Kinesis and taxis are behavioral mechanisms relating to stimulus and movement in animals, including pillbugs. An example of taxis is the pillbug searching for food, while an example of kinesis is the pillbug's level of activity in a humid area.
According to Encyclopædia Britannica, taxis is a directional response by an organism to a stimulus. This response can be either positive or negative, depending on how the organism perceives the stimulus. Kinesis, comparatively, is also a response to stimuli, but it is not confined to direction. In kinesis, the stimulus might affect the organism's speed. Both kinesis and taxis are related to reflexes in biology.