A Queensland researcher has found that the vibrations given off by certain cars can irritate spiders so much that they can’t help but rush towards the offending source.
Dr Robert Raven is an arachnologist with the Queensland Museum and has witnessed every arachnophobe’s worst nightmare first hand: Floods of spiders running towards his idling car.
Spiders are very sensitive to vibrations, so something like an old 4WD engine has the ability to overstimulate their senses to the point where normal self-preservation instincts are forgotten and they rush towards the potential danger.
“When you let one of these old diesels idle for example on sand on a hot day, spiders that normally will not move in the daylight are running towards the car. They are highly disturbed,” Dr Raven told the ABC.
“I deliberately got an old diesel in order to get this effect. Because the new ones are too sweet and smooth.”
He said it is likely that the spiders are running towards the “zero point” between the car’s wheels where, much like the eye of a storm, they could find relief from the distressing vibrations.
An idling car is such an effective way of getting spiders to emerge from their hiding spots that Dr Raven said he often uses it as a method of capturing species to study.
“We get higher species numbers by that method alone, than we do by any other single method of collecting by eye, by trap, by spraying anything,” he said.
“This is the best way, because you get things coming out from holes in the ground, you get them coming out from under bark in the tree, coming down the tree.”
According to Dr Raven it is a pretty common occurrence, whether we realise it or not.
One horrified mother was ready to sue her son’s school after experiencing this phenomenon.
The woman told Dr Raven that she had found a wolf spider in her son’s school bag, to which he asked: “Do you own a 4WD diesel? … Did you leave it idling for a little while this morning?”
Unsurprisingly the woman answered yes to both questions.
Her son’s backpack had been left on the ground by the idling car, so in the spider’s vibration-induced panic it ran into the bag and ultimately hitched a ride to school.
Moral of the story: If you own a 4WD try not to let it idle for long, unless you want a car full of angry arachnids.