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Re: Feduccia's delusion



 
Feduccia's work is not unscientific.  [...] His real objection to saying BAD things is that BAD things are based on the assumption that certain traits are homologous.  He has concluded thru non cladistic means, by means of "expertise" that the proposed synapomorphies are actaully homoplasius.
The real phenomenon, meanwhile, is that Feduccia doesn't mention lots of evidence against BAND in his writings. I prefer to believe that he simply doesn't know it, but that implies that he doesn't read e. g. Nature, let alone JVP... I'm not comfortable with saying that.
 
I mean, he still says that conical, unserrated teeth are a special characteristic of birds and don't occur in any "dinosaur". This is doubly wrong -- firstly, such teeth could simply be an autapomorphy of birds and not say anything about where birds came from, secondly, there are Pelecanimimus, Byronosaurus, Microraptor, and parts of the dentitions of many others. He never mentions those. Same for the semilunate carpal -- he says "only 4 dinosaurs" have it, which is likewise doubly wrong (these 4 could be the closest relatives of birds, and much more than 4 species have it). Same for feathers -- against all evidence he maintains that the stuff on Sinosauropteryx consists solely of internal collagen fibers and presents 0 arguments for this, as well as 0 arguments against the arguments that they are protofeathers. And so on. It's even worse with his "avimorph thecodonts" -- all they share with birds are a pointed skull and a relatively long neck, but they aren't even archosaurs, all of them.
        He has his idea that BAND, and then he goes out to attack, by almost whatever means, everything that he can find that doesn't support it. This is not science.
        In his 1999 second edition of his 1996 book, he writes (judging from a review; I haven't read the book) that all similarities between Compsognathus and Archaeopteryx are due to convergence. Then he argues that Compsognathus, like Sinosauropteryx, was an aquatic lake dweller, while Archaeopteryx is totally arboreal! Convergence is caused by similar selective pressures, usually or always caused by similar ways of living, no? BTW, I really wonder where Feduccia gets a freshwater lake (or even a salt lake) from in Solnhofen, but maybe that's not implied and he talks of a lagoon. Or so I hope.
The arguement against fedduccia is often that the synapomorphies yeild BAD.  This of course is neither an arguement against the BAND nor is it a response to the BAND.  To do that you need to argue that the supporting synapomorphies are in fact synapomorphies,
Has been done. Such an investigation is called a cladistic analysis.
or agrue that the explantions given for homoplasy are wrong.
The sheer number of characters that would have to be convergent under BAND (over 100) is a good argument.
feathers [...] cant be shut off for a while (phylogentically) and then switched back on.....at least i dotn think they can be!?
Genes can probably be shut off for "a while" (imagine a mutation that destroys the start codon, and then another that repairs it), but not for "very long", because shut-off genes (called pseudogenes) can accumulate mutations, without natural selection working on them, that would prevent them from working should the start codon happen to come back. No idea on the actual amounts of time involved.
 
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