評論
打印
Here’s how Knab explained it: males gather around some landmark—a cornstalk, perhaps the head of an unsuspecting human–and wait for eligible females. When a female enters the swarm, the males immediately pick up her flight tone, which is different from theirs. Coupled with one lucky guy, she flies to some protected place to mate. After their interlude, the female goes to lay her eggs, but the male returns to the swarm, on the outside chance that he’ll get lucky once more. That’s why Knab netted so many more males than females. Sometimes, these gatherings get quite large. In Germany, in 1807, people saw a huge cloud of smoke billowing over a church. So they called in the fire brigade, only to realize that the dark cloud was actually a swarm of gnats who’d picked the church steeple as their rendezvous.
下面是Knab對這一現象的解釋：雄性聚集在周圍的一些地界標上——比如玉米秸稈，也許是不知情的人的頭部——等待合適的雌性。當雌性進入昆蟲群時，雄性的飛行狀況馬上變成和雌性的一樣，這和雄性本來的飛行是不同的。和一個幸運的雄性配對后，雌性會飛到受保護的地方進行交配。這段插曲過后，雌性去下蛋，但雄性會飛回原地，它還有極小的機會再次得到配偶。這就是為什么Knab捕到的雄性蚊子遠多于雌性。有時，這些昆蟲聚集會很大。1807年在德國，人們看到了滾滾濃煙在教堂上翻滾。因此，他們給消防大隊打電話，后才才弄白烏云實際上是一大群飛蟲，它們將教堂的尖頂作為約會地點。
