SO: v4 (First Timers)

ELEPHANTS INFRA-SOUNDS:  A huge pipe organ can play notes that move lower and lower until you can no longer hear them.  They will eventually be so low that you will be able to feel the vibration of the notes that are too low to hear.

ELEPHANTS INFRA-SOUNDS:  Katy Payne worked with elephants in the Portland Zoo in Oregon. She sometimes felt a strange vibration when she was near elephants even though she couldn’t hear anything.

ELEPHANTS INFRA-SOUNDS:  A person’s vocal cords are surprisingly thin. They are about two inches thick.

ELEPHANTS INFRA-SOUNDS:  An elephant’s vocal cords are about 3 inches long. Elephants can make deep infrasound with them.

ELEPHANTS INFRA-SOUNDS:  Elephants use infrasound to communicate over long distances of hundreds of miles.

ELEPHANTS INFRA-SOUNDS:  Elephants can “hear” the ground vibrating from infrasound through their feet.

SONAR FUN:  Sonar operators in WW2 submarines often picked up strange readings with their sonar. The subs detected what seemed to be a rising and falling ocean floor.

SONAR FUN: Lanternfish have a special body part called the swim sack.

SONAR FUN: In the story in the core video, submarine sonar reflected off the pressurized swim bladders of millions of the tiny lanternfish deep below the submarine.

SONAR FUN:   The rising and falling of millions of the fish was due to the feeding patterns of the colonies.