Difference between revisions of "Ethology" - New World Encyclopedia

Revision as of 21:30, 26 June 2007

The egg-rolling behavior of the greylag goose is a widely cited example of a fixed-action pattern, one of the key concepts used by ethologists to explain animal behavior.

Ethology is a branch of zoology concerned with the study of animal behavior. Ethologists take a comparative approach, observing one behavior across a variety of species; studies may include topics such as sexual selection, social behavior, kinship, reciprocity and cooperation, parental investment, conflict and aggression.

Methodologically, ethologists engage in hypothesis-driven experimental investigation, often in the field. This combination of lab work with field study reflects an important conceptual underpinning of the discipline: behavior is assumed to be adaptive; i.e., to have evolved in response to the species’ natural environment.

Ethology emerged as a discrete discipline in the 1920s, through the efforts of Konrad Lorenz, Karl von Frisch, and Niko Tinbergen, who were jointly awarded the 1973 Nobel Prize in Physiology or Medicine for their contributions to the study of behavior. Lorenz, von Frisch, and Tinbergen were in turn influenced by the foundational earlier work of, among others, ornithologists Oskar Heinroth and Julian Huxley and the American myrmecologist William Morton Wheeler, who popularized the term ethology (derived from the Greek word for custom) in a seminal 1902 paper.

One of the key ideas of classical ethology is the concept of fixed action patterns (FAPs). FAPs are instinctive behaviors that will occur reliably in a member of a species in response to an identifiable stimulus from the environment. For example, at the sight of a displaced egg near the next, the greylag goose (Anser anser) will roll the egg back to the others with its beak. If the egg is removed, the animal continues to engage in egg-rolling behavior, pulling its head back as if an imaginary egg is still being maneuvered by the underside of its beak. It will also attempt to move other egg-shaped objects, such as a golf ball, doorknob, or even an egg too large to have been laid by the goose itself (Tinbergen, 1991).

Another important concept is filial imprinting, a form of learning that occurs in young animals, usually during a critical, sensitive period of their lives. During imprinting, a young animal learns to direct some of its social responses to a particular object, usually a parent.

Kelp Gull chicks peck at red spot on their mother's beak to stimulate the regurgitating reflex, another example of a fixed action pattern.

Despite its valuable contributions to the study of animal behavior, classical ethology also spawned problematic general theories about internal control mechanisms and the extent to which they were genetically hardwired (i.e., innate or instinctive). Models of behavior and motivation have since been revised to account for a more flexible (software?) interaction of environment and genetics.

Although ethology as a disciplinary label has largely faded from use, the desire to understand the animal world has made ethology's intellectual inheritors – such as behavioral ecology and evolutionary psychology – rapidly growing fields. Today, students of animal behavior tend to place greater emphasis on social relationships (rather than the animal as individual); however, these studies retain ethology’s tradition of fieldwork and its grounding in evolutionary theory.

Methodology

Tinbergen's four questions for ethologists

The practice of ethological investigation is grounded in the scientific method of hypothesis-driven experimentation. Lorenz's collaborator, Niko Tinbergen, argued that ethologists should consider the following four categories when attempting to formulate a hypothesis that explains any instance of behavior:

Function: how does the behavior impact the animal's chance of survival and reproduction?
Mechanism: what are the stimuli that elicit the response? How has the response been modified by recent learning?
Development: how does the behavior change with age? What early experiences are necessary for the behavior to be demonstrated?
Evolutionary history: how does the behavior compare with similar behavior in related species? How might the behavior have arisen through the process of phylogeny (the development of the species, genus, or group)?

Using fieldwork to test hypotheses

As an example of how an ethologist might approach a question about animal behavior, consider the study of hearing in an echolocating bat. A species of bat may use frequency chirps to probe the environment while in flight. A traditional neuroscientific study of the auditory system of the bat would involve anesthetizing it, performing a craniotomy to insert recording electrodes in its brain, and then recording neural responses to pure tone stimuli played from loudspeakers. In contrast, an ideal ethological study would attempt to replicate the natural conditions of the animal as closely as possible. It would involve recording from the animal’s brain while it is awake, producing its natural calls while performing a behavior such as insect capture.

Key principles and concepts

Behaviors are adaptive responses to natural selection

Because ethology is understood as a branch of biology, ethologists have been particularly concerned with the evolution of behavior and the understanding of behavior in terms of the theory of natural selection. In one sense, the first modern ethologist was Charles Darwin, whose book The Expression of the Emotions in Man and Animals (1872) has influenced many ethologists. (Darwin’s protégé George Romanes became one of the founders of comparative psychology, positing a similarity of cognitive processes and mechanisms between animals and humans.)

Animals use fixed action patterns in communication

The honeybee's figure-eight dance is a fixed-action pattern that communicates information to other members of the group: the angle from the sun indicates the direction of a food source; the duration signifies its distance.

