Here is a riddle for you. Name two things that a high tech fisherman, a killer whale and a bat, have in common. Hmm.
I’m Lisa Strong for the Petersburg Marine Mammal Center.
While these creatures inhabit very different environments – land, sea and sky — the first thing a fisherman, a killer whale, and a bat have in common is, they’re all mammals. Okay, that was easy.
The second thing they have in common is they use sound to find food. A high tech fisherman uses technology to look for the fish he’s after. Think of a fish-finder or a depth sounder. These devices use sonar to “see” with sound. They emit a sound that travels through the water. When it hits an object, the sound’s reflected back towards the device, which catches the echo and pinpoints the object underwater. Killer whales and bats don’t need an external sonar device, because theirs is built in.
Their built-in biosonar is called echolocation. We can hear the echolocation clicks of a killer whale with an underwater microphone. The fish-eating resident killer whales use echolocation to find schools of salmon to eat. They generate clicks that go out and bump into objects, hopefully a fish or even better, a school. The sound bounces back, hits the killer whale’s lower jaw then transmits the echo to the ears. The brain then builds an acoustic image of what’s in front of a whale.
The echolocation sound a bat makes is so high in frequency, we can’t hear it. But researchers have recorded the sounds and slowed them down so we can. Here’s an echolocation sound of a brown bat slowed down 10 times. Given bats nail mosquitoes in the dark all the time, you can imagine their acoustic image must be very clear and precise.
The extra credit answer is, the high tech fisherman, the killer whale and the bat, will very likely NOT get caught in your hair.
