Saturday, December 1, 2012

Making the Connection

James and Pourtless' analysis links Longisquama with birds.
And Peters' work links Longisquama (and other protopterosaurs) to pterosaurs.
I propose that protopterosaurs (eg. Longisquama, cosesaurus) developed into pterosaurs which in turn developed into birds.

James and Pourtless list Longisquama as a possibilty as follows:
 "These results nevertheless support the possibility of a
sister-group relationship between Longisquama
and Aves (inclusive of some maniraptorans)."

In fact, Longisquama is a good candidate along with the other protopterosaurs such as Sharovipteryx and Cosesaurus.
If Sharovipteryx was a relative of pterosaurs, then its membrane may have stretched to its front legs, or it may have had a separate membrane joined to its front limbs alone. A secondary membrane is visible between the thighs and the trunk. Front wing membranes have not been seen; Peters (2006) has claimed to have traced the fingers[2] and that they show similarities to Cosesaurus and Longisquama and to a lesser extent, pterosaurs.
This is an important connection to the idea of protopterosaurs (David Peters' work). This is consilience.

No comments:

Post a Comment