Neither. Birds are their own class of animal.
A whale. Amphibious means "capable of functioning on land or in water". Whales are not amphibious. Frogs are amphibious.
The Bosco Dictiosaur was the only documinted animal with both mammal and amphibious jeans. 98% mammal, 2% amphibious.
yes
There isn't a mammal-bird.
No. Whether it is tropical or not, no bird is a mammal.
There is no such thing. No bird is or ever was a mammal.
No. A budgerigar (budgie) or parakeet is a bird, not a mammal.
A mammal.
mammal
Bird
The Kea is not a mammal. Its a bird.
A chickadee is not a mammal. It is a bird.