Have you even seen fireflies? You can't see them in any season except summer. The lights made by fireflies are probably one of the most magical things to see on a summer night. Do you wonder how fireflies make this light?
There is a part that can make light under a firetly's stomach. Fireflies take in air and use it to produce light with special cells （细胞）. Different kinds have their own special flash patterns, just like humans have different languages. They use these flash patterns to find other members of their group.
Fireflies mainly use the light to get friends' attention. The males （雄性） fly around while turning their lights on and off, hoping to get the attention of a female. They try to flash very quickly, because the faster males flash, the more attention they can get from females. Fireflies also use the light to make their enemies scared.
If you haven't seen many fireflies lately, you are not alone. The number of fireflies may bed ropping because of some reasons, such as light pollution and chemical medicine use. Another important reason is that fireflies' living places are destroyed by humans. Luckily, Chinese scientists recently found three new firefly kinds in Yunnan. Yunnan might have the right environment for these magical insects to live in.
①Spring ②Summer ③Autumn ④Winter
