Ethology: The comparative study of behavior

1. Ethology: The comparative study of behavior

2. Antecedents of Ethology • From the turn of the century to well into the 50’s, psychology could be roughly divided into two camps. • The purposive psychologists: All behavior is goal directed, that is, it has a purpose • William Mac Dougall and later, Edward Chase Tolman believed that “instinct” could be used to explain behavior. • Instinct was believed to be infallible, and inexplicable. • This, of course, is silly

3. Antecedents of Ethology • The behaviorists argued that the controlled experiment, and the search for causal explanations of behavior was the only legitimate source of knowledge. • Problem: • A behavior must be examined experimentally in a controlled laboratory setting • Takes organism from the environment in which it normally behaves • Typically only learning processes could be examined this way • Thus, the conclusion could be reached that all behavior is learned. This is silly too.

4. Meanwhile…. • C.O. Whitman and Oskar Heinroth noticed the existence of patterns of movement with similarities and differences between species that correlated with comparable physical characters. • The same evolutionary thinking that is applied to physical traits can be applied to behavior patterns. • e.g. Homologous structures • Behavior patterns are innate, that is they are coded in the genome.

5. The birth of Ethology • Ethology: the study of the evolution, development and function of behavior. • Emphasizes the observation of organisms in their natural setting, before attempting laboratory experiments. • Ethogram: comprehensive, descriptive reports of an organisms behavior while interacting in it’s normal environment.

6. Konrad Lorenz(1903-1989) “There are mechanism of behavior which evolve in phylogeny exactly as organs do, so that concepts of homology can be applied to them as well as to morphological structures”

7. Background • Born in Altenberg, Austria. • By the age of 4, Lorenz was raising newts and ducklings. This fascination with animals was a large influence on the course of his life. • At 19, Lorenz begins a 10 year career as a motorcycle racer, while still developing his academic career. • In 1928, K.L. accepted a professorship at the University of Vienna. • During the war, K.L. became a full professor at the University of Konigsberg.

8. Background • 1941, K.L. is drafted into the German army. • 1944, K.L. is captured in Russia. Kept as a P.O.W. until 1948. Presumed dead. Writes two ethological articles on scrap paper and hand raises a starling. • K.L. restarts his career. • 1973, together with Niko Tinbergen and Karl Von Frisch, K.L. receives the Nobel Prize for developing a unified theory of motivation and behavior.

9. Example: The gray goose • The Behavior: When a gray goose sees an egg that has rolled out of its nest it retrieves the egg in a very stereotyped manner.

10. Egg retrieval in the Graylag Goose

11. The egg rolling movement: • Goose must see an egg shaped object “key stimulus”. • The tendency to perform the movement can be “exhausted” • The longer one waits after exhaustion the easier it is to reelicit the act. • The form of the movement is always the same regardless of egg size or shape.

12. The Gray Goose • The goose will continue to perform the movement even if the egg is removed during the act. • After long periods of inactivity the goose will perform the act in the absence of a missing egg. “Leerlaufreakyion-Vacuum activity”.

13. Key Stimuli • Environmental events or conditions that the animals perceptual mechanisms are tuned to.

14. Action Specific Energy (ASE) • Energy is stored specific to a given act i.e. motivational systems run on different energy. • This energy continues to build up. • If not released Vacuum Activities take place. • Example: house cat

15. Fixed Action Pattern (FAP) • The genetically programmed core of a species typical behavior. • A highly stereotyped innate movement pattern that is based on activity in a specific coordinating center in the CNS. • FAP is released by appropriate key stimuli and runs to completion regardless of further stimulation (endogenously driven). • Squirrels and Nuts

16. Types of Behaviors • Appetitive Behavior: Those behaviors that place the animal in contact with relevant key stimuli. Goal Oriented. • Consumatory Behavior: The final phase of a motivated behavior that occurs following perception of key stimuli.

17. Innate Releasing Mechanism (IRM) • The FAP central coordinating center is normally held under inhibition by the IRM. • When the appropriate stimuli are presented (key stimuli) the IRM releases it’s hold on the FAP and the stored ASE is used to produce the appropriate chain of behaviors. • The IRM can be thought of as a lock and the Key stimulus as a Key.

18. Lorenz’s Psychohydraulic Model

19. Supra-normal Sign Stimuli • A supra-normal sign stimulus is one that mimics and “outdoes” normal sign stimuli.

20. The Ethological Contribution • The concept that our sensory apparatus are tuned to respond to certain stimuli and not others. • The concept that how we, and other organisms, learn may be dependent upon innate programs. • That what can be learned is biologically constrained. • That human behavior can be understood though an evolutionary perspective.

21. Human Ethology • Humans have F.A.P.’s as well • The eyebrow flash • Eye rubbing • Shoulder shrug to ward off attack • Covering head with hands • Smiling • Visual illusions • F.A.P.’s in humans not as rigid as those in other organisms. • Study the sign stimuli that release human F.A.P.’s

22. The “eyebrow flash” is seen in all cultures. Innate Behaviors in Humans

23. Innate behaviors in humans

24. Sign Stimuli in Human Behavior • The corpus adipose buccae in infants. • Consider sexual dimorphisms as possible key stimuli: • Secondary sex characteristics: • Differential deposition of fat. • Deep voice vs. High voice • Beard

25. Sign Stimuli in Human Behavior • When threatened there is a tendency to rotate the arms inward and raise the shoulders. Males may “puff up” the chest. • When frightened small muscles on the arms, back, and shoulders tense causing the hair to stand erect (pyloerrection).

26. Direction of hair growth in modern man:

27. Loss of body hair results in males accentuating the shoulders artificially:

28. Sign Stimuli in Human Behavior • Response to Supra-normal stimuli utilized by fashion and cosmetics industry. • Mascara accentuates the eyes • Rouge accentuates “rosy cheeks” • Lip Stick accentuates “full Lips”

29. Supra-normal stimuli in Humans