As mentioned above, a fixed action pattern (FAP) is an instinctive behavioral sequence produced by a neural network known as the innate releasing mechanism in response to an external sensory stimulus called the sign stimulus or releaser. Once identified by ethologists, FAPs can be compared across species, contrasting similarities and differences in behavior to similarities and differences in form (morphology).

An example of how FAPs work in animal communication is the classic investigation by Austrian ethologist Karl von Frisch of the so-called "dance language" underlying bee communication. The dance is a mechanism for successful foragers to recruit members of the colony to new sources of nectar or pollen.

Imprinting is a behavior involved in learning

Imprinting describes any kind of phase-sensitive learning (i.e., learning occurring at a particular age or life stage) that is rapid and apparently independent of the consequences of behavior. It was first used to describe situations in which an animal or person learns the characteristics of some stimulus, which is therefore said to be "imprinted" onto the subject.

The best known form of imprinting is filial imprinting, in which a young animal learns the characteristics of its parent. Lorenz observed that the young of birds such as geese and chickens spontaneously followed their mothers from almost the first day after they were hatched. Lorenz demonstrated how incubator-hatched geese would imprint on the first suitable moving stimulus they saw within what he called a "critical period" of about 36 hours shortly after hatching. Most famously, the goslings would imprint on Lorenz himself (more specifically, on his wading boots).

File:Lorenz.gif

Konrad Z. Lorenz being followed by his imprinted geese.

Sexual imprinting, which occurs at a later stage of development, is the process by which a young animal learns the characteristics of a desirable mate. For example, male zebra finches appear to prefer mates with the appearance of the female bird that rears them, rather than mates of their own type (Immelmann, 1972).Reverse sexual imprinting is also seen: when two individuals live in close domestic proximity during their early years, both are desensitized to later close sexual attraction and capture-bonding. This phenomenon, known as the Westermarck effect, has probably evolved to suppress inbreeding.

Relation to comparative psychology

In order to summarize the concepts and methods that underlie ethological study, it might be helpful to compare classical ethology to early work in comparative psychology, an alternative approach to the study of animal behavior that also emerged in the early 20th century. The rivalry between these two fields stemmed in part from the disciplinary politcs of academia: ethology, which had developed in Europe, failed to gain a strong foothold in North America, where comparative psychology was dominant.

Broadly speaking, comparative psychology studies general processes, while ethology focuses on adaptive specialization. The two approaches are complementary rather than competitive, but they do lead to different perspectives and sometimes to conflicts of opinion about matters of substance:

Comparative psychology construes its study as a branch of psychology rather than as an outgrowth of biology. Thus, where comparative psychology sees the study of animal behavior in the context of what is known about human psychology, ethology situates animal behavior in the context of what is known about animal anatomy, physiology, neurobiology, and phylogenetic history.
Comparative psychologists are interested more in similarities than differences in behavior; they are seeking general laws of behavior, especially relating to development, which could be applied to all animal species, including humans. Hence, early comparative psychologists concentrated on gaining extensive knowledge of the behavior of a handful of species, while ethologists were more interested in gaining knowledge of behavior in a wide range of species in order to be able to make principled comparisons across taxonomic groups.
Ethologists focus primarily on lab experiments involving a handful of species, mainly rats and pigeons, whereas ethologists concentrated on behavior in natural situations.

Since the 1970s, however, animal behavior has become an integrated discipline, with comparative psychologists and ethological animal behaviorists working on similar problems and publishing side by side in the same journals.

Recent developments in the field

In 1970, the English ethologist John H. Crook published an important paper in which he distinguished comparative ethology from social ethology. He argued that the ethological studies published to date had focused on the former approach—looking at animals as individuals—whereas in the future ethologists would need to concentrate on the social behavior of animal groups.

Since the appearance of E. O. Wilson's seminal book Sociobiology: The New Synthesis in1975, ethology has indeed been much more concerned with the social aspects of behavior, such as phenotypic altruism and cooperation. Research has also been driven by a more sophisticated version of evolutionary theory associated with Wilson and Richard Dawkins.

Furthermore, a substantial rapprochement with comparative psychology has occurred, so the modern scientific study of behavior offers a more or less seamless spectrum of approaches – from animal cognition to more traditional comparative psychology, ethology, and behavioral ecology. Evolutionary psychology, an extension of behavioral ecology, looks at commonalities of cognitive processes in humans and other animals as we might expect natural selection to have shaped them. Another promising subfield is neuroethology, concerned with how the structure and functioning of the brain controls behavior and makes learning possible.

