Behavior

Behavior is the way that living things respond to their environment. A behavior consists of a response to a stimulus or factor in an individual's internal or external environment. Stimuli include chemicals, heat, light, pressure, and gravity. All living things exhibit behavior. When dust irritates our throats, for example, we respond with coughing behavior. Plants respond with growth behavior when light stimulates their leaves. Generally, behavior helps organisms survive. Behavior can be categorized as either innate or learned, but the distinction is frequently unclear. Learned behavior often has innate or inborn components. Behavior is considered innate when it is present and complete without the need for experience. Babies, even blind ones, at about four weeks of age smile spontaneously at a pleasing stimulus. Such innate behavior is stereotyped (always the same) and, as a result, quite predictable. Plants, protists, and animals that lack a well developed nervous system rely on innate behavior. Higher animals use both innate and learned behavior.