recap

52.1 recap

Early scientific studies of animal behavior took two approaches. Behaviorists focused on the study of conditioned behavior in a few species of laboratory animals and asked questions about learning. Ethologists studied genetically determined behavior in many species in their natural environments and asked evolutionary questions.

learning outcomes

You should be able to:

  • Differentiate between behaviorism and ethology.

  • Explain the significance of deprivation experiments.

  • Explain what proximate and ultimate causes of behavior are, using examples.

Question 1

What distinguishes fixed action patterns from behaviors resulting from Pavlovian or operant conditioning?

Fixed action patterns are genetically determined, adaptive behaviors that are usually activated by specific stimuli normally encountered in nature. Pavlovian conditioned reflexes are physiological processes triggered by learned, non-natural stimuli. Behaviors resulting from operant conditioning are random behaviors without physiological or adaptive significance; they are activated by non-natural stimuli that the animal has learned to associate with receiving a reward when expressing the behavior.

Question 2

What variables might account for a genetically determined behavior not being expressed in a deprivation experiment?

A genetically determined behavior might not be expressed in a deprivation experiment if the animal is not in the appropriate developmental stage or physiological condition, and if the necessary stimuli for the behavior are absent.

Question 3

What are proximate and ultimate causes of mating-display behavior?

Proximate causes of mating-display behavior include physiological reproductive condition and presence of stimuli from a sexually receptive conspecific. The ultimate cause of mating-display behavior is reproductive success—how many of one’s offspring live and mature to contribute to the next generation.

The work of the ethologists left no doubt that behavior can be genetically determined, but how? Genes code for proteins, whereas behaviors are highly complex traits involving sensory input and intricate patterns of control over responses to that input. Is it reasonable to think that a single gene can have a specific effect on a behavior?