extinct species."
So for example, are we to think that modern seabirds such as albatrosses are more closely related to hummingbirds, than albatrosses are to Ichthyornithes?
Can anyone support that assertion?
What specific characteristics are you looking at to make that assertion?
Paraphyletic has its own entry:
ReplyDeletehttp://en.wikipedia.org/wiki/Paraphyly
Read it carefully (for once) to understand the relation between 'paraphyletic' and 'ancestral'.
Hello Anonymous.
ReplyDeleteCould you include a made-up name in your comments please?
That way we can avoid confusion.
'Paraphyletic' means ancestral. Think about it.
Cladistics does not acknowledge ancestral relationships. Which is surpassingly odd.
But I am not getting into a long discussion on this.