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Have you ever walked into a grocery store and wondered where all the varieties of apples came from? You might find SnapDragon, Pixie Crunch, Cosmic Crisp, Jazz, or Ambrosia next to the more familiar Red Delicious and Granny Smith. So why are there so many types? Theresa Doud describes the ins and outs of breeding apples.

Lesson by Theresa Doud, animation by Adriatic Animation.