Birds are not the only animals that move and make noise. Male wolf spiders will sometimes lay down a beat for 45 minutes to win over a female.
The male wolf spiders put on quite the show by flexing their appendages, shaking their abdomens, and tapping their foreleg. The act should be more elaborate.
The Schizocosa stridulans wolf spider is found in North America and new research has found that males that drum up the most complex rhythms are the most popular with the spider ladies.
It is more than the good vibrations that move them. Even though it was obvious that the male would look to predators, the female chose to ignore them.
It remains an open question as to why females are more likely to accept males with more complex displays.
Despite higher costs of increased signal complexity, our data shows that S. stridulans males can and will change their signal complexity.
Researchers filmed wolf spiders to see how they reacted to each other. The dates were recorded on strips of filter paper, which allowed the researchers to record the animals' delicate vibrations.
The female spider was the first to arrive, and as she waited for her suitor, she unfurled a string of silk laden with pheromones.
The spiders were allowed to interact for up to 20 minutes when the male arrived.
Men copulated more and faster if they produced complex signals in their courting.
This meant mixing up the transitions between the sounds of a nail on a rough surface and the clatter of high heels on a linoleum floor.
The signals are felt in the form of vibrations by the female spider.
In cases where the female looked particularly fertile, successful male spiders stepped up their transitions and began making sounds.
The males are altering their signaling complexity according to feedback from the females.
People who work on other animal groups are often surprised when they see stories of spiders engaging in sophisticated behaviors.
We have found this in several studies, and it shows that spiders are just as smart as any other animal when it comes to communication.
In studies on other species of wolf spiders, researchers have found that males that use different types of signals are more successful at sex than males that only use visual signals.
The complex setlist seems to be a classic example of sexual selection, where female choice helps sculpt more and more elaborate means for sex.
The taps and shakes of the male wolf spider are striking a cord with females, but whether or not these signals convey something deeper is unknown.
Male wolf spiders were not more successful at winning over a female if they were larger in size. Maybe the complexity of taps and shakes is telling the female how fit the male is.
Hebets says females aren't necessarily looking for the biggest male or the strongest male.
There is a debate about sexual selection in the animal kingdom. Is it a sign of high-quality mates or is it simply a case of female aesthetic preference?
Maybe the wolf spider can help us figure it out.
The study was published in a journal.