Bird

Birds are normally feathered and flying animals. Ostriches, penguins, and emus are birds that don't fly. Robins, sparrows, and the Bald Eagle are more typical flying birds. Birds lay eggs.

Creationists' Perspective

Creationists also contend that birds being descendants of dinosaurs is unreasonable and is also not scientifically supported with any evidence.

In addition, creationists cite the current online World Book Encyclopedia which states:

"No fossil of any such birdlike reptile has yet been found."

Creationist scientist Dr. Jonathon Safarti wrote regarding dinosaurs being descendants of birds:

The same logic applies to the dinosaur-bird debate. It is perfectly in order for creationists to cite Feduccia’s devastating criticism against the idea that birds evolved ‘ground up’ from running dinosaurs (the cursorial theory). But the dino-to-bird advocates counter with equally powerful arguments against Feduccia’s ‘trees-down’ (arboreal) theory. The evidence indicates that the critics are both right — birds did not evolve either from running dinos or from tree-living mini-crocodiles. In fact, birds did not evolve from non-birds at all!

Creationists also cite the evolutionist Ernst Mayr who in 1942 stated the following:

“It must be admitted, however, that it is a considerable strain on one’s credulity to assume that finely balanced systems such as certain sense organs (the eye of vertebrates, or the bird’s feather) could be improved by random mutations."

Creationists also cite the March 2003 issue of Scientific American which stated:

"Of all the body coverings nature has designed, feathers are the most various and the most mysterious...The origin of feathers is a specific instance of the much more general question of the origin of evolutionary novelties--structures that have no clear antecedents in ancestral animals and no clear related structures (homologues) in contemporary relatives. Although evolutionary theory provides a robust explanation for the appearance of minor variations in the size and shape of creatures and their component parts, it does not yet give as much guidance for understanding the emergence of entirely new structures, including digits, limbs, eyes and feathers...."

Creationist also assert that the comparative anatomy analysis done by evolutionists comparing bird bones and dinosaur bones is flawed.

Science

Birds evolved from theropod dinosaurs over 100 million years ago. There are many well known transitional fossils to prove this. The best known (and one argued as fake by creationists despite there being 10 different fossils found at different times) is Archaeopteryx lithographica which is from the late Jurassic (about 150 million years ago) of Germany. However, Archaeopteryx fossils have been proven to be real as a result of studies. There are many other transitional fossils and more are being found.

There are many publishings in the well respected peer reviewed science journals such as Nature and Science that also agree with birds evolving from dinosaurs. Here is a publishing in Nature:

Several features, including a carinate sternum and reduced fibula, suggest that Mononychus olecranus is more closely related to modern birds than is Archaeopteryx lithographica. The two skeletons are among the best preserved fossils known of a primitive bird, and emphasize the complexity of the morphological transformation from nonavialian theropods to modern birds. The occurrence of such a primitive bird in the Late Cretaceous reflects the paucity of Mesozoic bird fossils and suggests that the early radiation of avialians is only beginning to be sampled