Re: Size of *Neoceratodus africanus* and/or *N. tuberculatus*

[Tim Williams <tijawi@yahoo.com>]

Raptorial Talon <raptorialtalon@gmail.com> wrote:


> I suppose the bottom line is, why were animals as large as spinosaurs
> possessed of such an unusual head/neck morphology? Pretty much every
> other group of large theropods has robust skulls adapted to
> either hacking/slashing or gouging/crushing - features suitable
> for big predators taking big prey. 


Briefly, there are several large to very large theropods that do not appear to 
have been specialized for taking big prey: _Therizinosaurus_, _Gigantoraptor_, 
and possibly _Deinocheirus_ (especially if an ornithomimosaur).


> Yet spinosaurs are virtually antithetical
> to this arrangement, being large to very large predators
> that are very ill-suited to taking large prey.


All this tells me is that spinosaurids had different prey preferences to 
carnosaurs, tyrannosaurs etc, with spinosaurs including a higher proportion of 
smaller prey items in their diet (small ornithopods, pterosaurs, fish).


> I would strongly suspect that, at the very least,
> the taking of aquatic prey was an important driver in
> spinosaur evolution, even if other prey types continued to be
> imporant food sources.


You could be right.  The cranial adaptations of spinosaurs might indeed have 
been geared toward improved piscivory.  But I doubt this is why spinosaurids 
got so big.


Cheers

Tim