The web of the Darwin's bark spider (Caerostris darwini), can span some square feet (2.8 square meters) and is attached to each riverbank by anchor threads as long as 82 feet (25 meters).
In the 2004 movie "Spider-Man 2," the superhero slings silk from his wrists to keep a runaway subway from plunging off the end of the tracks. Far-fetched as the scene may be, a group of physics students say Spidey's webbing material, if it was truly as strong as a spider's silk, could indeed stop a train.
"It is often quoted that spiderwebs are stronger than steel, so we thought it would be interesting to see whether this held true for Spider-Man's scaled-up version," Alex Stone, a 21-year-old physics student at the United Kingdom's University of Leicester, said in a statement. "Considering the subject matter we were surprised to find out that the webbing was portrayed accurately."
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