Re: Feather Flap

[Tim Williams <twilliams_alpha@hotmail.com>]

Don Ohmes wrote:

> Being more interested in convincing selective scenarios than precise 
> kinship, I am somewhat agnostic here. That said, can anyone tell where (and 
> why) the "plant-eating habits" in the article quote pasted below came into 
> the proposed selective process?

Yes, it's a curious remark that appears to be out of context.  My guess (and 
that's all it is) is that the writer might have been referring to 
therizinosauroids (segnosaurs) and/or basal oviraptorosaurs like 
_Incisivosaurus_.  These taxa have been interpreted as plant-eaters, and 
they evolved from carnivorous theropods.

> In either trees down' or 'ground up' I think predatory lifestyles work a 
> lot better for evolving feathered flight...

I could give you an argument on that.  :-)

> "Current theory says that over time theropods developed plant-eating 
> habits, grew feathers to keep warm, and took to the trees for safety."

The first is true, the second is probably true.  The third might be true, 
but I can think of other reasons why a small theropod might have headed up 
into the trees.  In any case, all three evolutionay shifts (herbivory; 
feathers; arboreality) were probably independent events.

David Marjanovic wrote:

> Nope. Feduccia simply asserts, on the second page of that article, that 
> *M.* was a bird and that the resemblance to "small dinosaurs" is 
> "superficial".

It should be noted that Feduccia used to claim (quite vehemently in fact) 
that the resemblence between _Archaeopteryx_ and dromaeosaurids was entirely 
superficial.  Now he believes that dromaeosaurids were secondarily 
flightless birds.

> Problem solved, everyone happy. Also quoted is Storrs "BAND leader" Olson 
> making... peculiar... accusations.

I thought Unwin's comments rang true.  If a good hypothesis is challenged, 
it can only become stronger in the end.  I'd bet this will be the case for 
the presence of "protofeathers" in _Sinosauropteryx_, and the larger 
hypothesis concerning the origin of feathers in theropods.

Cheers

Tim

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