<p>^Stop being a know-it-all jerk. SAT/AP Biology does not require you to know the exact time sea stars (not starfish) evolved. They want you to see that it is an echinoderm and echinoderms existed BEFORE any type of vertebrate.
Sea Star, Shark, Dinosaur, Bird, Whale.
Echinoderm, chondrichthyes, Reptilia, Aves, Mammalia.</p>