Biologists at the University of Massachusetts Amherst have released the first broad-scale, comparative, fine-grained analysis linking the amplitude, or volume, of a bird's song to its vocal frequency, ...

The pitch of a sound is how quickly the sound wave travels. If a sound wave is travelling quickly, we say that it is a high sound. If a sound wave is travelling slowly, we say that it is a low sound.

The Doppler effect is an observed change in pitch (how high or low a sound is) when either the source of the sound or the listener is in motion. Imagine a car, its horn blaring, approaching you as you ...