Re: Therizinosaur Feeding (the Chalicothere Angle)

["Jaime A. Headden" <qilongia@yahoo.com>]

Tim Williams wrote:

<Russell and Russell (1993) suggest a chalicothere-
analog for _Therizinosaurus_.  Like _Chalicotherium_
(a horse & rhino relative from the Tertiary), the long
arms and claws of _Therizinosaurus_ may have been used
for pull down large tree branches to bring the leaves
within reach of the mouth. They picture
Therizinosaurus as a short-tailed prosauropod-like 
herbivore, with extremely long forelimbs and fingers,
perhaps sitting down during feeding.>

  The chalicothere analogy only goes so far, and falls
short of the fact that chalicothere claws were
modified hooves, were cloven (each claw, fore and
hind, split up the middle half or so of its length)
and were _much_ broader proportionate or the arm than
in therizinosauroids, and were also quadrupeds (check
out Carroll, 1988, for a quickie on these; these arms
would have served a different function than in
therizinosauroids, as seen from my eye. (Coombs has
done a variety of papers on the subject of
chalicotheres (his 1983 being especially relevant to
the discussion).) Therizinosauroids lacked extremely
short tails, as *Alxasaurus* and the new
*Beipiaosaurus* show, though I'm only hypothesizing
about the big'uns (20ft+ and more) based on parsimony,
and very probably would not have been quadrupedal, as
per the prosauropod model. (see Russell and Dong,
1993; and Xu et al., 1999; see Paul, 1986, 1990; and
Lambert, 1996 for views on the quadrupedal stance.)

  When I'm finally finished with my upgrades and I get
Qilong back online (completely, some of it's already
up, looking better) there'll be a section on other
dinosaurs and several new essays [with refs],
including the spinosaurs and segnosaurs. You'll all
see

... 
hahahahahahahahahahahahahahahahahahahahahahahahahahahahahahahahahahaha!!!!!!!!!!!!!!!!!!

===
Jaime A. Headden

"May I lure us, ere the mote ends us?"

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