Taxis is a directional response shown by movement of part or whole of the body, in response to an external stimulus.
If the animals move towards stimulus is called positive orientation and if away from the stimulus is called negative.
Taxis are of the following types on the basis of nature of the stimulus
Movement of an organism in response to light is called Phototaxis. e.g: Insects move towards the light is an example
of Positive phototaxis whereas cockroach moves away from the light is an example of negative phototaxis.
Chemotaxis : Movement of an organism in response to a specific chemicals is called Chemotaxis.
Ex. – Negative Chemotaxis is shown by Mosquito by moving away from antimosquito repellent.
Ant moves towards the sugar is an example of Positive chemotaxis.
Thermotaxis :- Directional response given by an animal in response to heat.
Geotaxis :- Directional response given by an animal in response to gravity.
Rheotaxis :- Directional movement of an organism in response to flowing water or air or resistance.
Ex:- Planaria moves against water current whereas butterfly fly with the current of wind.
Aerotaxis :– It is a type of chemotaxis but in this response chemical is oxygen is taken as a stimulus.
Magnetotaxis :- Response to the stimulus of magnetic field.
certain motile bacteria show response to e magnetic field.
Hygretaxis – Response to the stimulus of moistue
Thigmotaxis – Response to the stimulus of Touch,
Klinotaxis :- In this taxis animals move their head side by side to be stimulated. If it is equally stimulated they move approximately in straight line.
Tropotaxis :- In this taxis orientation of animals is influenced by both external stimulation & internal state of organ of the animals.
Telotaxis:- When orientation of animal doesn’t depend upon simultaneous comparison of two stimulations. When there are two sources of Stimulation, the animal moves towards only one direction & never in median direction.
Ex :- Hermit crab Presented with two sources of light. Each part of the track is directed towards one light only.
Menotaxis :- Light Compass responses involve orientation at a constant angle to the direction of a source of stimulation, is known as Menotaxis.
Example :- The path of homing arts is guided by the direction of the sun & compass both. Homing ants change their direction in relation to the change in position of the sun even when they are captured & kept in dark boxes. If a homing ant is held for 2.5 hours in a dark box (by the time the sun will have to travel approximately 37 degree ) & then released. It shifts its direction of movement approximately 37 degree, maintaining its original angle to the sun.
Mnemotaxis :- Orientation of animals without configurational stimuli is known as Mnemotaxis.
Example :- Hunting wasp (Philanthus triangulam) uses a number of landmarks simultaneously when returning to its nest. Removal of any of the landmark disturbs the path of hunting wasp while returning to the nest.