chapter 43 behavior ecology. behavior is any action that can be observed and described behaviors...

Chapter 43

Behavior Ecology

• Behavior is any action that can be observed and described

• Behaviors have a genetic basis and environmental influences

• Experiments using lovebirds show that hybrids show intermediate nest building methods

• Feeding habits of two different garter snakes and their hybrids show a genetic basis

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Inland garter snake does not eat slugs.

Coastal garter snake eats slugs.

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(Coastal): © John Sullivan/Monica Rua/Ribbitt Photography; (Inland): © R. Andrew Odum/Peter Arnold, Inc.

• Maternal behavior in mice depends on gene called fosB

• When mothers first inspect their young, information sent to hypothalamus

• fosB alleles are activated and a particular protein is produced

• End result is a change in neural circuitry in hypothalamus and causes good maternal behavior

• Mice that lack good maternal behavior also lack fosB alleles so hypothalamus does not activate any enzymes and other genes for good mother behavior

• Originally thought that some behaviors were fixed action patterns that were elicited by signal stimulus

• With new experiments, many FAPs improve by learning

• Learning is defined as a durable change in behavior brought about by experience

• Imprinting is a form of learning first observed in birds when chicks, ducklings, and goslings follow the first moving object they see after hatching

• This is usually their mother

• Has survival value and leads to be able to recognize one’s species and appropriate mates

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© Nina Leen/Time Life Pictures/Getty Images

• Associative learning is a change in behavior that involves an association between two events

• Both classical conditioning and operant conditioning are examples

• In classical conditioning, two different types of stimuli (at same time) cause animal to form association between them

• Work of Russian psychologist Ivan Pavlov

• In operant conditioning, a stimulus-response connection is strengthened

• Rewards for proper response

• B. F. Skinner known for lab work on operant conditioning

• Believed giving positive reinforcement more successful than punishing undesirable behaviors

• Migration is long-distance travel from one location to another

• Requires orientation, the ability to travel in a particular direction

• Many birds use sun and stars to orient themselves

• They have biological clock within and a sense of time to compensate for sun movement

• Experienced birds can navigate

• They change direction in response to other environmental clues like Earth’s magnatic field

Fig. 43.6

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Breedingrange

Winteringrange

typical migratoryroute of starlings

experimental relocationof all starlings

flight path ofexperienced starlings

flight path ofinexperienced starlings

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• Animals may learn through imitation and insight

• An example is Japanese macaques

• Insight learning occurs when an animal suddenly solves a problem without any prior experience with the situation

• Chimps stacking boxes; ravens pulling meat attached to a string up

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Ravens learn to retrieve food

• Some animals form a society in which members organize in a cooperative manner beyond sexual and parental behavior

• Communication is an action by a sender that may influence the behavior of a receiver

• Pheromones are chemical signals in low concentration that are passed between members of the same species

• Moths, ants and termites, cheetahs and other cats

• Humans have vomeronasal organ in the nose that can detect odors and pheromones

• Auditory communication is fast, effective night or day, and can be modified

• Visual communication used by species active during day

• Tactile communication occurs when one animal touches another

• Grooming in primates, cements social bonds within a group

• Honeybees use a combination of methods especially tactile in directing others to food source

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© OSF/Animals Animals/Earth Scenes

• Behavioral ecology assumes behavior is subject to natural selection

• For food gathering, animals often have a particular home range where they spend most of the day

• One part of range defended from other members of species is their territory and behavior is territoriality

• Food gathering is technically called foraging for food

• Optimal foraging model states that it is adaptive for foraging behavior to be as energetically as possible

• Animals that take in more energy likely have more offspring

• Most primates are polygamous and males monopolize multiple famales

• Because of gestation and lactation, females invest more in offspring than males

• Males are expected to compete with other males for limited number of receptive females

• A few primates are polyanthrus where one female mates with more than one male

• Some primates are monogamous which means that they pair bond, and both male and female help with the rearing of the young

• Sexual selection is a form of natural selection that favors features that increase an animal’s chances of mating. Sexual selection often results in female choice and male competition

Fig. 43.15

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© D. Robert & Lorri Franz/Corbis

• Group living can help an animal avoid predators, rear offspring, and find food

• Disadvantages include disputes over feeding and sleeping sites

• Altruism is a behavior that has the potential to decrease the life-time reproductive success of the altruist, while benefiting reproductive success to another member of the society

• Genes passed to next generation in two different ways

• 1) Direct when parent can pass a gene directly to offspring

• 2) Indirect when a relative that reproduces can pass the gene to the next generation

• Individual selection, called kin selection, is adaptation to environment due to the reproductive success of the individual’s relatives

• Inclusive fitness of an individual includes personal reproductive success and reproductive success of relatives

• In reciprocal altruism, animals aid one another for future benefits