"Birds are dinosaurs, that is, they are the direct descendents of an ancestor that spawned the dinosaurs, yet palaeontologists typically refer to dinosaurs while explicitly not referring to birds. Thus one should formally call them non-avian dinosaurs (basically all dinosaurs except birds)."
and
"First off the rhamphorhynchoid pterosaurs (or more properly ‘rhamphorhynchoids’ as the quotes denote it as paraphyletic) which often come up here in my frequent posts on pterosaurs. As with non-avian dinosaurs, the term persists as one of convenience as basically it’s easier to write than “non-pterodactyloid pterosaurs”."
Note the sleight of hand.
The author says:
"Birds are dinosaurs, that is, they are the direct descendents of an ancestor that spawned the dinosaurs".
In other words, birds did NOT evolve from dinosaurs but rather (according to the author) birds and dinosaurs evolved from some OTHER unnamed "common ancestor".
But the author does not make this point clear at all. In fact, he misleadingly compares it to the paraphyletic (ANCESTRAL) rhamphorhynchus relationship which is a true ANCESTOR relationship - an ancestor of pterodactyls.
He talks as if they were the same type of relationship.
Of course it is not the same relationship at all - they are opposites.
NOTE: Birds are not even related to dinosaurs. Cladistics makes it even more difficult to establish correct ancestry. In this post I am just showing the absurdity of cladistics. If we just kept to ancestor/descendant relationships we would not have these cladistic obfuscations.
An excellent analysis of issue with cladistics:
http://joelvelasco.net/teaching/systematics/laporte%2005%20-%20single%20tree%20of%20life.pdf.
The author is in error (or at least unclear). Birds are descended from a very particular group of dinosaurs. They are deeply nested within dinosaurs. They share a more recent common ancestor with some dinosaurs than with others.
ReplyDeleteThis has been pointed out to you on numerous occasions. Why are you still repeating this nonsense?
This author is one of the well-known researchers in the field. I think he would be surprised to hear you say that he is wrong.
ReplyDeleteIn fact, what he has done is that he has made a simple statement about cladistics.
As he put it:
"Birds are dinosaurs, that is, they are the direct descendents of an ancestor that spawned the dinosaurs" (See note below)
And of course, that is the point I have made about cladistics. Which shows how absurd cladistics is.
I suggest you ponder that, rather than just try to rationalize yourself out of it.
NOTE:
In other words, birds did NOT evolve from dinosaurs but rather (according to the author) birds and dinosaurs evolved from some OTHER unnamed "common ancestor".