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45.7: Learned Animal Behavior - Biology

45.7: Learned Animal Behavior - Biology


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45.7: Learned Animal Behavior

Chapter Summary

Populations are individuals of a species that live in a particular habitat. Ecologists measure characteristics of populations: size, density, dispersion pattern, age structure, and sex ratio. Life tables are useful to calculate life expectancies of individual population members. Survivorship curves show the number of individuals surviving at each age interval plotted versus time.

45.2 Life Histories and Natural Selection

All species have evolved a pattern of living, called a life history strategy, in which they partition energy for growth, maintenance, and reproduction. These patterns evolve through natural selection they allow species to adapt to their environment to obtain the resources they need to successfully reproduce. There is an inverse relationship between fecundity and parental care. A species may reproduce early in life to ensure surviving to a reproductive age or reproduce later in life to become larger and healthier and better able to give parental care. A species may reproduce once (semelparity) or many times (iteroparity) in its life.

45.3 Environmental Limits to Population Growth

Populations with unlimited resources grow exponentially, with an accelerating growth rate. When resources become limiting, populations follow a logistic growth curve. The population of a species will level off at the carrying capacity of its environment.

45.4 Population Dynamics and Regulation

Populations are regulated by a variety of density-dependent and density-independent factors. Species are divided into two categories based on a variety of features of their life history patterns: r-selected species, which have large numbers of offspring, and K-selected species, which have few offspring. The r- and K-selection theory has fallen out of use however, many of its key features are still used in newer, demographically-based models of population dynamics.

45.5 Human Population Growth

The world’s human population is growing at an exponential rate. Humans have increased the world’s carrying capacity through migration, agriculture, medical advances, and communication. The age structure of a population allows us to predict population growth. Unchecked human population growth could have dire long-term effects on our environment.

45.6 Community Ecology

Communities include all the different species living in a given area. The variety of these species is called species richness. Many organisms have developed defenses against predation and herbivory, including mechanical defenses, warning coloration, and mimicry, as a result of evolution and the interaction with other members of the community. Two species cannot exist in the same habitat competing directly for the same resources. Species may form symbiotic relationships such as commensalism or mutualism. Community structure is described by its foundation and keystone species. Communities respond to environmental disturbances by succession (the predictable appearance of different types of plant species) until a stable community structure is established.

45.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior

Behaviors are responses to stimuli. They can either be instinctual/innate behaviors, which are not influenced by the environment, or learned behaviors, which are influenced by environmental changes. Instinctual behaviors include mating systems and methods of communication. Learned behaviors include imprinting and habituation, conditioning, and, most powerfully, cognitive learning. Although the connection between behavior, genetics, and evolution is well established, the explanation of human behavior as entirely genetic is controversial.


What are some examples of learned behaviors in animals?

Behavior is anything an animal does involving action and/or a response to a stimulus. Blinking, eating, walking, flying, vocalizing and huddling are all examples of behaviors. Behavior is broadly defined as the way an animal acts.

Furthermore, what is an example of imprinting? Other animals that imprint include chicken and geese. The movie Fly Away Home is about imprinting. Sexual imprinting , when an animal learns to distinguish what an appropriate mate looks like to avoid inbreeding, occurs in goats, zebra finches, and pandas.

Herein, what are some examples of learned behaviors in humans?

Let's look into what a learned behavior is. Humans are born with only a few simple behaviors: eat, cry, sleep, poop. These are the instinctual behaviors a baby has as soon as it comes out of the womb. Maybe it's been a year and a half, and your kid is getting bored of crawling.


Key Terms

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    Introduction

    Imagine sailing down a river in a small motorboat on a weekend afternoon the water is smooth and you are enjoying the warm sunshine and cool breeze when suddenly you are hit in the head by a 20-pound silver carp. This is now a risk on many rivers and canal systems in Illinois and Missouri because of the presence of Asian carp.

    This fish—actually a group of species including the silver, black, grass, and big head carp—has been farmed and eaten in China for over 1000 years. It is one of the most important aquaculture food resources worldwide. In the United States, however, Asian carp is considered a dangerous invasive species that disrupts community structure and composition to the point of threatening native species.

