It is this way in the case of the Archaeopteryx . The Archaeopteryx is a fossil that evolutionists, although not the most knowledgeable and experienced evolutionists, will always point towards when asked for proof of any missing link. This famous fossil is what they call a transitionary form from the reptile to the bird. A exceptionally preserved fossil, Archaeopteryx is very obvious in what features the organism possessed. Features which only belong to birds, including feathers, and a beak, and many other structures of a bird.
Archaeopteryx also possesses features evolutionists say only belong to animals which are reptiles.
These include teeth, claws, and some bone structure. In all reality, however, Archaeopteryx is a pure bird. Quite correct, except that Archy does not have a beak. It has a toothed mouth, like birds don't, although reptiles do. We have to draw the line somewhere, and science has arbitrarily decreed that anything with feathers is a bird.