Animal Behavior is the scientific study of the wild and wonderful ways in which animals interact with each other, with other living beings, and with the environment. It explores how animals relate to their physical environment as well as to other organisms, and includes topics such as how animals find and defend resources, avoid predators, choose mates, reproduce, and care for their young.
Previous lesser definitions of Animal Behavior include:
- "Behavior is motion". "Movement, not necessarily movement of the whole animal... muscular contractions" or "The whole function of the nervous system can be summed up in one word, conduction."  - In Sherington's view the basic element of behavior was formed in a reflex-arc, where receptor organs receive sensory stimuli and are conducted to an effector organ. This highly reductionist position has received criticism from many angles, specifically, from arguments that it fails to account for spontaneous behaviors, behaviours that are characterized by a lack of motion, as well as disregarding the complexity of emergent properties in behavior.
- "What a plant or animal does, in the course of an individual's lifetime, in response to some event or change in its environment."  - This definition reduces behavior to phenotypic plasticity, and is thus not specific enough.
- "Behavior is all observable or otherwise measurable muscular and secretory responses (or lack thereof) and related phenomena in response to changes in an animal's internal or external environment.”  Behavior may include components which do not lend themselves to simple quantification.
- "Behavior is characterized by entropic and energetic transductions by an organism, in which the long-term averages convert high entropic and low energetic sensory inputs into low entropic and high energetic outputs."  - This definition is too incomprehensible to be of great use.
- Sherrington CS. 1899. On the Spinal Animal (The Marshall Hall Lecture). Medico-Chirurgical Transactions, London 82: 449-477
- Silvertown J & D Gordon, 1989. A framework for plant behaviour. Annual Review of Ecology & Systematics, 20, 349-366
- Grier JW & T Burk, 1992. Biology of Animal Behaviour. Mosby Year Book, St. Louis
- Hailman JP. 1977. Optical Signals: Animal Communication and Light. Indiana Univ Press, Bloomington