Chapter 55: Behavioral Ecology (Part 1, Week 3) Flashcards
[Start Chapter 55 Behavioral Ecology]
What is the observable response of an organism to an external or internal stimulus?
Behavior
What is a subdiscipline of organismal ecology that focuses on how the behavior of an individual organism contributes to its survival and reproductive success, which, in turn, eventually affects the population density of the species?
Behavioral ecology
What do you call scientific studies of animals?
Ethology
What is a specific genetic and physiological mechanism of behavior?
Proximate cause
For example, we could hypothesize that male deer rut or fight with other males in the fall because a change in day length stimulates the eyes, brain, and pituitary gland and triggers hormonal changes in their bodies.
OR
We could hypothesize that male deer fight to determine which deer get to mate with the most female deer and pass their genes.
This hypothesis leads to a different answer than the one that is concerned with changes in day length.
THIS answer focues on the adaptive significance of fighting to the deer, that is, on the effect of a particular behavior for reproductive success.
THIS is called an ultimate cause.
What is the reason a particular behavior evolved, in terms of its effect on reproductive success?
Ultimate cause
There has been greater emphasis on understanding the ultimate causes of behavior since 1970.
T/F Behavior is controlled by genetics and not the environment.
False. By both.
When determining to what degree a behavior is more influenced by, what does it depend on?
The particular genes and environment in question.
Genes that control behavior in complex animals, such as vertebrates, typically act on development of the nervous system and musculature–physical traits that evolve through natural selection. The expression of many genes is required for behaviors in animals.
What is a great analogy on how ethologists have identified examples in which the alteration in a single gene may dramatically change a particular behavior?
Baking Cake!
A change in one ingredient (the gene) or the recipe may change the taste (behavior) of the cake, but that does not mean that the one ingredient is responsible for the entire cake.
What is the term used to describe behaviors that seem to be genetically programmed?
Innate (or instinctual)
For example, a spider will spin a specifi cweb without ever seeing a member of its own species build one.
A classic example of innate behavior is the egg-rolling response in geese. If an incubating goose notices an egg out of the nest,she will extend her neck toward the egg, get up, and then roll the eggback to the nest using her beak.
Such behavior functions to improvefi tness because it increases the survival of off spring. Eggs that roll out ofthe nest get cold and fail to hatch. Geese that fail to exhibit the egg-rolling response would pass on fewer of their genes to futuregenerations.
What is an animal behavior that, once initiated, will continue until completed?
Fixed action pattern (FAP)
For example, if the egg is removed while the goose is in theprocess of rolling it back toward the nest, the goose still completes theFAP, as though she were rolling back the now-absent egg to the nest.
What, In animals, a trigger that initiates a fixed action pattern of behavior?
Sign stimulus
The sign stimulus for the goose is thatan egg has rolled out of the nest. According to ethologists, this stimulusacts on the goose’s central nervous system, which provides a neuralstimulus to initiate the motor program, or FAP.
Interestingly, any round object, from a wooden egg to a volleyball, can elicit the egg-rollingresponse. Although sign stimuli usually have certain key components,they are not necessarily very specifi c.
Fun Fact about some behavioral results from simple Genetic Influences:
More recently, in 2004, American neuroscientist Barry Richmondand colleagues showed how the work ethic of monkeys is aff ectedby a gene expressed in a region of the brain called the rhinalcortex. Most primates, humans and monkeys included, tend towork harder when a deadline looms. Richmond’s team trainedfour monkeys to release a lever at the exact moment a spot on acomputer screen changed color from red to green. The monkeyshad to complete this task three times, but only on the third trialdid they receive a food reward, regardless of how they performedon the fi rst two trials. As an indication of how many trials wereleft, the monkeys could see a gray bar on the screen. As the barbecame brighter, the monkeys knew they were reaching the lasttrial, and they worked more diligently for the reward. In the fi rsttwo trials, the monkeys made more errors than in the last trial.Next, the team switched off the gene known to be involved inprocessing reward signals. To do this, the researchers injected ashort strand of DNA into the monkeys’ brains. The effects were only temporary, 10–12 weeks, but during that time the monkeyswere unable to determine how many trials were left before thereward was given, and they worked vigilantly to receive the rewardon every trial, making few errors even on trials one and two.
N/A
What is the ability of an animal to make modifications to a behavior based on previous experience; the process by which new information is acquired?
Learning
What is the form of nonassociative learning in which an organism learns to ignore a repeated stimulus?
Habituation
For example, animals in African safari parks become habituated to the presence of vehiclescontaining tourists; these vehicles are neither a threat nor a benefit to them.
Birds can become habituated to the presence of a scarecrow,resulting in damage to crops. Habituation can be a problem at airports,where birds eventually ignore the alarm calls designed to scare themaway from the runways.
