Spider silk is one of the most mysterious materials on Earth, five times stronger than piano wire and as strong as steel.
Now US researchers say they have discovered why the fiber is so strong.
Using lasers, researchers at the University of Arizona were able to shed light on the the complex mechanical properties of the silk.
The laser light scattering technique fires a low-power laser into the silk strands and maps them without disturbing them, reported Science World Report.
The laser allowed the researchers to determine the variations and junctions found within the fibers, making it dense and strong.
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UPI reported that spider silk is a biological polymer with an incredibly complex structure similar to bone and collagen.
"Spider silk has a unique combination of mechanical strength and elasticity that make it one of the toughest materials we know," lead researcher Jeffery Yarger said, according to Azom.com.
The study also confirmed that spiders are able to tailor their silk as they weave.
Researchers believe that a better understanding how the silk is formed may lead to breakthroughs in new materials for human use.
"This information should help provide a blueprint for structural engineering of an abundant array of bio-inspired materials, such as precise materials engineering of synthetic fibers to create stronger, stretchier, and more elastic materials," Yarger said, reported UPI.
The findings were published in the journal Nature Materials.