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

[Tim Williams <tijawi@gmail.com>]

Matthew Martyniuk <martyniuk@gmail.com> wrote:

> Don't confuse differences in definition with differences in phylogeny.


No, I wouldn't dream of it.  However, it's clear that the BANDits have
an agenda here - no doubts on *that* score.  They equate typology with
phylogeny.  The BANDits claim that any fossil that turns up with
feathers is a "bird", and therefore used its feathers for flight (or
evolved from ancestors that did).


> There's nothing wrong with defining birds as an apomorphy-based clade
> anchored on the presence of feathers (in fact as stated numerous times
> on this list, such a definition was the first one proposed for Aves in
> the 1980s).


I think equating "Aves" (clade) with "birds" (a vernacular term) is
itself fraught with problems - unless Aves is limited to the crown
clade.


If taxa such as _Microraptor_, _Caudipteryx_ and the
scansoriopterygids all get tagged as "birds" it can lead to all sorts
of unsupported ideas about the way these critters behaved.  IMHO, even
calling _Archaeopteryx_ a "bird" is tricky.  It has spawned all sorts
of unwanted assumptions regarding _Archaeopteryx_'s behavior - such as
it was capable of powered flight, and could perch in trees.  After
all, these are things that modern birds can do.  It's also what
Feduccia &c clearly believe _Archaeopteryx_ could do. Yet, the
evidence that _Archaeopteryx_ could either fly or perch is dubious at
best.


> The problem with BANDits is in their phylogeny, not their
> definition of the vernacular English word "birds". Arguing semantics
> with the BANDits just confuses matters. Argue with their science
> instead.


Yes, but in this case it's one and the same.  The BANDits regard the
presence of feathers as being a defining feature of birds, and
therefore any fossil found with feathers is (phylogenetically
speaking) a bird.  Given it's typological history, "bird" is itself a
loaded term.  And applying the term "bird" to taxa such as
_Microraptor_ and _Caudipteryx_ is obviously part of a BANDit
marketing ploy.







Cheers

Tim