【英语时差8,16】成熟的水果(下)(在线收听

Plants attract fruit eaters–or “frugivores”–by packing valuable resources into their fruits like sugar and water or important nutrients such as carotenoids, vitamins and minerals. Plants often target specific animals that will give their seeds the best chances for germination, and discourage or repel animals that won’t. Plants that want to attract birds rather than mammals might produce thorns or have fruits that taste unpalatable to most mammals but tasty to birds. Plants that want to repel birds but attract mammals might have fruits with thicker, tougher outer skins. Don’t forget that selective breeding by humans has dramatically changed many fruits from their wild state, often resulting in larger, sweeter fruits with fewer seeds.
 
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