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Re: What is big, fluffy, and could tear you to shreds? Yutyrannus, the 9 m long feathered tyrannosauroid from China



Dr Ronald Orenstein <ron.orenstein@rogers.com> wrote:


> However: I was looking specifically for one thing and failed to find it. 
> Feduccia's current thesis requires (it would seem to me) accepting that
> maniraptorids are convergent to dinosaurs.


I can't top Tom's response, but some background information is useful.
 There was a time back when Feduccia &c regarded the similarities
between _Archaeopteryx_ and maniraptorans to be the result of
convergence.  Feduccia himself once argued this point quite forcefully
(and erroneously).


Then non-avian maniraptorans were found with feathers - such as
_Caudipteryx_, _Protarchaeopteryx_ and _Microraptor_.  Oops.  The
response by Feduccia &c was to then argue that these maniraptorans
were either secondarily flightless birds or stem birds, and that this
entire collection of feathered taxa evolved independently of "true"
theropods.  Feduccia &c were aided and abetted in this dodgy venture
by the publication of "The Dinosaur Museum Journal" in 2002 by the
Czerkases, which argued much the same point: that the
bird/maniraptoran lineage and the theropod lineage evolved separately
from a common Triassic stock.


It's all as ludicrous as arguing that hominoids (apes and humans)
evolved independently of a group made up of lemurs, tarsiers and
monkeys, from a common stock of basal primates.  But arguing that
feathered maniraptorans+birds have a separate origin to theropods from
a shared archosaurian stock is the only way the BANDits can try and
keep their "hypothesis" alive.  There is an element of desperation to
the BANDits attempts to re-write bird-archosaur evolution every time a
significant feathered fossil comes to light.  The BANDit mindset is
rooted in the outdated, typological mindset that any fossil showing
true feathers *must*, by definition, be a bird.  As they themselves
put it: "...birds are monophyletic and are nicely defined by their
unique possession of feathers."






Cheers

Tim