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    • Use the information below to generate a citation. We recommend using a citation tool such as this one.
      • Authors: Mary Ann Clark, Matthew Douglas, Jung Choi
      • Publisher/website: OpenStax
      • Book title: Biology 2e
      • Publication date: Mar 28, 2018
      • Location: Houston, Texas
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      Animal Behavior & Learning

      Animals can only be trained to do what they are physically capable of doing. So in order to understand how animal training works, a basic knowledge of animal behavior is very useful.

      Animals can only be trained to do what they are physically capable of doing.

      Definition of Behavior

      Behavior is anything an animal does involving action and/or a response to a stimulus. Blinking, eating, walking, flying, vocalizing and huddling are all examples of behaviors.

      Behavior is broadly defined as the way an animal acts. Swimming is an example of behavior.

      Animals behave in certain ways for four basic reasons:

      • to find food and water
      • to interact in social groups
      • to avoid predators
      • to reproduce

      Behaviors Help Animals Survive

      Animal behaviors usually are adaptations for survival. Some behaviors, such as eating, or escaping predators are obvious survival strategies. But other behaviors, which also are important for survival, may not be as easily understood. For example why does a flamingo stand on one leg? By tucking the other leg close to its body, the bird conserves heat that would otherwise escape.

      By tucking a leg close to its body and standing on the other one, a flamingo conserves heat that would otherwise escape from the exposed leg.

      Ethology is the scientific study of an animal&rsquos behavior in the wild. It is easier to observe and record behavior than to interpret it. When studying animal behavior, observers must take care not to be anthropomorphic &ndash that is, to mistakenly connect human-like characteristics to animals. Although humans and animals share some traits, we have no way of knowing for sure why an animal is doing something.

      Ethology is the scientific study of an animal's behavior in the wild.

      Definition of Stimulus

      A stimulus is a change in the environment that produces a behavioral response. It may be an object or an event perceived through an animal's senses. Stimuli may include the sight of food, the sound of a potential predator, or the smell of a mate. They may also include such daily events as nightfall and seasonal events such as decreasing temperatures. Animals respond to stimuli. Each of these stimuli elicits specific behaviors from animals.

      This opossum responds to a noise stimulus by hiding in the grass.

      Definition of Reflex

      Reflexes are unlearned, involuntary, simple responses to specific stimuli. Reflexes are controlled by the part of the brain called the cerebellum, or primitive brain - animals do not have conscious control over them. Examples of reflexes include shivering in response to the cold, or blinking when an object flies toward the eye.

      Sometimes it is difficult to differentiate between reflexes and complex behavior. Complex behavior may be made up of several reflexes. For example: walking, running, and jumping are all learned behaviors, but they involve several reflexes such as those that control balance.

      Animal Intelligence

      How intelligent are animals? Animals are as intelligent as they need to be to survive in their environment. They often are thought of as intelligent if they can be trained to do certain behaviors. But animals do amazing things in their own habitats. For example, certain octopuses demonstrate complex problem--solving skills. Compared to other invertebrates, octopuses may be quite intelligent. Chimpanzees (Pan troglodytes) are considered to be the most intelligent of the apes because of their ability to identify and construct tools for foraging.

      Accurately rating the intelligence of animals is challenging because it is not standardized. As a result it is difficult to compare intelligences between species. Trying to measure animal intelligence using human guidelines would be inappropriate.

      Chimpanzees are one of the few species that learn to use tools. They learn that when they insert a stick into an ant or termite mound, a favorable result occurs: they can more easily reach the tiny morsels.

      Learned Behavior

      While some animal behaviors are inborn, many are learned from experience. Scientists define learning as a relatively permanent change in behavior as the result of experience. For the most part, learning occurs gradually and in steps.

      An animal&rsquos genetic makeup and body structure determine what kinds of behavior are possible for it to learn. An animal can learn to do only what it is physically capable of doing. A dolphin cannot learn to ride a bicycle, because it has no legs to work the pedals, and no fingers to grasp the handle bars.

