SYDNEY, June 15 (Xinhua) -- New Australian research on Thursday uncovered that European ground-spiders ambush and fire super silk instead of waiting for unlucky prey to get caught in their trap.
"I read that these spiders (the Drassodex heeri) may try to take on larger prey," author of the study Jonas Wolff told Xinhua Thursday.
"They eat all kinds of insects and ants, but what is surprising is that they even attack large spiders, even larger than themselves, but no one had ever looked at it with modern techniques like scanning it with unitron microscopes."
According to Wolff, spiders usually try to avoid such dangerous prey items, "but that's not the case for ground spiders and this is because they have this particular strategy to lure it down on the ground and immobilize it."
In order to conquer larger targets, the key is a special type of silk called piriform, which "most spiders only produce when they need to securely anchor a structural thread," Wolff said.
The researcher realized that the piriform silk-producing glands of ground spiders were both larger and fewer than other web-spinning spiders.
"The core message of our research is that we found a particular example of a biological trade off," Wolf explained.
Although ground spiders are unable to spin the densely packed webs because of their enlarged piriform silk glands, they are able to eject a thick layer of glue at high speed in order to overwhelm their prey and anchor them to the ground.
To test the theory, the researcher pit the ground-spider against a number of different web-spinning house-spiders, in what could be considered a series of spider boxing matches.
"We set up a high speed video camera, because the action happens very quick and you don't really see the silk coming out, so we also needed to use a special illumination technique," Wolff said.
"This is the first time someone has actually looked at this from a biomechanical point of view and this can give us great insight into broader applications of their silk."