Goals • Define and distinguish between the proximate and ultimate causes of behavior. • Describe the adaptive advantage of innate behaviors. • Describe the respective roles of genetics and the environment in shaping behavior. • Define the six types of learning discussed in lecture. • Define search images and optimal foraging. • Explain how courtship rituals are adaptive. • Compare monogamous and polygamous • Define social behavior and sociobiology
Goals 9. Define a territory and describe the ways in which territories are used, identified, and defended. 10. Define agonistic behavior and explain how agonistic behavior is adaptive. • Explain how dominance hierarchies are maintained and identify their adaptive value.
Behavioral Ecology • the study of behavior in an evolutionary context. • Behavior: an animal’s responses to internal and external environmental cues.
Behavioral Ecology Questions • 2 types 1.Proximate questions concern the immediate reason for the behavior. • How is it triggered by stimuli (environmental cues that cause a response)? • What physiological or anatomical mechanisms play a role? • What underlying genetic factors are at work? • Proximate causes are the answers to such questions about the immediate mechanism for behavior. 2.Ultimate questions address why a particular behavior occurs. Ultimate causes are the evolutionary explanations for behavior.
Ex. Proximate & Ultimate Causation • Proximate Cause: simple reflex • Ultimate Cause: Natural Selection for behavior that minimizes damage
Innate Behavior • under strong genetic control • are performed in virtually the same way by all individuals of a species • Inflexible • “built-in” • Ex. Birds hatching from eggs • Not breathing under water
Fixed Action Patterns (FAPs) • an unchangeable series of actions • triggered by a specific stimulus. • Once initiated, the sequence is performed in its entirety, regardless of any changes in circumstances.
Figure 35.2A Egg Retrieval FAP
Genetics & Environment • Animal behavior often involves a combination of genetic programming and environmental factors • Fruit Flies • learning and memory, • internal clocks, • courtship, and • mating behaviors.
Figure 35.3 High-interaction mother Low-interaction mother Pups become relaxed adults Pups become fearful adults Female pups becomehigh-interaction mothers Female pups becomelow-interaction mothers Cross-fosteringexperiment Pups become relaxed adults Pups become fearful adults
Learning • modification of behavior as a result of specific experiences. • Learning enables animals to change their behaviors in response to changing environmental conditions. • There are various forms of learning • a simple behavioral change in response to a single stimulus • complex problem solving using entirely new behaviors
Habituation • Simple type of learning • Loss of response to a stimulus after repeated exposure • animal learns not to respond to a repeated stimulus that conveys little or no information • In terms of ultimate causation, habituation may increase fitness by allowing an animal’s nervous system to focus on stimuli that signal • food, • mates, or • real danger. • Think: the boy who cried wolf
Imprinting • Irreversible learning • limited to a specific phase in an animal’s life called a sensitive period. • Ex. • a young bird learning to identify its parents • song development in birds • “Baby Duck Syndrome” (humans & computers)
Spatial Learning • Movement can be a reaction or a product of learning • Kinesis is a random movement in response to a stimulus • Taxis is a response directed • toward (positive taxis) or • away from (negative taxis) a stimulus
Spatial Learning Cont’d • animals establish memories of landmarks in their environment that indicate the locations of • food, • nest sites, • prospective mates, and/or • potential hazards • Movement guided by learning landmarks
Associative Learning • Associate one environmental feature with another • MEMORY • Link a stimulus to an outcome • Ex. Dogs associate lease with walks • Trial & Error: associate a behavior with an outcome Forming Connections
Social Learning • learning by observing the behavior of others. • Ex. Many predators learn some of their basic hunting tactics by observing and imitating their mothers.
Problem Solving Learning • Ability to apply past experiences to new situations • Cognition: the ability of an animal’s nervous system to perceive, store, integrate, and use information gathered by the senses. • Problem-solving behavior • is highly developed in some mammals, especially dolphins and primates, and • has been observed in some bird species.
Foraging Studies • Behavioral Ecologist study how animal forage • Generalists, specialists, etc. • Search Image: mechanisms animals use to find specific food sources
Cost v. Benefit • Trade-offs involved in food selection • The amount of energy may vary considerably in • locating • capturing • preparing prey for consumption • Optimal foraging theory predicts that an animal’s feeding behavior should provide • maximal energy gain with minimal energy expense an • minimal risk of being eaten while foraging.
Communication • Behavioral ecologist study communication between organisms • Interactions dependent upon communication • Animal communication includes • Sending signals • Receiving signals • responding to signals • Forms of communication vary considerably • Ex. Nocturnal (odor & sound) • Ex. Honeybee dances • Communication essential for mating
Mating • Courting Rituals: elaborate communication • Confirms that: • individuals are of the same species, • of the opposite sex, • physically primed for mating • not threats to each other.
Mating Systems • Connected to reproductive & child rearing success 1. Promiscuous systems • No strong pair-bonds • Fleeting relationships between males and females. 2. Monogamous systems • one male and one female • both parents participating in parental care • Rare 3.Polygamous systems • have one individual of one sex mating with several of the other • usually consist of one male and many females.
Offspring Viability & Mating System • Needs of offspring & certainty of paternity shape mating system & paternal care by males • Cost v. Benefit relationship • Ex. Birds and Monogamy • Ex. Pheasants & Polygamy
Cost v. Benefits Costs of Parental Care Benefits Females Almost certain success (pass on genes) Males Paternity is never certain Mating & birth separated by time in many cases Harems up odds • Energy • Loss of mating opportunities
Sociobiology (Social Behavior) • Applies evolutionary theory to the study and interpretation of social behavior to explain how social behaviors • are adaptive and • could have evolved by natural selection • Social behavior: any kind of interaction between two or more animals
Territorial Behavior • Territory is an area, usually fixed in location, • which individuals defend • other members of the same species are usually excluded. • Territories are usually used for • feeding, • mating, • rearing young • How are territorial behaviors beneficial?
Agonistic Behavior • Conflicts over resources settled by agonistic behaviors • threats, rituals, and sometimes combat that determines which competitor gains access to a resource • can directly affect an individual’s evolutionary fitness • Ritualization favored
Dominance Hierarchies • Ranking of individuals based on social interactions. • Ex • pecking order in chickens • females within a wolf pack • Established & Maintained with agonistic behaviors
Human Behavior • Genes & Environment • Twin studies suggest 50% of complex behavior has a genetic factor • Genes do not dictate behavior but, instead, cause tendencies to react to the environment in a certain way. • The mechanisms and underlying genetics of behavior are proximate causes. • Sociobiologists explore the ultimate causes of human behavior.