Live Science: Chris Pires, an evolutionary biologist who studies crop science at Colorado State University, calls these veggies “the dogs of the plant world.” All pet dogs (Canis lupus familiaris) are the same species, domesticated from wolves (Canis lupus), and they come in different varieties, or breeds. Similarly, broccoli, cauliflower, kale and the other aforementioned vegetables were also domesticated from the same species, B. oleracea.

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