Tangle-web spiders may not be the biggest or strongest arachnids on the block, but they’re master string pullers. A new study reveals the half dollar–size animals are able to nab prey 50 times their weight by skillfully manipulating the threads of their webs.
Researchers observed three species of these common spiders (members of the Theridiidae family) ensnaring cockroaches of varying sizes in a laboratory. The arachnids captured these relatively giant victims by keeping sticky threads hanging low in the web. But the researchers didn’t know the mechanisms that allow them to lift the heavy prey up.
In the experiments, the team found that the spiders go up and down the web taking a few threads of silk that are kept taut (like a stretched elastic) and attaching them to the stuck prey. The elastic energy in the threads works like a pulley, making it much easier for the spiders to lift heavy loads, the team reports today in the Journal of the Royal Society Interface.
As such, the arachnids are able to grab everything from bugs to lizards to mice—despite not having the natural strength to do so. Take that, Spider-Man.
Source: Science Mag