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Once male and female cells have come together and developed into offspring, they must be given a good start The animal mother can search out a promising location and deposit her young there But plants need help If the seeds simply dropped from the plant to the ground, they would have to compete with each other and with their overshadowing parent for sunlight and soil minerals So successful plant families have developed mechanisms for dispersing their seeds far and wide These mechanisms include seed containers that pop open and propel their contents in all directions, seed appendages that catch the wind or the fur of a passing animal — and structures that hitch a ride inside passersby Fruits are plant organs that actually invite animals to eat them, so that the animals will carry their seeds away, and often pass them through their digestive system and deposit them in a nourishing pile of manure (The seeds escape destruction in various ways, among them by being large and armored, or tiny and easily spilled, or poisonous.) So, unlike the rest of the plant, fruit is meant to be eaten This is why its taste, odor, and texture are so appealing to our animal senses But the invitation to eat must be delayed until the seeds are mature and viable This is the purpose of the changes in color, texture, and flavor that we call ripening Leaves, roots, stalks can be eaten at any time, generally the earlier the tenderer But we must wait for fruit to signal that it is ready to be eaten The details of ripening are described in chapter 7 (p 350) Our Evolutionary Partners Like us, most of our food plants are relative newcomers to the earth Life arose about 4 billion years ago, but flowering plants have been around for only about 200 million years, and dominant for the last 50 million An even more recent development is the “herbaceous” habit of life ...among them by being large and armored, or tiny and easily spilled, or poisonous.) So, unlike the rest of the plant, fruit is meant to be eaten This is why its taste, odor, and texture are so appealing to our animal... and texture are so appealing to our animal senses But the invitation to eat must be delayed until the seeds are mature and viable This is the purpose of the changes in color, texture, and flavor that we call ripening... generally the earlier the tenderer But we must wait for fruit to signal that it is ready to be eaten The details of ripening are described in chapter 7 (p 350) Our Evolutionary Partners Like us, most of
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