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FW: Oviraptorosaur tail forms and functions



Pardon; this was sent accidentally only to the two respondents.

----------------------------------------
> From: qi_leong@hotmail.com
> To: tijawi@gmail.com; augustoharo@gmail.com
> Subject: RE: Oviraptorosaur tail forms and functions
> Date: Sun, 13 Jan 2013 20:53:59 -0700
>
>
>   No matter, the hypothesis must reason how the elongated, flexible but 
> perhaps far stiffer tail of dromaeosaurids, the less-stiffened tail of 
> *Archaeopteryx* spp. and the short and somewhat or very flexible tail of 
> oviraptorosaurs with its occassionally stiffened tip can be produced if by 
> the same forces or constraints on behavior. This is especially important if a 
> role in retrex-support and extent of such things is taken into account, as by 
> all specimens recovered so far these things differ among the taxa.
>
> Cheers,
>
> Jaime A. Headden
> The Bite Stuff (site v2)
> http://qilong.wordpress.com/
>
> "Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
>
>
> "Ever since man first left his cave and met a stranger with a
> different language and a new way of looking at things, the human race
> has had a dream: to kill him, so we don't have to learn his language or
> his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 
> Backs)
>
>
> ----------------------------------------
> > Date: Mon, 14 Jan 2013 14:37:35 +1100
> > From: tijawi@gmail.com
> > To: dinosaur@usc.edu
> > Subject: Re: Oviraptorosaur tail forms and functions
> >
> > Ronald Orenstein <ron.orenstein@rogers.com> wrote:
> >
> > > I sent a query to the list that may have been lost in truncation: is it 
> > > possible that the tail did serve an "aerodynamic" function, or at least a 
> > > stabilizing function in running
> > > (perhaps to make balancing or banking adjustments during rapid twists and 
> > > turns), rather than for defense or display (though of course a colourful 
> > > tail fan could still have
> > > a display function)?
> >
> >
> > This probably doesn't answer your question, but there is a hypothesis
> > (Carrier et al., 2001) that reduced tail length reduced rotational
> > inertia in maniraptorans, and therefore improved their ability to make
> > sharp turns when running . This effect would be enhanced if the tail
> > was not only short, but stouter closer to the base of the tail. But
> > this hypothesis doesn't explain the development of terminal fusion of
> > the tail vertebrae (such as forming a pygostyle), nor the presence of
> > large feathers on the tail (including a tail "fan").
> >
> >
> > Other hypotheses have proposed that large distal tail feathers could
> > help with aerial ground-to-air leaps (Caple et al.,1983), or leaps
> > from elevated surfaces to the ground (Garner et al., 1999). The
> > former emphasizes the role of lift, the latter drag, in these
> > incipient flight behaviors. But both models emphasize the role of the
> > feathered forelimbs and tail in controlling body orientation while in
> > the air, because in both cases the purpose of these leaps is prey
> > capture (flying insects or terrestrial prey, respectively).
> >
> >
> >
> >
> >
> >
> > Cheers
> >
> > Tim
> >
> >
> >
> >
> >
> > Cheers
> >
> > Tim
>