[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

re: T&F talks, SVP, Pteraichnus

Jaime Headden wrote:

Jean-Pierrer Billon-Bruyat gave a fascinating summary of work on a set
of *Pteraichnus* tracks that show a foot-first, then down to all-fours
landing pattern in a pterosaur, and subsequent quadrupedal walking. Tow
claw scratch-marks aside, very fascination implications, especially since
one of the authors of the abstract at the time I think still considers
pterosaurs to be bipedal.

I wasn't one of the authors, but I corresponded with "one of the authors" to 
produce the animation of the landing pterosaur. "One of the authors" 
understands that tracks demonstrate that this genus/clade of pterosaurs walked 
flat-footed and quadrupedal. 

Every attempt was made to match manus and pes impressions to a known genus, 
something that had not been done in previous work. I think the important point 
that "one of the authors" might want you to walk away with is that this 
pterosaur landed on two feet and with only a small squeak of its landing gear, 
came to a full stop within two pedal lengths of its first touch down. So, it 
was adept at landing. Afterwards, a bit of bipedal wing folding took place 
before quadrupedal walking commenced. Finally, the configuration of the 
quadrupedal walking had the backbone elevated, much as Chris Bennett has shown 
with Pteranodon and Nyctosaurus, but unlike what Chris Bennett and David Unwin 
have shown with Pterodactylus which has been reconstructed with a horizontal 
backbone. In fact, as Chris has published with regard to Nyctosaurus, bipedal 
or quadrupedal was essentially the same configuration. I echo that comment, but 
extend the same configuration to all pterosaurs. 

Some animations of competing hypotheses of pterosaur walking can be seen at:


I'll add the pterosaur landing animation when given the green light by "one of 
the authors".

More later,
David Peters
St. Louis