Chapter 44 Animal Behavior

Chapter 44Animal Behavior

Section 1

Development of Behavior

The Study of Behavior• Snakes play dead

• Chimpanzee gathers termites on stick

• Leaf-cutter ants cut leaves and take bits back to their nest- colony helps load food

• Ethologists- biologists who study behavior

The Study of Behavior• Behavior- action or series of

actions performed by an organism, usually in a response to a stimulus

• To learn more, ethologists ask questions

• 1. What causes the behavior? What are the mechanisms that respond to a stimuli?

• 2. What is the role of genes in the behavior, and how does it develop during an individual’s lifetime?

• 3. What is the behavior’s evolutionary history?

• 4. How does the behavior affect the organism’s survival and reproduction?

Genes and Behavior• Ethologists ask how much

behavior is based on genetics and how much is based on the environment

• Example: aggressive animals- snapping turtle vs tiger or bear

Natural Selection & Behavior• Animals promote offspring

production by changing their surroundings

• Example: new male lion takes over a pride- he kills all young cubs so that he is only the father of all new offspring

Innate Behavior• Innate behavior- instincts-

inherited actions that are performed effectively the first time without being taught

• Example: spider webs & hatchling sea turtles

Fixed Action Pattern• Fixed action pattern- rigid innate

behavior that all members of a species perform the same way each time

• Example: eastern hognose snake- spreads its jaws, hisses, and rolls on its back when threatened (plays dead)

Learned Behavior• Actions change with experience

• Learning- modification of a behavior based on experience

• Simple or complex

• What are some examples of learned behavior that you display?

Habituation• Habituation- animal learns to

ignore a frequent, harmless stimulus

• Example: Sea gulls- shadows from overhead cause them to hide, overtime they learn that small objects (leaf) is not dangerous, but a larger object (hawk) is

Operant Conditioning• Operant conditioning- trial and

error learning

• Example: dog learns a cat hissing and arched back is dangerous when it gets scratched

• Example: B.F. Skinner- rat in box trained to pull level if food came out

Classical Conditioning• Classical conditioning- animals

learn to associate a response with a previous stimulus

• Example: ringing a bell and a dog salivating

Problem-Solving & Reasoning

• Reasoning- type of problem solving- involves the ability to solve a problem not previously encountered by the individual in a way that is not dictated by instinct

• Example: chimp using tool to get insects

• Other examples?

Genes, Learning, & Behavior

• Genes can shape behavior

• Behaviors are also shaped by an animal’s experience

• But, overall, behavior is shaped by both genes and by experience

Imprinting• Imprinting- form of learning in which

young animal forms permanent associations with its environment

• Example: geese learn to follow the first thing they see when they hatch (humans)

• Example: sea turtles hatch and return to same beach to lay eggs years later

Imprinting• Sensitive period- imprinting

occurs during a specific phase in an animal’s development

• Example: young children can learn multiple languages

REVIEW!!!• What are four questions that an

ethologist might ask when studying behavior?

• How is it possible for natural selection to affect an innate behavior?

• Describe four types of learned behavior.