1. Chapter 51
~Animal Behavior

2. Behavior-what an animal does and why it does it.
Ethology~ study of animal behavior
Behavior results from both genes and environmental factors.
Causation:
•proximate~ physiological & genetic mechanisms of behavior
•ultimate~ evolutionary significance of behavior

3. Observation of Magnolia Warbler
Proximate
Breeds in spring and early summer
Hypothesis-effect of increased day length on photoreceptors brings on breeding.
Stimulus results in neural and hormonal changes that induce this behavior.
Ultimate
Why did natural selection favor this behavior?
Hypothesis-breeding is most productive or adaptive at this time.
Food more plentiful.

4. Innate Behavior Developmentally fixed
Often attributed to genetic programming without environmental influence.
Baby birds opening mouth for food
Key point-is the range of environmental differences among individuals does not appear to alter the behavior.

5. Innate Behavior
Fixed action pattern (FAP)~ sequence of acts; unchangeable; carried to completion
Sign stimulus ~these patterns are triggered by an external sensory stimulus
Ex: 3-spined stickleback (Tinbergen ‘73 Nobel)
Utilizes its color vision to identify red-undersided males that try to invade its territory.

6. Foraging
Mechanisms animals use to recognize, search for, and capture food items.
Optimal foraging theory
Feeding costs verses feeding benefits.

7. Behavioral ecology concentrates on ultimate hypotheses
Animals utilize their genetic variation to express behaviors that optimize their fitness
Natural selection favors behaviors that enhance survival and reproductive success.

8. Learning-experience based modification of behavior
Maturation~ behavior due to developing physiological changes.
Habituation~ loss of responsiveness to stimuli that convey no information; simple learning
Imprinting~ limited learning within a specific time period •critical period (Lorenz, ‘73 Nobel)

9. Associative Learning Connecting two different stimuli
Ivan Pavlov-Classical conditioning
Involves associating arbitrary stimuli with either a reward or punishment.
Skinner-Operant Conditioning-trial and error
Induced manipulation of levers by rats after awarding them with food.

10. Associative Learning
•classical conditioning~ Pavlov’s dogs •operant conditioning (trial and error)~ “Skinner’s box”

11. Social behavior
Sociobiology~ evolutionary theory applied to social behavior (Hamilton)
Agonistic behavior~ contest behavior determining access to resources
Dominance hierarchy~ linear “pecking order”
Territoriality~ an area an individual defends excluding others
Mating systems: •promiscuous~ no strong pair bonds •monogamous~ one male/one female
•polygamous~ one with many •polygyny~ one male/many females •polyandry~ one female/many males

12. Agnostic Behavior Competition for a resource Sometimes simply ritual
Signifies intent but causes no harm
Causes social hierarchies to develop in some animals
Dominance hierarchy
Territoriality

13. Mating behavior
Parental investment-time and resources required to produce an offspring.
Female usually has higher parental investment-eggs more costly to produce
Sexual selection-competition among males for the female to choice him.
Females usually care for young. Paternity not always know. Very few have only male paternal care.

14. Altruistic behavior-reducing individual fitness to increase that of another
Inclusive fitness~ total effect an individual has on proliferating its genes by its own offspring and aid to close relatives
Coefficient of relatedness~ measures inclusive fitness by proportion of genes that are identical because of common ancestors
Kin selection~ aiding related individuals altruistically can result in more identical genes
Reciprocal altruism~ exchange of aid; humans?