Airdate: Nov 05, 2015
Scientist: Rolf Mueller
Bats - Unanswered Questions
The bat's brand of sonar is much more sophisticated than ours.
That's the sound of bats echolocating. Bats use these pulses to navigate and catch their prey. It's their own brand of sonar and its much more sophisticated than ours. I'm Jim Metzner and this is the Pulse of the Planet.
Mueller: Bats are amazingly versatile in how they use their sonar systems.
Rolf Mueller is an Associate Professor of Mechanical Engineering at Virginia Tech.
Mueller: There's bats that capture insects in the air. There's bats that capture crawling arthropods. There's carnivorous bats that hunt for mice. And in most of these pursuits, sonar plays a role. So, I think what we can learn from bats is, how can we take this very simple principle of sonar and adjust it and adopt it to do all these different things?
Mueller: The basic principle of sonar is, indeed very simple. You have source for sounds signals emit a sound signal. It travels through the environment. It is reflected by objects in the environment. These reflections come back to you as echoes. You listen to the echoes, and the interesting thing is then that the bats know what to do after they have listened to the echoes, and we don't. That's the difference. That's the performance gap.
Mueller: Now you really have the bats in a very dense situation where you wonder, how do they actually deal with the fact that there's so many of them and they are all emitting the sonar? It's supposed to work in a way that you emit a pulse, and then you listen to the echo to that pulse. But what if everybody else around you does that? How do you actually know what is coming into your ear? What part of that is echoes to your own pulse? What is other pulses? What is echoes to those other pulses? So, that's also a big, unresolved problem.
In future programs we'll hear some clues as to how bats acquire their unique sonar abilities. I'm Jim Metzner and this is the Pulse of the Planet.