你见过会叫的蜘蛛吗?
These spiders can purr
这种蜘蛛能发出低沉的声音Wolves howl to let others know that they're around - and maybe even that they are looking for a mate. But not the wolf spider known as Gladicosa gulosa. It makes a kind of a purr. It's quite a trick for guys of this species. And that's because it's not clear that the target of their attentions can actually hear a purr. A female may just feel the effects of that sound as vibrations in her feet. But even that may not happen unless both he and she are standing on the right surface.
狼通过嚎叫的方式告知周围它们的存在，甚至还会用这种方式求偶。但一种被称为Gladicosa gulosa的狼蛛则不然，它们会发出一种低沉的咕噜声，对于这种生物来说这样做也的确算得上是一项独门秘技。因为他们所关注的目标实际上能否听见其低鸣尚不清楚，或许雌蜘蛛只能感觉到雄蜘蛛发出声音时在它们脚底下产生的振动，可是当他们没有站在合适的平面上时雌蛛可能连振动都感觉不到。
How the spider purrs
蜘蛛如何发出低鸣声？
At mating time, male wolf spiders try to catch a female's attention by creating "persuasive" vibrations, Sweger says. They strum one structure on their body against another - somewhat as a cricket does - to impress the gals. Getting the message right can be a matter of life and death to the guy who's doing the wooing. If the female isn't totally convinced that he's the "one," it could be worse than just being rejected, Sweger explains. "She could eat him." About one out of every five male wolf spiders will be eaten by the female he had been wooing. But the guys who prove suitably persuasive will get to mate - and live to tell the tale.
求偶时雄性狼蛛会使出浑身解数用"劝诱"的振动方式吸引雌性狼蛛的注意，他们用身体的一部分拍打另一部分发出震动声（就像蟋蟀一样），而后给雌蜘蛛留下印象。Sweger表示能否正确收到求爱信息关系着求爱者的性命，如果雌蜘蛛没能被完全说服他就其 "真命天子"，那么雄蜘蛛的情况有可能比被拒绝还要糟糕，他可能会被她吃掉。这并不稀奇，因为每五个雌性狼蛛中就有一个被他们的所追求的另一半吃掉。但如果事实证明雄蜘蛛的确有劝诱能力，那么他们最终将会得到交配的机会，并向配偶讲述他们悲惨的"浪漫际遇"。Purring spiders "are using the same vibratory tactics as every other wolf spider in North America. More or less," Sweger says. "They're using the same structures. And they're making vibrations."But the scientists showed that compared to the wooing vibrations made by other wolf spiders, those by Gladicosa gulosa are far stronger.
Swege称在北美这种能发出低吟声的蜘蛛或多或少使用的都是和所有其他狼蛛一样的振动技巧。它们使用的是同样的身体结构来产生振动。但科学家表示，与其他发出求爱振动信号的狼蛛相比，这种名为Gladicosa gulosa的狼蛛的振动更加强烈。Sweger discovered something else as well. When a purring spider was on a surface that is good at conducting vibrations, such as leaves, an audible sound was produced.
Sweger还发现了其他一些东西。当一只低吟的狼蛛处在更有利于传导振动的位置，比如说树叶上时它们会发声音。If a person is within a meter of the courting spiders, they can actually hear the sound. "It's very soft, but when we're out in the field, you can hear them," Sweger says. The sound, he explains, is a bit like a "little strumming chirp" or a "soft rattle or purr." (You can judge for yourself.)
Sweger表示当一个人距离一只正求偶的狼蛛仅一米时，他会听到这种声音，和柔和。但当我们在野外时，你也会听到它的声音. 这种声音类似于有节奏的唧唧声，或者是那种柔和的咯咯声、咕噜咕噜的声音等等（这就得靠你自己判断了）。
