科学美国人60秒 SSS Pollinators Shape Plants to Their Preference-英语课

时间：2018-12-24 作者：英语课 分类：2017年Scientific American(三)月

英语课

Pollinators Shape Plants to Their Preference 我的进化来自你的偏好

Honeybees are the charismatic microfauna of the pollination 1 world. But flies, bumblebees, butterflies and moths—they all pollinate, too. With varying degrees of success. The poorer ones are technically 2 referred to as 'inefficient 3 pollinators.' "Those that do visit but transfer very little pollen 4 in their visit." Florian Schiestl, an evolutionary 5 biologist at the University of Zurich.

蜜蜂在授粉界具有非凡的魅力。但是苍蝇、大黄蜂、蝴蝶以及飞蛾——它们都可以授粉。不过授粉成功率不同。技术水平较低的称为“低效授粉者”。它们在旅途中也可以授粉，不过传递的花粉量较少。Florian Schiestl是苏黎世大学的进化生物学家。

Schiestl and his colleague grew field mustard plants, and exposed them to two types of pollinators: efficient bumblebees and inefficient hoverflies. After just 11 generations, they found that the plants visited by bumblebees were taller, twice as fragrant 6, and reflected more UV light—a visual signal for bees. And those factors made the progeny 7 even more attractive to bumblebees at the end of the experiment: a sign the plants had adapted to their pollinators' preferences.

Schiestl和同事种植了荠菜，并让其可以接触两种授粉者：高效的大黄蜂和低效的花虻。这些植物经过11代后，研究人员发现，由大黄蜂授粉的荠菜，其高度增加，芳香度加倍，同时可以反射更多的紫外线——这种紫外线对于蜜蜂是一种视觉信号。所有这些因素使得在实验最后，这部分荠菜的后代对于大黄蜂更具吸引力：植物使自己适应了授粉者的偏好。

But the plants that got a fly-by from the flies? They grew shorter. Less fragrant. And actually adapted to do more self-pollination. Because hoverflies are lousy pollinators. The study is in the journal Nature Communications.

但是对于只有苍蝇飞过的荠菜呢?这些植物变得更矮，同时芳香度降低。实际上，是适应了自我授粉。因为花虻是糟糕的传粉者。该研究结果发表在《自然通讯》杂志上。

So with honeybees in peril 8, what happens if we lose them? “This will trigger an evolutionary response in the plants. For example, if flies take over as more important pollinators, as they used to be in the past, then very likely we'll have some evolutionary change going on."

蜜蜂现在也面临危险，如果没有了蜜蜂呢?“这将会引发植物的进化反应。”例如，苍蝇将会像过去一样，成为重要的授粉者，然后，可能还有有其他的进化改变。

And if the change is self-pollination, that could be trouble. "Self-pollination leads to reduction of genetic 9 variability in the population, and this can be a problem for the plants, because they have a reduced ability to evolve resistance against diseases." Meaning that if we lose the pollinators, it’s the plants' genomes that may go to seed.

如果导致植物自我授粉，那么就会造成麻烦。“自花授粉会导致该品种的遗传多样性减少，这对于植物来说是个麻烦，因为它们抵抗疾病的能力就会降低。”也就是说，如果我们失去了授粉者，那么，植物的基因也会退化。