Re: Thanks to everyone

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

> I've decided that I'm going to tell them that "dinosaur" does not mean any 
> prehistoric animal, but a specific group unified by several small skeletal 
> details (for example, the fused vertebrae mentioned on the website of one 
> of the posters here) that all dinosaurs inherited from a common ancestor 
> about 230 million years ago. I will tell them that any descendent of that 
> ancestor is a true dinosaur.

Rather make it the other way around: that ancestor, and all its descendants, 
are dinosaurs; which animals are descendants and which are not can be 
_recognized_ by those features. Emphasize the distinction between what _is_ 
and how we _know_ about it.