[VadeRetro]

Hatchling frogs (an amphibian) look like fish (an earlier-appearing and more primitive phylum).

Got my cut-and-paste going at the expense of accuracy. Chordata is a phylum which Amphioxus, fish, and frogs share.

[PatrickHenry]

Chordata is a phylum which Amphioxus, fish, and frogs share.

Next thing you'll be telling us is that all those different kinds of chordates got their spinal cords because of common descent. Give it up!
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