In “Super Sensitive Spider Sensilla” (The Scientist , October 28, 2011), Jef Akst reports “Researchers measure the responsiveness of a spider’s slit sensilla, sensory organs embedded in the exoskeleton that sense vibrations”:
The sensilla are comprised of minute parallel slits. Nearby vibrations result in physical forces that compress and stimulate the sensors. Clemens F. Schaber of the University of Vienna and his colleagues used powerful optical and micro-force measurements and found that the sensory organs responded to forces as small as 0.01 milliNewtons—less than half a percent of the body weight of a typical cockroach.
Scare the kids with this.
Here’s the part some of us don’t get: Was there ever a time spiders couldn’t do this? Or walk upside down on the ceiling?