While checking out the fresh produce at our community's marvelous Outdoor Market, I overheard a conversation between two mothers. They wondered why their children refuse to eat some vegetables that most adults like—and they both admitted that they had similarly disliked the same foods when they were children.

I didn't consider it appropriate to intrude into their conversation, but since they raised a common parental concern, I'll respond to it here.

Animals have legs, wings or fins that allow them to seek food and escape predators. Conversely, immobile plants have roots that anchor them to one location. Their survival thus depends on leaves and roots that absorb the available sunlight, water, and nutrients they need—and on biological strategies that discourage the predatory nibbling of herbivores.