Spiders have special sensory organs in their legs that allow them to detect the presence of a friend or foe. It’s how they “hear” their prey coming towards their trap. But, these vibrations aren’t only used for detecting what might be their next meal. One species, known as the purring wolf spider (Gladicosa gulosa), use the vibrations to woo a potential mate with their love song.
In a recent study researchers put a male and female purring wolf spider in separate cages. They wanted to see if the spiders would react from just the sound the male makes when he’s singing to a female. They first placed specific scent cues to trigger the male spider to start purring. The male spider is able to make this sound by dragging a comb-like “stridulatory organ” across whatever surface they are standing on.
The researchers then played only the sound of the male spider’s purring to the female, leaving her on material that would not vibrate in response to the sound. But, the male spider could not quite make the proper sound, and the female did not react to the simple auditory stimulation. So, the researchers tried this experiment again, but this time they placed each spider on leaf-like surfaces. Voila! It did the trick!
They found that the purring sound the male spider was making was magnified and turned into airborne sound. This vibration helps to carry the serenade over to the female, who then feels the vibration as well as hears the love serenade being sung to her. The vibration of the leaves is crucial for the song to travel to the female spider. We then have the song traveling from leaf to leaf through vibration until it reaches the intended audience. So spiders are romantic when you think about it, sending their love songs across the distance to woo the female spider they have the hots for. It makes my heart melt.
Did you know that spiders sang love songs to their mates? Isn’t that awfully romantic for what we usually think of as a cold calculating insect?