What do frog calls and human eyes have in common? They have both inspired the improvement of modern-day technologies, from wireless networks to ink jet printers. Here’s how:
VI. De-synching mating calls: Like many species, male Japanese tree frogs (Hyla japonica) try to attract the attention of females by projecting some apparently sexy-sounding call. In order to ensure that their calls dont get delivered simultaneously (which would be very confusing for the poor girls), they have learned to employ a self-organizing system whereby calls from each male are desynchronized. Researchers have used this same technique to code network nodes in a way that maximizes information transmission and energy efficiency.
Hernández & Blum. 2012. Distributed graph coloring: an approach based on the calling behavior of Japanese tree frogs. Swarm Intelligence 6: 117 doi: 10.1007/s11721-012-0067-2
VII. Staying open but not dry: Like the human eye, ink jet nozzles need to stay open but cannot dry out. To prevent moisture from evaporating from our eyes, we have a film of oil covering them. Researchers at the University of Missouri have mimicked this in office supplies by using a droplet of silicone oil to cover the opening of ink jet nozzles when they are not in use. Interestingly, further extension of the human eye mechanism was limited by physics: while our eyelids work to spread the oil over the surface of the eye, similar eyelid-like shutters on the small surface of nozzles would actually get stuck due to high surface tension. Instead, electic fields are used to move the oil droplet.