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Testing Pterosaurs

Darren Naish quotes Dr. Kevin Padian in saying: 
<To claim that any set of derived pterosaurs did differently [walked
quadrupedally] requires a complete functional analysis, which entails not
only first-hand analysis of the specimens but also a detailed testable model
of what they actually did -- which has never been produced, to my knowledge.>

I have built full-scale pterosaur skeletons of Dimorphodon, Nyctosaurus,
Pteranodon and others of wood, plastic and wire. They were based on first
hand inspections of actual fossils and casts of many specimens and they
passed inspection (Dr. Padian saw them too) at the last SVP conference in
Seattle.  The models can be manipulated into almost any natural pose. 

I can hang my models quadrupedally from the trunks of pine trees which they
seem perfectly suited to do.  I can balance these skeletons on their hind
legs alone.  I can also put them on all fours on the ground. 

In contrast to the traditional quad model, by keeping the elbows of my models
tucked in (wings folded completely), the wing can move parasagittally by
swinging either at the shoulder or at the elbow.  The foreclaws in this
position extend laterally, matching Pteraichnus prints exactly (in both cases
digit I does not touch the ground). Thus pterosaurs were both bipedal and
quadrupedal, like many living lizards.

The value of a model is not its ability to demonstrate the truth, but to get
closer to the truth than any previous model.  I think these sculptures are a
better model than any illustration because they are much harder to fudge (ie.
subconsciously modify to fit a preconceived paradigm), which is a problem I
see often in the literature and which I have caught myself at occasionally.
(But that's science!)

David Peters