Being aquatic was Re: Obdurodon (was Re: Coronosaurus [...])

[David Marjanovic <david.marjanovic@gmx.at>]

> > Preponderance? We have  Gansus and Hesperornithes showing aquatic
>> adaptations. Yanornis sometimes ate fish (but so did
>> Confuciusornis, and it's not considered aquatic)
>
> We also know that _Baryonyx_ and _Scipionyx_ ate fish. These
> non-avian theropods also lack any obvious aquatic adaptations.

They do have adaptations to catching fish. "Aquatic" is usually taken to 
mean "living in water", and *B.* and *S.* didn't live in water.

> By contrast, although there are  putative aquatic enantiornitheans,
> they are exceptional in this regard (among Enantiornithes)

Longipterygidae was quite diverse, though.

> and many more show highly  refined perching abilities suggesting they
> were specialized arborealists.

That's not mutually exclusive with being a specialized piscivore, as 
kingfishers demonstrate today (never mind fish-eating eagles and owls).