An idea that will likely make the blood of spider phobias clot in their veins: Engineers at Rice University in America have found a way to reposition the limbs of dead spiders (see video above). With these “zombie spiders” it is even possible to grab small delicate parts that are heavier than the animal itself.
“We were rearranging things in the lab and saw a spider curled up on the edge of the aisle,” explains Faye Yap, a doctoral student at Rice University. “We were very curious as to why spiders curl up after they die.”
Perfect Greifarme
A quick search yielded the answer: “Spiders don’t have antagonistic muscle pairs like the biceps and triceps in humans,” Yap says. “They only have flexors, which allows them to curl their legs and extend outwards with hydraulic pressure. When they die, they lose the ability to actively exert pressure on their bodies. That’s why they curl up.”
“Coincidentally, after its death, the spider has the perfect architecture for small, naturally formed claws,” added research colleague Daniel Preston.
A little busy and the spiders move
Unlike humans and other mammals, which move their limbs by synchronizing opposing muscles, spiders use hydraulics. A chamber near the head contracts to channel blood to the extremities, forcing them to stretch. When the pressure is released, the legs contract.
Internal valves in the spiders’ hydraulic chamber, the prosoma, allow them to operate each leg individually. “The dead spider doesn’t control those valves,” he said. “They are all open. That worked for us in this study because it allowed us to check all the legs at the same time.”
Setting up a spider grab was quite easy. Yap stuck a needle into the prosoma chamber and secured it with a dollop of superglue. The other end of the needle was attached to one of the lab’s test benches or a hand syringe, which released a small amount of air to activate the legs almost immediately.
Lifting more than your own body weight
The carcasses used in Preston’s lab were wolf spiders, and tests showed they were reliably capable of lifting more than 130 percent of their own body weight — and sometimes much more. They let the claws manipulate a circuit board, move objects and even lift another spider.
Researchers found that smaller spiders can carry heavier loads compared to their size. Conversely, the bigger the spin, the less load it can bear compared to its own body weight. So there are many applications for this technology – for example in the assembly of microelectronics or for catching smaller insects that are naturally well camouflaged, the researchers said.
Source: Krone
I’m Wayne Wickman, a professional journalist and author for Today Times Live. My specialty is covering global news and current events, offering readers a unique perspective on the world’s most pressing issues. I’m passionate about storytelling and helping people stay informed on the goings-on of our planet.
