Nature
PUBLISHED
If anyone has ever thought that their car was irresistible to spiders, well you might be onto something.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.An arachnologist from Queensland Museum, Brisbane, has stumbled across a novel way of catching spiders: simply leave your car idling, and let the eight-legged critters come to you. He says that the vibrations generated by the rumbling car agitate the spiders to such a degree that, rather than running away from the source, they actually move towards it.
In fact, so successful is this method that Dr Robert Raven says that it in certain situations it can be much more effective when sampling spiders than the traditional techniques such as by eye, trap, or spraying. If the car is parked on a soft surface, allowing the vibrations to travel further, then it can draw the arachnids out of a whole host of different hiding spots, from the bark in trees to holes in the ground, giving the biologist a much more complete inventory of their diversity in that environment.
But fear not, all you arachnophobes out there. Not all cars will have such a dramatic effect. “I deliberately got an old diesel in order to get this effect,” Dr Raven told ABC News. “Because the new ones are too sweet and smooth. 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.”
This could, however, help explain why for some it seems that their old bangers are a spider magnet: Because they are.
Dr Raven suspects that the reason might be to do with the fact that in general, spiders tend to communicate through vibrations. In the animal kingdom, this is in no way unusual as a wide range of animals send messages in this form, from the low infrasonic rumblings of elephants to the waggle dance of bees.
The noise of the rumblings from the car are likely to be deafening to a tiny spider that normally chats away through these vibrations, and so rather than running from the source, they actually flock towards in search of the “zero point” between the four wheels. Like the eye of a storm, this is probably a patch of calm for the arachnids.
This might well be the reason that some of you out there keep finding spiders in your car. There is one very easy piece of advice if you think that you might be among them: just turn your engine off if you’re not traveling.
