perching bird vs animal order

perching bird and animal order both are nouns.

Word	Noun	Adjective	Verb	Adverb
perching bird	Yes	No	No	No
animal order	Yes	No	No	No

As nouns, animal order is a hypernym of perching bird; that is, animal order is a word with a broader meaning than perching bird:

perching bird: a bird with feet adapted for perching (as on tree branches); this order is now generally abandoned by taxonomists
animal order: the order of animals

perching bird (noun)	animal order (noun)
a bird with feet adapted for perching (as on tree branches); this order is now generally abandoned by taxonomists	the order of animals