Re: *Longisquama* Furcula?

[Dinogeorge@aol.com]

In a message dated 8/13/99 4:36:50 PM EST, qilongia@yahoo.com writes:

<<  Given the nature of the avian furcula as a
 spring device to aid in wingbeats and/or respiration,
 and the total lack of any forelimb adaptation in
 *Longisquama* for gliding, active or passive flying,
 powered flight, etc., what would be the funtional use
 of a furcula in an animal that -- to my eyes -- looks
 a lot like the drepanosaurs and megalancosaurs, and
 like them, like a chameleon (that's arboreal, not
 aerial). In such an animal, the forelimbs and shoulder
 girdles must swing forward and back to accomodate
 locomotion, and a furcula would only hinder this. Even
 terrestrial lizards swings the shoulders to walk, and
 so does *Draco*, the flying lizard. >>

This question is addressed by Haubold & Buffetaut

Haubold, H. & Buffetaut, E., 1987. "Une novelle interprétation de Longisquama 
insignis, reptile énigmatique du Trias supérieur d'Asie centrale [A new 
interpretation of Longisquama insignis, an enigmatic reptile from the Upper 
Triassic of Central Asia]," Comptes Rendus Académie des Sciences du Paris 
305, Série II: 65?70.

who aver that the furcula might have functioned as a shock absorber in 
arboreal leaping.

Megalancosaurids and Longisquama, and Cosesaurus, might indeed be closely 
related, as I suggested in Mesozoic Meanderings #2 by classifying them in the 
order Basitheropoda. Now that we have postcranial skeletons for 
Megalancosaurus, I'm not nearly so sure they belong in the same order.