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Re: Long-necked stegosaur coming out in Proceedings B

Dann Pigdon wrote:

> Keep in mind that the modern analogues mentioned above are
> all sprawl-limbed ectotherms.
> I believe porcupines tackle their predators tail-first -
> then again, they have much more extensive 
> armoury for their size, the spread tail spines easily
> eclipsing the rest of their body.

The armory of stegosaurs also varied markedly among genera.  Taxa like 
_Stegosaurus_, _Hesperosaurus_ and _Huayangosaurus_ had most (if not all) of 
their firepower concentrated in the terminal tail spikes ('thagomizer').  For 
_Stegosaurus_ and_Hesperosaurus_ the rest of the osteoderms, along the dorsum 
of the neck, back and most of the tail, were tall, thin and 
subrectangular/subtriangular in shape.  _Huayangosaurus_ had rather undersized 
plates.  _Miragaia_'s plates (the ones we know of) were somewere in between, 
but we don't know what the armor was like for the posterior half of the animal.

Some stegosaurs had much 'spikier' armor than _Stegosaurus_ and co., especially 
along the posterior half of the animal.  Such as _Kentrosaurus_, which has five 
pairs of sharp spines down its tail.  _Chungkingosaurus_ seems to have had 
maybe four pairs of tail spines.  _Tuojiangosaurus_ had a bona fide thagomizer, 
but there were also some rather long and sharp spines sticking out from the 

Also, some stegosaurs (e.g., _Kentrosaurus_, _Loricatosaurus_, and especially 
_Gigantspinosaurus_; but not _Stegosaurus_ and its closest relatives) had 
parascapular spines, which were also directed backward.

My point (at last) is that individual stegosaur species would have had quite 
different defensive strategies, depending upon the 'armory' each species was 
equipped with.  All stegosaurs were probably united by a preference for facing 
away from a predator (like tail-clubbed ankylosaurs would have done).  But 
beyond that, the defensive behavior of _Stegosaurus_ may have differed quite a 
lot from that of, say, _Kentrosaurus_, or _Loricatosaurus_, or maybe even 
long-necked _Miragaia_.