Environmental Philosophy has a call for papers for an upcoming issue which includes environmental aesthetics. I'm thinking about sending them something about passing aesthetic judgments on species. I'm not really sure what I want to say on the subject, other than that people do it, and that it is kind of a weird thing to do.
In some ways the aesthetic evaluation of species is like dog-show aesthetics. You are after all, judging the beauty of an animal. But in a dog show, you judge an individual animal for how well it realizes the type. But when you judge whole species, you don't look at how they realize the higher taxon they belong to. Carlson says you judge whale you have to know it is a mammal, but you don't judge it for how well it realizes mammalness.
On a related note, this is the best video for TMBG's Mammal I have bumped into so far. A lot of people seem to try them, because the song lends itself to stock images so easily. I still haven't found one I'm perfectly in love with yet.