      An animal learns and is able to respond and adapt to a changing environment. If an environment changes, an animal's behaviors may no longer achieve results. The animal is forced to change its behavior. It learns which responses get desired results, and changes its behavior accordingly. For purposes of training, an animal trainer manipulates the animal's environment to achieve the desired results.

      Observational Learning

      Animals often learn through observation, that is, by watching other animals. Observational learning can occur with no outside reinforcement. The animal simply learns by observing and mimicking. Animals are able to learn individual behaviors as well as entire behavioral repertoires through observation.

      Observational learning can occur with no outside reinforcement. The animal simply learns through observing and mimicking.

      At SeaWorld, killer whale calves continually follow their mothers and try to imitate everything they do. This includes show behaviors. By a calf's first birthday, it may have learned more than a dozen show behaviors just by mimicking its mother.

      Killer whale calves continually follow their mothers and try to imitate everything they do including show behaviors.

      At Busch Gardens, a young chimpanzee learns foraging and social behavior from watching its mother and other members of the group. Baby black rhinos (Diceros bicornis) are especially close to their mothers. A calf relies on its mother's protection until it is completely weaned. This close tie allows young rhinos to learn defense and foraging behavior.

      Adult animals trained alongside experienced animals may learn a faster rate than if they were trained without them.

      Classical Conditioning

      One of the simplest types of learning is called classical conditioning. Classical conditioning is based on a stimulus (a change in the environment) producing a response from the animal.

      Over time, a response to a stimulus may be conditioned. (Conditioning is another word for learning.) By pairing a new stimulus with a familiar one, an animal can be conditioned to respond to the new stimulus. The conditioned response is typically a reflex - a behavior that requires no thought.

      One of the best known examples of classical conditioning may be Pavlov's experiments on domestic dogs. Russian behaviorist Ivan Pavlov noticed that the smell of meat made his dogs drool. He began to ring a bell just before introducing the meat. After repeating this several times, Pavlov rang the bell without introducing the meat. The dogs drooled when they heard the bell. Over time, they came to associate the sound of the bell with the smell of food. The bell became the stimulus that caused the drooling response.

      Operant Conditioning

      Like classical conditioning, operant conditioning involves a stimulus and a response. But unlike classical conditioning, in operant conditioning the response is a behavior that requires thought and an action. The response is also followed by a consequence known as a reinforcer.

      In operant conditioning, an animal's behavior is conditioned by the consequences that follow. That is, a behavior will happen either more or less often, depending on its results. When an animal performs a particular behavior that produces a favorable result, the animal is likely to repeat the behavior. So, in operant conditioning, an animal is conditioned as it operates on the environment.

      When an animal performs a particular behavior that produces a favorable result, the animal is likely to repeat the behavior.

      Animals learn by the principles of operant conditioning every day. For example, woodpeckers find insects to eat by pecking holes in trees with their beaks. One day, a woodpecker finds a particular tree that offers an especially abundant supply of the bird's favorite bugs. The woodpecker is likely to return to that tree again and again.

      Humans learn by the same principles. We learn that when we push the power button on the remote control, the television comes on. When we put coins into a vending machine, a snack comes out.

      Animal trainers apply the principles of operant conditioning. When an animal performs a behavior that the trainer wants, the trainer administers a favorable consequence.

      Positive Reinforcement

      A favorable consequence is a positive stimulus - something desirable to the animal. When an animal performs a behavior that produces a positive result, the animal is likely to repeat that behavior in the near future.

      The positive result is termed a positive reinforcer because it reinforces, or strengthens the behavior. When a positive reinforcer immediately follows a behavior, it increases the likelihood that the behavior will be repeated. It must immediately follow the behavior in order to be effective.

      Stimulus Discrimination

      As an animal learns behaviors, it also learns the various situations to which they apply. The more behaviors an animal learns, the more it must learn to make distinctions - that is to discriminate - among the situations.

