Re: Sinosauropteryx filament melanosomes challenged

[vultur-10@neo.tamu.edu]

Using Reptilia for Lepidosauria or Squamata has the same problem -- it's just 
as unnatural to have it exclude turtles and crocs as it is to have it include 
birds.

Since there's no clade "turtles + snakes + lizards + crocodiles + tuataras" 
(all the scaly, egg-laying cold-blooded animals) to the exclusion of birds, 
which is what 'reptile' has meant for at least a couple centuries, using 
Reptilia as a clade *at all* just seems designed to confuse.

Restricting 'fish' to Actinopterygii similarly; trying to change the use of 
common names doesn't have much chance. Furthermore, even if we could do it 
unambiguously, we already HAVE a word for Actinopterygii -- we would lose any 
word for what people call 'fish' now -- 'non-tetrapod vertebrates'? 

Why mess with the language to make clades the only groups easy to refer to? 
There ARE meaningful paraphyletic groups, after all - those 'left behind' after 
the development of a really big innovation (vertebrates-minus-tetrapods, or 
tetrapods-minus-amniotes, or apes-minus-humans) -- in all three cases, the 
evolutionary innovation (land life; amniote egg; human brain & technological 
ability) made a colossal ecological difference, opening up whole new 
possibilities.

----- Original Message -----
From: "David Marjanovic" <david.marjanovic@gmx.at>
To: "DML" <dinosaur@usc.edu>
Sent: Tuesday, December 7, 2010 5:58:24 AM GMT -06:00 US/Canada Central
Subject: Re: Sinosauropteryx filament melanosomes challenged

>  The way the term actually gets used, in reality, equates to
>  'ectothermic amniote' (I say ectothermic rather than poikilothermic
>  because of hummingbird torpor and such). Trying to make it a clade
>  (and thus including birds) just confuses people.

Indeed.

>  But there really isn't any gain in getting rid of the word entirely,
>  either; having to talk about "lepidosaurs, crocodilians, and
>  chelonians" would be a pain.

Getting rid of it is the only way to make clear that it isn't a clade.

>  The formal classification Reptilia should just go away -- presuming
>  we're using a system where monophyly is required. But the informal
>  term 'reptiles' is still useful.

The only way to possibly save it is what Joseph T. Collins (aka "Center 
for North American Herpetology") does: he uses it for either 
"lepidosaurs" or "squamates" (same thing for a neontologist in North 
America, so I can't tell). He now routinely writes about "the turtles, 
reptiles, and crocodilians of North America" or "the turtles and 
reptiles of Kansas". But why do that when "squamate" (and "lepidosaur") 
is already available?

>  Same for 'fish' (Class Pisces is pretty much dead, but we can still
>  talk about fish).

But should we?

My doctoral supervisor, Michel Laurin, is notorious for having banned 
the word "fish" (in several languages) from his own usage and that of 
anybody he can influence. In his previous department, there was a 
tradition that, every year before Christmas, the whole department had a 
dinner in a restaurant. One year, he says, they were served ray wings. 
The organizer said "oh no, anything but this!" It turned out she had 
ordered "fish" and got "fish". Michel immediately pointed out that they 
wouldn't have got chondrichthyan if she had ordered actinopterygian or 
teleost, which was what she actually wanted.

Ray wings, for those who haven't had the questionable pleasure, are 
fibrous and slimy at the same time; not to everyone's taste. It is 
immediately obvious that teleost is much more similar to amniote meat.

I hope the word "fish" will one day be restricted to "actinopterygian". 
I think a slow trend towards this already exists.