原文已被隐藏，你可用 快捷键 - 或点击 显示原文 按钮来查看原文
第一段
1 .Listen to part of a lecture in a Botany class.
该句暂无译文！
第二段
1 .When we talk about pollination ecology, we're talking about the relationship between a plant and its pollinator.
该句暂无译文！
2 .From the plant's perspective, the ideal pollinator is an animal that is under-fed, ready to eat and in a hurry.
该句暂无译文！
3 .The pollinator, on the other hand, wants to remain well-fed with as little effort as possible.
该句暂无译文！
4 .These factors help drive the evolution of plants and their pollinators, both of which depend on this balanced and delicate relationship.
该句暂无译文！
5 .Sometimes only certain insects or birds can pollinate certain plants species.
该句暂无译文！
6 .So, to really understand pollination ecology, both the flower and its pollinators must be studied.
该句暂无译文！
7 .Let's start with flowers.
该句暂无译文！
第三段
1 .There are several important factors associated with pollination: when and how often a plant flowers, how long the flowering cycle lasts, and the number of flowers that open at the same time.
该句暂无译文！
2 .For example, flowering may coincide with the migration of a certain animal species that pollinates the plant or producing many flowers at once may increase the number of pollinators a plant attracts.
该句暂无译文！
3 .Other characteristics of the flowers are also important: features such as color, scent and shape attract pollinators as does the reward in the flower, the pollen or the nectar that feeds the pollinator.
该句暂无译文！
第四段
1 .For example, flowers that attract bats tend to be green- or cream-colored, because visibility isn't important.
该句暂无译文！
2 .Bats are practically blind, remember.
该句暂无译文！
3 .And these flowers bloom at night when the bats are active.
该句暂无译文！
4 .Now, there's a flower in the Amazon rainforest called a royal water lily and the characteristics of its flowers change during the pollination process.
该句暂无译文！
5 .The royal water lily uses color, temperature and scent to attract the beetles that pollinate it.
该句暂无译文！
6 .When the flowers of the royal water lily first open up, when they first bloom, they're white, they also emit a strong odor and their temperature rises.
该句暂无译文！
第五段
1 .Producing heat serves two purposes: it magnifies the scent of the flower and it helps the beetles maintain their body temperature.
该句暂无译文！
2 .When a beetle arrives at the flower, the flower closes around it for about 24 hours so that the beetle becomes covered with pollen.
该句暂无译文！
3 .Then when the flower opens, its color changes to red and it cools down.
该句暂无译文！
4 .When the beetle flies out, it carries the pollen to a different heated, white, fragrant flower.
该句暂无译文！
5 .As you can see plants go to a lot of trouble to attract attention.
该句暂无译文！
6 .So what kind of attention are they attracting and why?
该句暂无译文！
第六段
1 .Well, sometimes flowers provide shelter for insects, a place to lay eggs, for instance, but usually the attraction is food, nectar and pollen.
该句暂无译文！
2 .Nectar's mainly a sugar solution while pollen is a grain made up of part of the plant's cell structure.
该句暂无译文！
3 .In both nectar and pollen production, quality and quantity vary over time but they're always related to the needs of the pollinator.
该句暂无译文！
4 .You can see that the relationship between pollinators and plants are delicate.
该句暂无译文！
5 .So any number of factors can disturb them.
该句暂无译文！
第七段
1 .Uh, human development is one and agriculture is generally believed to be the most harmful.
该句暂无译文！
2 .It can fragment habitats in a variety of ways reducing the number of pollinators which, in turn, may reduce the number or size of the flowers which, of course, affect the animals that feed on them.
该句暂无译文！
3 .Uh, exotic plant species not native to the area can move in and compete.
该句暂无译文！
4 .Even bees brought in to pollinate crops can alter natural pollen dispersal system of rainforest plants.
该句暂无译文！
第八段
1 .On the other hand, recent studies have shown that the disruption of one aspect of the pollination cycle doesn't usually lead to the extinction of other species.
该句暂无译文！
2 .It turns out that plant-pollinator relationships are more adaptable to change than we thought.
该句暂无译文！
3 .So, really, it's hard to know just how agriculture affects the pollination of plants.
该句暂无译文！