List of influential ethologists

The following list represents a survey of scientists who have made notable contributions to the field of ethology (many are comparative psychologists):

Robert Ardrey
George Barlow
Patrick Bateson
John Bowlby
Colleen Cassady St. Clair
Raymond Coppinger
John H. Crook
Marian Stamp Dawkins
Richard Dawkins
Irenäus Eibl-Eibesfeldt
John Fentress
Dian Fossey

Karl von Frisch
Jane Goodall
Oskar Heinroth
Robert Hinde
Julian Huxley
Lynne Isbell
Julian Jaynes
Erich Klinghammer
Peter Klopfer
Otto Koehler
Paul Leyhausen
Konrad Lorenz

Aubrey Manning
Eugene Marais
Patricia McConnell
Desmond Morris
George Romanes
B. F. Skinner
William Homan Thorpe
Niko Tinbergen
Jakob von Uexküll
Frans de Waal
William Morton Wheeler
E. O. Wilson

References
ISBN links support NWE through referral fees

Barnard, C. 2004. Animal Behaviour: Mechanism, Development, Function and Evolution. Harlow, England: Pearson/Prentice Hall. ISBN 0-130-89936-4
Tinbergen, N. 1991. The Study of Instinct. Reprint ed. New York: Oxford University Press. ISBN 0-198-57722-2

External links

Most popular Internet platform for animal behaviour
Konrad Lorenz Institute for Evolution and Cognitive Research (KLI)
Center for the Integrative Study of Animal behaviour (CISAB)
Introduction to ethology
Applied Ethology
The International Society for Human Ethology - aims at promoting ethological perspectives in the scientific study of humans worldwide
The Four Areas of Biology
The Four Areas of Biology AND levels of inquiry

