'wiggle' is a useful expression particularly for character animation. again, the red highlighted code represents the key frames which are being expressed, with each value 'relative to the frequency and duration of movement around a specific area of interest'. this is good for providing subtle movements, a strong feature of smooth, organic animation.
the screen shot illustrates this for albern's face. i combined the expression with the puppet tool to animate specific areas, and 'wiggle' them accordingly. it is more obvious on the eyebrows, less so around the mouth.
