kinesis

Kinesis is a type of animal behavior where an organism's movement rate or direction changes in response to a stimulus, but the organism does not orient itself in relation to that stimulus. This means the animal's body isn't pointed towards or away from the stimulus. Instead, the stimulus influences how fast or in what direction it moves.1

For example, woodlice increase their movement speed as humidity decreases, helping them find moister areas. Planarians increase their turning rate in brighter light, guiding them back to darker spots. Kineses can involve changes in speed (orthokinesis) or turning frequency (klinokinesis), or both. This is distinct from taxis, where an animal actively orients itself towards or away from a stimulus.12