Animals usually move from one place to another in search of food, water and for their shelter.

Movement in animals range from simple distances i.e., few millimeters to long distances that may span hundred to thousands of kilometers. Some animals travel long distances for food and give birth to their young ones. Some of the fast moving mammals inhabit grass lands (large open lands) that is more convenient for their running. For example cheetah chases its prey at a speed of up to 70 miles an hour. Few animals such as zebras , antelopes and ostriches run fast to escape from their predators. The movement in all these animals are under substantial genetic influence and hence these movements are called as directed movements. The following are few directed movements in animals.

Kinesis: A kinesis is a movement or a simple change in activity of a cell or an organism in response to a stimulus. For example sow bug, they are other wise called wood lice is crustacean, living in a terrestrial environment. They survive best in moist environments. They exhibit kinesis in response to variations in humidity. The sow bugs are more active under dry conditions and less active under moist conditions. Even though sow bugs do not particularly move towards or away from specific conditions, their movement is increased under dry conditions to encounter a moist place to stay there.

Taxis: This concept is in contrast to kinesis which is a non–directional change in activity, in response to the stimulus. Taxis is the behavioral response of an organism in response to the directional stimulus or gradient of stimulus intensity. The movement may be towards the stimulus called as positive taxis or away from the stimulus called as negative taxis. An example of stream fish (trout), exhibit positive rheotaxis ie., they tend to swim towards the water current. This kind of taxis keeps the fish to move away, but keeps them facing the direction of food they obtain.

Migration: Animals that are difficult to survive in their live habitats in year round, evolved a way to cope with the difficult time of year. Most mammals and other species undergo hibernation. Migration is another option for animals that can move across long distances in their difficult times. They survive by leaving the area for part of the year or part of their life, and move to habitats that are more hospitable to them. The most common reason for their migration is to obtain food, shelter, and water that vary with seasons, or life stage as the availability of food and water can change throughout the year. For instance, the lack of insects and leaves in the winter results in less availability of food to eat.

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