Animal behavior

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 weather
• D. 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 behavior

• Courtship behavior: actions males and females carry out before mating
• Insures that members of the same species find each other and mate
• May protect male from being eaten long enough to mate

3. Territoriality

• Physical space an animal defends against own species
• May include breeding, feeding, or mating areas or all three
• Reduces competition so improves survival
• Pheromones may mark boundaries

4. Communication: ants and bees using pheromones

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

5. Aggressive Behavior

• Intimidates others of same species
• Used to defend young, territory, food
• Teeth baring, growling, bird calls
• Rarely 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?