We achieved our goals by staging ten-minute separations during which the animals' vocalizations were recorded as well as their behavior. This way we could go back, listen to our tapes, and record how long each animal spent doing a certain behavior. After taking all of the measurements, we were able to compare the behavior of the siblings with that of the non-siblings. In order to analyze the vocalizations, we entered the calls into the computer and used a program called SoundEdit on the Macintosh. The vocalizations could then be viewed on the screen in the form of a sonograph, which plots a frequency versus time picture of the call.
People are surprised the first time they hear a cheetah call.
Most of the calls sound like very loud bird chirps, but sometimes they meow, much like a house cat. It is thought that the purpose of the vocalizations is two-fold. First of all, they indicate to others that the animal is stressed. Second, they are used by the animal to locate his missing coalition partner. The difference in vocalization rate between periods of separation and normal conditions was tremendous.