      Discrimination is the tendency for learned behavior to occur in one situation, but not in others. Animals learn which behavior to use for each different stimulus.

      Shaping of Behavior

      Most behaviors cannot be learned all at once, but develop in steps. This step-by-step learning process is called shaping.

      Many human behaviors are learned through shaping. For example, most begin by riding a tricycle. The child graduates to a two-wheeler bicycle with training wheels, and eventually masters a much larger bicycle, perhaps one with multiple speeds. Each step towards the final goal of riding a bicycle is reinforcing.

      Animals learn complex behaviors through shaping. Each step in the learning process is called an approximation. An animal may be reinforced for each successive approximation toward the final goal of the desired trained behavior.

      Animals learn complex behaviors through shaping.

      Extinction of Behavior

      If a behavior is not reinforced, it decreases. Eventually it is extinguished altogether. This is called extinction. Animal trainers use the technique of extinction to eliminate undesired behaviors. (In animal training, when a trainer requests a particular behavior and the animal gives no response, this is also considered an undesired behavior.) To eliminate the behavior, they simply do not reinforce it. Over time, the animal learns that a particular behavior is not producing a desired effect. The animal discontinues the behavior.

      When using the extinction technique, it is important to identify what stimuli are reinforcing for an animal. The trainer must be careful not to present a positive reinforcer after an undesirable behavior. The best way to avoid reinforcing an undesired behavior is to try to give no stimulus at all.


      Imprinting

      If newly-hatched geese are exposed to a moving object of reasonable size and emitting reasonable sounds, they will begin to follow it just as they would normally follow their mother.

      This is called imprinting.

      The time of exposure is quite critical. A few days after hatching, imprinting no longer occurs. Prior to this time, though, the results can be quite remarkable. A gosling imprinted to a moving box or clucking person will try to follow this object for the rest of its life. In fact, when the gosling reaches sexual maturity, it will make the imprinted object &mdash rather than a member of its own species &mdash the goal of its sexual drive.

      Much of our knowledge of imprinting was learned from the research of Konrad Lorenz, shown here with some of his imprinted goslings. Lorenz shared a Nobel Prize in 1973 for his discoveries. (Photo by Tom McAvoy courtesy of LIFE Magazine, ©1955, Time, Inc.)

      Male mice become imprinted with the odor of littermates during the first three weeks of life. When they reach sexual maturity, they avoid mating with close relatives. The odor is controlled by the major histocompatibility complex (MHC).


      Language learning

      The ability to speak was regarded by Descartes as the single most important distinction between humans and other animals, and many modern linguists, most notably Noam Chomsky, have agreed that language is a uniquely human characteristic. Once again, of course, there are problems of definition. Animals of many species undoubtedly communicate with one another. Honeybees communicate the direction and distance of a new source of nectar a male songbird informs rival males of the location of his territory’s boundaries and lets females know of the presence of a territory-owning potential mate vervet monkeys give different calls to signal to other members of the troop the presence of a snake, a leopard, or a bird of prey. None of these naturally occurring examples of communication, however, contains all of the most salient features of human language. In human language, the relationship between a word and its referent is a purely arbitrary and conventional one, which must be learned by anyone wishing to speak that language many words, of course, have no obvious referent at all. Moreover, language can be used flexibly and innovatively to talk about situations that have never yet arisen in the speaker’s experience—or indeed, about situations that never could arise. Finally, the same words in a different order may mean something quite different, and the rules of syntax that dictate this change of meaning are general ones applying to an indefinite number of other sequences of words in the language.

      During the first half of the 20th century, several psychologists bravely attempted to teach human language to chimpanzees. They were uniformly unsuccessful, and it is now known that the structure of the ape’s vocal tract differs in critical ways from that of a human, thus dooming these attempts to failure. Since then, however, several groups of investigators have employed the idea of teaching a nonvocal language to apes. Some have used a gestural sign language widely used by the deaf to communicate with one another others have used plastic tokens that stand for words still others have taught chimpanzees to press symbols on a keyboard. All have had significant success, and several apes have acquired what appears to be a vocabulary of several dozen, and in some cases 100 or 200, “words.”

