ANIMAL BEHAVIOR

What is Behavior?

Anything an animal does in response to a stimulus

Stimulus: environmental change that directly influences an organism

Example: change in day length, heat

Innate behavior: Inherited

Natural selection favors certain behaviors

Behavior that helps survival is passed on to offspring

Examples: fixed action responses: unchangeable behavior that once begun, won’t stop till it is finished (toad sees prey, flips out tongue)

Reflexes: Automatic Responses

Simplest form of behavior

Simple automatic response to a stimulus that involves no conscious control

Example: jerking hand from hot stove

Fight or flight response

Instinctive Behavior

Complex pattern of innate behavior

Longer than a reflex

Example: greylag goose rolling eggs

Internal and external cues

A. Circadian rhythm: 24-hour wake-sleep cycle regulated by light (some nocturnal)B. Migration: instinctive seasonal movement by animals (birds, whales)C. Hibernation: inactivity during cold weatherD. Estivation: state of reduced metabolism during periods of extreme heat

E. Suckling: mammal babies instinctively know how to get nourishment from their mother

F. Taxis:

responsive movement of a free-moving organism or cell toward or away from an external stimulus, such as light.

Positive phototaxis: movement toward light

Negative phototaxis: movement away from light

Social Behavior:1. Dominance Hierarchy

“Pecking order”

Social ranking within a group

Usually a dominant male (“alpha male”) may sire most of young

2. Courtship behaviorCourtship behavior: actions males and females carry out before mating

Insures that members of the same species find each other and mateMay protect male from being eaten long enough to mate

3. TerritorialityPhysical space an animal defends against own speciesMay include breeding, feeding, or mating areas or all threeReduces competition so improves survivalPheromones may mark boundaries

4. Communication: ants and beesusing pheromones

Bees “dance” to show hive members the way to food

Ants

5. Aggressive Behavior

Intimidates others of same speciesUsed to defend young, territory, foodTeeth baring, growling, bird callsRarely leads to death, just submission

Learned Behavior: behavior changes through practice or experience

Habituation: repeated stimulus not associated with a reward or punishment, so animal eventually ceases to respond

Learned behavior: Imprinting

At a critical time in its life, animal develops a social attachment to another object

Usually irreversible

Mostly in birds

Learned behavior: Trial and Error

Animal receives a reward for a certain response

Motivation speeds up this type of learning

Usually, satisfies a need such as hunger

Learned behavior: Classical conditioning (Pavlov’s dog)

“Learning by association”

One stimulus associated with another to receive reward

Eventually, first stimulus no longer needed

Learned behavior: Insight

Most complex type of learning

Animal uses previous experience to respond to a new situation

Much of human learning occurs by insight

Which is it?