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Re: pterosaur tracks from SVP



-----Original Message-----
From: James R. Cunningham <jrccea@bellsouth.net>
To: larryf@capital.net <larryf@capital.net>
Date: Saturday, October 30, 1999 9:29 AM
Subject: Re: pterosaur tracks from SVP


>Larry,
>I think I may have exceeded my quota for the day, so I'm not copying
>this to the list. Inserts follow.  You may forward this to the list if
>you wish.
>
>Larry Febo wrote:
>
>>  >Although I can see bipedalism in the smaller (earlier) pterosaurs, I
>> also have difficulty seeing them as bipeds in their much larger forms.
>> Especially with partially folded wings. Even minor gusts would have
>> made a bipedal stance fairly unstable.<
>>
>> Quite true.  Qn's head and neck also stuck out about 17 feet past the
>> shoulders, and the neck would have had to have been held nearly
>> vertical if bipedal (due to limits on the articulation).  with the
>> neck about vertical, and the head horizontal, the animal would have
>> been almost 20 feet tall in the bipedal condition, and most unstable
>> to any upset.
>>
>> >Then again, the relatively long metatarsals don`t seem appropriate
>> for a strictly plantigrade stance either.<
>>
>> In Q, the stance is beautifully plantigrade.
>>
>> >Perhaps they (the larger forms)  were capable of both modes, and went
>> digitigrade when sprinting for a takeoff?<
>>
>> My work appears to indicate Q didn't sprint to take off, but did it
>> from a standing start.
>>
>> >In a forward momentum, the apparently overweighted front end would
>> not be a problem.<
>>
>> ???  The front wasn't overweighted.  Perhaps I didn't pick up your
>> meaning.
>

I meant everything front of the hip joint seems heavier than everything
rearward in pterodactyloids (minus the long counterbalancing tail). I know
Padian states that the wing bones are deceptively lightweight due to air
spaces , but, there were flight muscles attached that weren`t lightweight
...no? They seem obviously front heavy to me.