Re: SWIMMING ANKYLOSAURS

["Ralph W. Miller III" <gbabcock@best.com>]

Betty Cunningham wrote:

> Has anyone resolved whether ankylosaurids had air sacs similar to birds?
> (ie: their own natural flotation devices?)

Their is no evidence for this as far as I know.  The article, "Postcranial
Pneumaticity" by Brooks B. Britt, from Currie and Padian's _Encyclopedia of
Dinosaurs_ gives a summary of the topic.  This avian character is apparently
shared (to varying degrees) by pterosaurs, sauropods, and theropods (including
birds), and therefore does not occur among dinosaurs outside the taxon
Saurischia.  Postcranial pneumaticity in saurischians is indicated by the 
presence
of fossae or foramina in the ribs and vertebrae, as these passages are 
interpreted
to be osteological traces of air-filled diverticula.  Extant birds typically
feature pneumaticized vertebrae, ribs, humeri, scapulae, ilia, and femora, the
most notable exceptions being accomplished divers (such as the loons), which
frequently lack postcranial pneumaticity.  So, sorry, no water wings for the
Ankylosauria.

-- Ralph W. Miller III       gbabcock@best.com