      Washoe, a female chimpanzee trained by Beatrice and Allan Gardner, learned to use well over 150 signs. Some apparently were used as nouns, standing for people and objects in her daily life, such as the names of her trainers, various kinds of food and drink, clothes, dolls, etc. Others she used as requests, such as please, hurry, and more and yet others as verbs, such as come, go, tickle, and so on. Sarah, the chimpanzee trained by Premack to use plastic tokens as words, also apparently learned to use tokens for nouns, verbs (give, take, put), adjectives (red, round, large), and prepositions (in, under). But do these signs or tokens really function as words? Does the ape using them, or obeying instructions from a trainer who uses them, really understand their meaning? Or is the ape simply performing various arbitrary instrumental responses in the presence of particular stimuli because she had previously been rewarded for doing so?

      There can be little doubt that chimpanzees do have some understanding of what their “words” refer to. Sarah responded appropriately with her token for red if asked the question “What colour of apple?” both when an actual red apple was shown as part of the question and when only the token for an apple (which happened to be a blue triangle) was presented. To Sarah, the blue triangle surely stood for, or was associated with, the red apple. In another study, after two chimpanzees had been taught the meaning of a number of symbols for different kinds of food and different tools, they were able not only to fetch the appropriate but absent object when requested to do so, but they could also sort the symbols into two groups, one for foods and one for tools. In another series of studies, a pygmy chimpanzee named Kanzi demonstrated remarkable linguistic abilities. Unlike other apes, he learned to communicate using keyboard symbols without undergoing long training sessions involving food rewards. Even more impressive, he demonstrated an understanding of spoken English words under rigorous testing conditions in which gestural clues from his trainers were eliminated.

      As noted above, human language is more than a large number of unrelated words: in accordance with certain implicitly understood syntactic rules, humans combine words to form sentences that communicate a more or less complex meaning to a listener. Can apes understand or use sentences? Undoubtedly they can put together several gestures or tokens in a row. A chimpanzee named Lana, who was trained to press symbols on a keyboard, could type out “Please machine give Lana drink” Washoe and other chimpanzees trained in gestural sign language frequently produced strings of gestures such as “You me go out,” “Roger tickle Washoe,” and so on. Skeptical critics, however, have raised doubts about the significance of these strings of signs and symbols. They have pointed out, for example, that when Lana pressed a series of coloured symbols on her keyboard, it was humans who interpreted her actions as the production of a sentence meaning “Please machine give Lana drink.” Might it not be equally reasonable to say that she learned to perform an arbitrary sequence of responses in order to obtain a drink? Pigeons can be trained to press four coloured keys—red, white, yellow, and green—in a particular order to obtain food. Psychologists do not feel any temptation to interpret this behaviour as the production of a sentence. What is it about Lana’s behaviour that requires this richer interpretation?

      In the case of apes trained to use sign language, two other doubts have been raised. First, there is some reason to believe that a disappointingly high proportion of the apes’ gestures may be direct imitations of gestures recently executed by their trainers. Second, a sequence of gestures interpreted as a single sentence is often just as readily interpreted as a number of independent gestures, each prompted, in turn, by a gesture from the trainer. Both these conclusions are based on careful examinations of video recordings of interactions between trainers and apes. Whether they will turn out to be generally true remains an open, and heatedly debated, question.

      Without any explicit training, apes have nevertheless learned to produce strings of two or three signs in certain preferred orders: “more drink” or “give me,” for example, rather than “drink more” or “me give.” Do the animals understand that a string of signs in one order means something different from the same signs in a different order? The following anecdote is suggestive. A chimpanzee called Lucy was accustomed to instructing her trainer, Roger Fouts, by gesturing “Roger tickle Lucy.” One day, instead of complying with this request, Fouts signed back “No, Lucy tickle Roger.” Although at first nonplussed, after several similar exchanges Lucy eventually did as asked. A simple instance of this sort proves little or nothing, but it may suggest what is needed—namely, that Lucy should understand that changing the order of a set of signs alters their meaning in certain predictable ways. She must generalize the rule that the relationship between the meanings of the signs A-B-C and C-B-A (the same signs in reverse order) is similar to the relationship between the meanings of certain other triplets of signs in her vocabulary when their order is reversed.