Habituation is a form of nonassociative learning, a change in responseto a repeated stimulus without association with a positive or negative reinforcement.
What is a change in behavior due to the development of an association between a stimulus and a response?
Associative learning
What are the two main types of associative learning?
Classical conditioning and operant conditioning
What is a type of associative learning in which an involuntary response comes to be associated positively or negatively with a stimulus that did not originally elicit the response.
Classical conditioning
This type of learning was investigated by Russian psychologist Ivan Pavlov. In his original experiments in the 1920s, Pavlov restrained a hungry dog in a harness and presented small portions of food at regular intervals.
The dog would salivate whenever it smelled the food. Pavlov then began to sound a metronome when presenting the food. Eventually the dog would salivate at the sound of the metronome, whether or not the food was present.
For example, many insects quickly learn to associate certain flower odors with nectar rewards and other flower odors with no rewards. In humans, the sound of a dentist’s drill is enough to produce a feeling of uneasiness, tension, and sweatypalms.
What is a form of behavior modification; a type of associative learning in which an animal’s behavior is reinforced by a consequence, either a reward or a punishment?
Operant conditioning (aka trial-and-error learning)
The classic example of operant conditioning comes from the work of the American psychologist B. F. Skinner, who placed laboratory animals, usually rats, in a specially devised cage with a lever that came to be known as a Skinner box. If the rat pressed on the lever, a small amount of food would be dispensed. At the beginning of the experiment, the rat would often bump into the lever by accident, eat the food, and continue exploring its cage.
Later, it would learn to associate the lever with obtaining food. Eventually, if it was hungry, the rat would almost continually press the lever.
For example, toadseventually refuse to strike at insects that sting, such as wasps and bees,and birds will learn to avoid bad-tasting butterflies.
In humans, giving children a reward for completing homework is a positive reinforcer.
What’s the difference between operant conditioning and classical conditioning?
In classical conditioning, an involuntary response comes to be associated with a stimulus that did not originally elicit the response, as with Pavlov’s dogs salivating at the sound of a metronome.
What is the ability to solve problems with conscious thought and without direct environmental feedback?
Cognitive learning
This includes activities such as perception, analysis, judgment, recollection, and imagining.
In the 1920s, German psychologist Wolfgang Köhler conducted a series of classic experiments with chimpanzees, and the results suggested that animals other than humans can exhibit cognitive learning. In the experiments, a chimpanzee was left in a room with bananas hanging from the ceiling and out of reach.
Also present in the room were several wooden boxes. At first, the chimp tried in vain to jump up and grab the bananas. After a while, however, it began to arrange the boxes one on top of another underneath the fruit. Eventually, the chimp climbed the boxes and retrieved the fruit.
T/F The behavior we observe in nature is usually a mixture of both innate and learned.
True
Bird songs provide a good example. Many birds learn their songs as juveniles, when they hear their parents sing. If juvenile white-crowned sparrows are raised in isolation, their adult songs do not resemble the typical species-specific song.
Cuckoos lay their eggs in other birds’ nests, sotheir young are reared by parent birds of a diff erent species.However, unlike the white-crowned sparrow, adult cuckoos always sing their own distinctive song, not that of the host species they hear as juveniles. How is this possible?
The ability to sing the same distinctive song must be considered innate behavior because the cuckoo has had no opportunity to learn its song from its parents.
What is a limited period of time during development in which many animals acquire species-specific patterns of behavior?
Critical period
What is learning that occurs during a brief critical period and establishes a long-lasting behavioral response to a specific object or individual, such as recognition and bonding to a parent?
Imprinting
Imprinting was studied by Austrian ethologist Konrad Lorenz in the 1930s. Lorenz noted that young birds of some species imprint on their mother during a critical period that is usually within a few hours after hatching.
This behavior serves them well, because in many species of ducks and geese, it would be hard for the mother to keep track of all her off spring as they walk or swim. After imprinting takes place, the off spring keep track of the mother.
Newborn geese follow the first object they see after hatching and later will follow that particular object only. They normallyfollow their mother but can be induced to imprint on humans. The first thing these young geese saw after hatching was ethologist Konrad Lorenz.
For example, a relatively common trick used in sheep farming is to disguise a lamb whose mother has died or abandoned it by wrapping it in the fleece of another ewe’s stillborn lamb. That second ewe will then care for the abandoned lamb because it smells like her own. In these situations, the innate behavior is the ability to imprint soon after birth, and the factors in the environment are the stimulus to which the imprinting is directed.
[Start 55.2 Local Movement and Long-Range Migration]
What do organisms need to locate locally?
Sources of food, water, mates, and prehaps nesting sites.
