'Spiders harness the power of music'

Spider silk, when plucked like a guitar string, transmits vibrations across a wide range of frequencies so that its sound carries information about prey, mates, and the structural integrity of a web, scientists say.
The researchers fired bullets and lasers at spider silk to study how it vibrates.
They found that, uniquely, when compared to other materials, spider silk can be tuned to a wide range of harmonics.
The findings not only reveal more about spiders but could also inspire a wide range of new technologies, such as tiny light-weight sensors, researchers said.
"Most spiders have poor eyesight and rely almost exclusively on the vibration of the silk in their web for sensory information," said Beth Mortimer of the Oxford Silk Group at Oxford University, who led the research.

"The sound of silk can tell them what type of meal is entangled in their net and about the intentions and quality of a prospective mate. By plucking the silk like a guitar string and listening to the 'echoes' the spider can also assess the condition of its web," said Mortime.

This quality is used by the spider in its web by 'tuning' the silk: controlling and adjusting both the inherent properties of the silk, and the tensions and inter-connectivities of the silk threads that make up the web.
To study the sonic properties of the spider's gossamer threads the researchers used ultra-high-speed cameras to film the threads as they responded to the impact of bullets. In addition, lasers were used to make detailed measurements of even the smallest vibration.

"The fact that spiders can receive these nanometre vibrations with organs on each of their legs, called slit sensillae, really exemplifies the impact of our research about silk properties found in our study," said Dr Shira Gordon of the University of Strathclyde.
"These findings further demonstrate the outstanding properties of many spider silks that are able to combine exceptional toughness with the ability to transfer delicate information,' said Professor Fritz Vollrath of the Oxford Silk Group at Oxford University, an author of the paper.
"These are traits that would be very useful in light-weight engineering and might lead to novel, built-in 'intelligent' sensors and actuators," said Vollrath.

The research was published in the journal Advanced Materials.