Spider deceived

29december2010
Source: scientias.nl
Spiders use their web to catch insects. But now an insect has been discovered that reverses the roles. This insect makes the spider's web vibrate and thus imitates prey. The spider that responds to the vibration is stung and eaten.
The insect (Stenolemus bituberus) belongs to the class of hemiptera, which also includes bugs, aphids and cicadas. It uses the hunting method of the spiders. Spiders track the insects that have been caught in the web on the basis of vibrations. The Stenolemus bituberus uses its front legs to make the web vibrate. The spider that arrives at this call is caught between the front legs of the insect and is stung. The spider quickly dies thereafter.
The vibrations that the Stenolemus bituberus creates are the same as those produced by insects that are truly caught in the web. Researchers investigated this by hanging over a spider’s web for hours. The insects move very carefully in the web. The trick does not always work however. Also the Stenolemus sometimes disappears into the spider’s stomach. And yet the researchers are full of admiration for the insect. They find it unbelievable that an animal that is usually considered the spider’s food has managed to control the predator’s behaviour in this way.