MINIATURISING DACENTRURUS

[darren.naish@port.ac.uk]

Jaime wrote...

> The smallest stegosaur: *Dacentrurus* and a few
> other specimens, such as those refered to the few
> Chinese taxa you can barely pronounce the names of
> (*Chialingosaurus*, *Chungkingosaurus*, etc.), are
> around 12ft. long. [see below for a possibly smaller
> animal]

Ooops: any individual of _Dacentrurus_ that was about 12 ft long 
would have been a juvenile... _Dacentrurus_ is a BIG animal, there 
being femora more than 1 m long and a complete pelvis from the 
Kimmeridge Clay that is something absurd like 1.5 m across at the 
acetabula. Some of this material scales up to suggest individuals of 10 
m total length - you'd have to check all the literature for the facts (lots 
of obscure little Galton papers) but it looks like _Dacentrurus_ was a 
giant, and perhaps the biggest stegosaur. Incidentally, here I'm talking 
about _D. armatus_.

Why virtually all dinosaur books refer to _Dacentrurus_ as small, and 
give it lengths of 4-5 m, is beyond me: Peter Dodson draws attention 
to this phenomenon in his book. Basically, it's because many dinosaur 
books are not written by people familiar with either the specimens or 
the technical literature AND because books tend to copy 'facts' 
promulgated by earlier ones.

DARREN NAISH 
PALAEOBIOLOGY RESEARCH GROUP
School of Earth, Environmental & Physical Sciences
UNIVERSITY OF PORTSMOUTH
Burnaby Building
Burnaby Road                           email: darren.naish@port.ac.uk
Portsmouth UK                          tel: 01703 446718
P01 3QL