      The research on language in apes forcefully illustrates a conflict, or tension, that is common to many other areas of research on learning in animals. If the investigators are interested in language and communication, they can attempt to communicate as naturally and informally as possible with their apes. This approach involves treating an ape as a fellow social being, with whom one plays and interacts as far as possible as one would with a human child it also, almost inevitably, results in a style of research where it is exceptionally difficult to control precisely the cues that the ape may be using and even hard to avoid an overly rich, anthropomorphic interpretation of the ape’s behaviour. If, on the other hand, the researchers are interested in rigorous experimental control and economical interpretation of the processes underlying the ape’s performances, they are likely to set the ape formal problems to solve, with rewards for correct responses and no rewards for errors. But such an approach, however scientific it may seem, must run the risk of missing the point. This is not language the investigators are not communicating with the ape in the way they would communicate with a child. The very nature of the experimental problems ensures that the ape will not use its language in the way that a child does: to communicate shared interests, to attract a parent’s attention to what the child has seen or is doing, to comment on a matter of concern to both.

      There is no resolution to this conflict, for both approaches have their virtues as well as their dangers, and both are therefore necessary. In just the same way, the study of a rat pressing a lever in a Skinner box or of a dog salivating to the ticking of a metronome seems to many critics a sterile and narrow approach to animal learning—one that simply misses the point that, if the ability to learn or profit from experience has evolved by natural selection, it must have done so in particular settings or environments because it paid the learner to learn something. It would be foolish to deny this obvious truism: of course it pays animals to learn. Indeed, it may pay them to learn quite particular things in specific situations, and different groups of animals may be particularly adapted to learning rather different things in similar situations. None of this should be forgotten, and the study of such questions requires the scientist to forsake the laboratory for the real world, where animals live and struggle to survive. But few sciences can afford to miss the opportunity to manipulate and experiment under laboratory conditions where this is possible, and none can afford to forget the benefits of precise observation under controlled conditions.


      Innate vs. Learned Behaviors - PowerPoint PPT Presentation

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      The general nature of learning

      Many animals live out their lives following fixed and apparently unvarying routines. Among numerous species of solitary insects, for example, the life cycle consists of the following unvarying events: the females lay their eggs on a particular plant or captured prey the newly hatched larvae immediately start eating and then follow a standard sequence of developmental stages the adults recognize appropriate mates by a set of fixed signs, perform a fixed sequence of mating responses, provision their eggs with suitable nourishment, and finally die before the next generation hatches. The same unchanging sequence is repeated generation after generation. And it is, of course, eminently successful. The same set of responses is invariably elicited by the same set of stimuli, because those responses were, and continue to be, adaptive. Where circumstances do not change, there is little need for an animal’s behaviour to change. Even many aspects of the behaviour of mammals show a similar fixity. A dog withdraws its foot if it is pricked and a young child his hand if burned both people and rabbits blink whenever an object is moved rapidly toward their eyes the feeding behaviour of young infants of virtually all mammalian species consists of sucking elicited by contact with the lips.

      Whenever the same response is always appropriate in a particular circumstance, there is little reason why an animal should need to learn what to do in that circumstance. But the world is not always so stable a place. The food supply that was plentiful yesterday may be exhausted today, and the foraging animal that always returns to the same spot will starve to death. Moreover, a particular food supply may be temporarily depleted but will be replenished if left long enough the successful forager needs to remember where the supply was and when it was last visited, so as to time a return to advantage. In other words, circumstances may change, and the same response is not always appropriate to the same stimuli. Knowing what behaviour is appropriate may depend, therefore, on keeping track of past events.


      Watch the video: Βιολογία Β Γυμνασίου Η στήριξη και η κίνηση στα ζώα (January 2023).