Chapter 29 Animal Behavior

Section 1 Elements of Behavior

Behavior and Evolution BEHAVIOR is the way an organism reacts to stimuli in its environment. Behaviors essential to SURVIVAL and reproduction include finding and catching FOOD, selecting a HABITAT, avoiding PREDATORS, and finding a MATE.

Behavior and Evolution Some behaviors can be influenced by GENES and can be INHERITED. Certain behaviors evolve under the influence of NATURAL SELECTION:

Behavior and Evolution If a behavior increases an individual’s FITNESS and is influenced by GENES, it tends to spread through a population. Over many generations, ADAPTIVE behaviors can prove important in the survival of populations and species.

Innate Behavior An INNATE BEHAVIOR, also called an instinct, is fully functional the first time it is performed, although the animal has no previous experience with the STIMULUS. All innate behaviors depend on patterns of NERVOUS SYSTEM activity that develop through complex interactions between GENES and the ENVIRONMENT.

Learned Behavior Acquiring changes in behavior during one’s lifetime is called LEARNING. There are four types: HABITUATION is the process by which an animal decreases or stops its response to a REPETITIVE STIMULUS that neither rewards nor harms the animal.

Learned Behavior In CLASSICAL CONDITIONING, a certain stimulus comes to produce a particular RESPONSE, usually through an association with a POSITIVE or NEGATIVE experience. OPERANT CONDITIONING (a form of trial-and-error learning) is the use of a REWARD or PUNISHMENT to teach an animal to behave a certain way through REPEATED practice.

Learned Behavior INSIGHT LEARNING occurs when an animal applies to a new situation something that it learned previously in another context.

Complex Behaviors Many complex behaviors combine INNATE behavior with LEARNING. Imprinting is a complex behavior. IMPRINTING is the process by which some animals, such as BIRDS, recognized and follow the first moving object they see during a critical period in their early lives.

Animals in Their Environments Section 2 Animals in Their Environments

Behavioral Cycles Many animals demonstrate daily or seasonal cycles in their behavior. CIRCADIAN RHYTHMS are behavioral cycles that occur daily. MIGRATION is the seasonal movement from one environment to another.

Behavioral Cycles MIGRATION is the seasonal movement from one environment to another. For example, many birds find food and nesting sites in the north in the SUMMER, but they fly south to warmer climates for the WINTER.

Social Behavior Interactions among animals of the same species are social behaviors. There are several types: Animals (usually the MALES) perform COURTSHIP behaviors to attract a mate. An elaborate series of courtship behaviors is a COURTSHIP RITUAL.

Social Behavior Many animals occupy a specific area, or TERRITORY, that they defend against COMPETITORS. Animals may use threatening behaviors, or AGGRESSION, to defend their territories. Animals may also use aggression when they compete for RESOURCES.

Social Behavior Some animals form a SOCIETY, or a group that interacts closely and often COOPERATIVELY. The theory that helping a relative survive increases the chance of transmitting one’s own genes is KIN SELECTION.

Social Behavior The most complex animal societies are those formed by social INSECTS such as ANTS, BEES, and WASPS. All animals in the society cooperate closely to perform complex tasks, such as NEST CONSTRUCTION.

Communication The passing of information from one individual to another is COMMUNICATION. Animals use a variety of signals for communication, including VISUAL, CHEMICAL, and SOUND. LANGUAGE is a system of communication that combines SOUNDS, SYMBOLS, and GESTURES according to rules about sequence and meaning.