Spiders have begun to sing, looking for love

We already know that a wide variety of animals uses sound to communicate.
Then again, there are thousands of animal species that communicate through another very similar means: vibrations.
Wolf spiders (Gladicosa gulosa), differently from the majority of spiders, create audible sounds using vibration communication. And, guess why?
It’s all about love!
Prof. Alexander Sweger and Prof. George Uetz from the University of Cincinnati recorded the sound of love of wolf spider Gladicosa gulosa.
"I decided I wanted to find out whether this species using airborne sound to communicate," Mr. Sweger told BBC News.
They then recorded back the sound to female spiders and they discovered that the sound of love works if the spiders were on leaf-like surfaces that vibrated easily.
Generally, spiders do not possess structures for hearing sound. The “purring” wolf spider (Gladicosa gulosa) may be a unique exception to this assumption.
Spiders have special sensory organs in their legs, Prof Uetz explained. "They're called sensillae; they're sort of in their knees - that's how they hear."
So, it seems that spiders have adapted a very early evolution of a primitive sound-based communication singing through the forest floor looking for love.
Listen to a recording of this sound here .