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Re: Parts & Non-Recreation (was: Ceratonykus)

2011/5/1 Jaime Headden <qi_leong@hotmail.com>:
> I'm jumping on a limb here. Both Augusto and Tom below sent emails that 
> included an address with a listproc identifier, but these did not show up in 
> the archives for the dates sent. I will presume they were intended for the 
> list. Otherwise, I apologize.
No need in my case, I just tried to post to the DML and failed. Thanks
for the courteous manners however.
> Augusto Haro wrote:
> <May that be due to their their phylogenetic inheritance? I mean, if you have 
> a bear with bunodont ancestors that starts eating more insects, you will find 
> an ant-eating bear with smaller bunodont teeth. If you have some coelurosaur 
> with blade-like teeth, and then dental reduction operates because of social 
> insect feeding habits, then I would expect seeing animals with reduced blades 
> instead of reduced bunodont teeth.>
>    While I would agree in general principle that the relevance of phylogeny 
> matters here, such that *Ceratonykus oculatus* itself inherited an 
> opisthopubic pelvis, this sin't true for alvarezsaurids as a whole: 
> *Haplocheirus sollers* has a propubic pelvis, and *Patagonykus puertai* 
> either propubic, mesopubic, or just slightly opisthopubic. None of them are 
> remotely as odd as the ornithischian-level of "parvicursorines" where the 
> pubis and ischium are in contact for nearly their entire lengths, thin, 
> slender, and fairly short. In *Patagonykus puertai,* for example, the arm is 
> highly modified from the condition in *Haplocheirus sollers,* as is the 
> pelvis, based on the preserved fragements; yet the pubis is not attenuated or 
> modified into the splint-like rods of "parvicursorines." Based on its 
> curvature, and I think that alone, I suspect the pubis is procurved and 
> mesopubic, which is the inverse of what is usually depicted...
Sorry if not clear enough in my responses (and thanks for the
information about the alvarezsaur pelvis!) but my point was directed
towards teeth. I mean, you brought into consideration the shape of the
teeth of alvarezsaurs while (apparently) dismissing the possibility
that they were myrmecophagous. I just attempted to say that the teeth
reduction seemed concordant with myrmecophagous habits, and its
carnivorous theropod-like features such as being blade-like may be
explained just because of phylogenetic heritage (the true adaptation
being thus the reduction).