Credits

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@@ Line 1: / Line 1: @@
 {{Claimed}}{{Contracted}}
-  [[Image:V31-d-Graugans.JPG|right|thumb|The egg-rolling behavior of the greylag goose is a widely cited example of a ''fixed-action pattern'', one of the key concepts used by ethologists to explain animal behavior.]]
+  [[Image:V31-d-Graugans.JPG|right|thumb|175px|The egg-rolling behavior of the greylag goose is a widely cited example of a ''fixed-action pattern'', one of the key concepts used by ethologists to explain animal behavior.]]
-'''Ethology''' is a branch of [[zoology]] concerned with the study of [[animal]] [[behavior]]. Ethologists study a range of animal behaviors including sexual selection, social behavior, kinship, reciprocity and cooperation, parental investment, conflict and aggression. (comparative approach – usually studies one behavior comparatively across a variety of species)
+'''Ethology''' is a branch of [[zoology]] concerned with the study of [[animal]] [[behavior]]. Ethologists take a comparative approach, observing one behavior across a variety of species; studies may include topics such as sexual selection, social behavior, kinship, reciprocity and cooperation, parental investment, conflict and aggression.
-Methodologically, ethologists engage in hypothesis-driven experimental investigation, often in the field. This combination of lab work with field study reflects an important underpinning of the discipline: behavior is assumed to be adaptive to the species’ natural environment. (Only animals have nervous systems, with their implications for perception, coordination, orientation, learning, and memory)
+Methodologically, ethologists engage in hypothesis-driven experimental investigation, often in the field. This combination of lab work with field study reflects an important conceptual underpinning of the discipline: behavior is assumed to be ''adaptive''; i.e., to have evolved in response to the species’ natural environment.
-Ethology emerged as a discrete discipline in the 1920s; its founding practitioners, themselves influenced by the German ornithologist [[Oskar Heinroth]], were [[Konrad Lorenz]], [[Karl von Frisch]], and [[Niko Tinbergen]], who were jointly awarded the 1973 [[Nobel Prize in Physiology or Medicine]] for their contributions to the study of behavior. (maybe construe them as popularizers and synthesizers of foundational earlier work of Douglas Spalding, Heinroth, C. Lloyd Morgan, Herbert Spencer Jennings, et al.)
+Ethology emerged as a discrete discipline in the 1920s, through the efforts of [[Konrad Lorenz]], [[Karl von Frisch]], and [[Niko Tinbergen]], who were jointly awarded the 1973 [[Nobel Prize in Physiology or Medicine]] for their contributions to the study of behavior. Lorenz, von Frisch, and Tinbergen were in turn influenced by the foundational earlier work of, among others, ornithologists [[Oskar Heinroth]] and [[Julian Huxley]] and the American [[myrmecologist]] [[William Morton Wheeler]], who popularized the term ''ethology'' (derived from the Greek word for ''custom'') in a seminal 1902 paper.
-One of the key ideas of classical ethology is the concept of [[fixed action pattern]]s (FAPs). FAPs are instinctive behaviors that will occur reliably in a member of a species in response to an identifiable stimulus from the environment. For example, at the sight of a displaced [[Egg (biology)|egg]] near the next, the greylag goose will roll the egg back to the others with its beak. If the egg is removed, the animal continues to engage in egg-rolling behavior, pulling its head back as if an imaginary egg is still being maneuvered by the underside of its beak. It will also attempt to move other egg-shaped objects, such as a golf ball, doorknob, or even an egg too large to have been laid by the goose itself (Tinbergen, 1991).
+*One of the key ideas of classical ethology is the concept of [[fixed action pattern]]s (FAPs). FAPs are instinctive behaviors that will occur reliably in a member of a species in response to an identifiable stimulus from the environment. For example, at the sight of a displaced [[Egg (biology)|egg]] near the next, the greylag goose (''Anser anser'') will roll the egg back to the others with its beak. If the egg is removed, the animal continues to engage in egg-rolling behavior, pulling its head back as if an imaginary egg is still being maneuvered by the underside of its beak. It will also attempt to move other egg-shaped objects, such as a golf ball, doorknob, or even an egg too large to have been laid by the goose itself (Tinbergen, 1991).
-Classical ethology spawned problematic grand theories about internal control mechanisms and the extent to which they were genetically hardwired (''innate'' or ''instinctive'', according to the terminology). (what do we think today that's different – a model that has since been revised to do xyz)
+*Another important concept is ''filial imprinting'', a form of learning that occurs in young animals, usually during a critical, sensitive period of their lives. During imprinting, a young animal learns to direct some of its social responses to a particular object, usually a parent.
-Although ''ethology'' as a disciplinary label has largely faded from use, the desire to understand the animal world has made ethology's intellectual inheritors – such as [[behavioral ecology]] and [[evolutionary psychology]] – rapidly growing fields. Today, students of animal behavior tend to place greater emphasis on social relationships (rather than the individual as variable); however, these studies retain ethology’s tradition of hypothesis-driven investigation and its grounding in evolutionary theory.
+[[Image:Larus_Dominicanus.jpg|left|thumb|180px|[[Kelp Gull]] chicks peck at red spot on their mother's beak to stimulate the regurgitating reflex, another example of a fixed action pattern.]]
-==Relation to comparative psychology==
+Despite its valuable contributions to the study of animal behavior, classical ethology also spawned problematic general theories about internal control mechanisms and the extent to which they were genetically hardwired (i.e., ''innate'' or ''instinctive''). Models of behavior and motivation have since been revised to account for a more flexible (software?) interaction of environment and genetics.
-In order to illuminate the concepts and methods that underlie ethological study, it might be helpful to compare classical ethology to early work in [[comparative psychology]], an alternative approach to the study of animal behavior:
+Although ''ethology'' as a disciplinary label has largely faded from use, the desire to understand the animal world has made ethology's intellectual inheritors – such as [[behavioral ecology]] and [[evolutionary psychology]] – rapidly growing fields. Today, students of animal behavior tend to place greater emphasis on social relationships (rather than the animal as individual); however, these studies retain ethology’s tradition of fieldwork and its grounding in evolutionary theory.
-*Comparative psychology construes its study as a branch of [[psychology]] rather than as an outgrowth of [[biology]]. Thus, where comparative psychology sees the study of animal behavior in the context of what is known about human psychology, ethology situates animal behavior in the context of what is known about animal [[anatomy]], [[physiology]], [[neurobiology]], and [[phylogenetic]] history.
-*Comparative psychologists are interested more in similarities than differences in behavior; they are seeking general laws of behavior, especially relating to development, which could be applied to all animal species, including humans. Hence, early comparative psychologists concentrated on gaining extensive knowledge of the behavior of a handful of [[species]], while ethologists were more interested in gaining knowledge of behavior in a wide range of species in order to be able to make principled comparisons across [[alpha taxonomy|taxonomic]] groups.
-*Ethologists focus primarily on lab experiments involving a handful of species, mainly rats and pigeons, whereas ethologists concentrated on behavior in natural situations.
-In sum, comparative psychology studies general processes, while ethology focuses on adaptive specialization. The two approaches are complementary rather than competitive, but they do lead to different perspectives and sometimes to conflicts of opinion about matters of substance. In addition, for most of the [[twentieth century]], ethology, which had developed in Europe, failed to gain a strong foothold in [[North America]], where comparative psychology was dominant. Since the 1970s, animal behavior has become an integrated discipline, with comparative psychologists and ethological animal behaviorists working on similar problems and publishing side by side in the same journals.
 ==Methodology==
@@ Line 33: / Line 30: @@
 ===Using fieldwork to test hypotheses===
-As an example of how an ethologist might approach a question about animal behavior, consider the study of [[hearing]] in an [[echolocating bat]]. A species of bat may use frequency chirps to probe the environment while in flight. A traditional neuroscientific study of the [[auditory system]] of the bat would involve [[Anesthesia|anesthetizing]] it, performing a [[craniotomy]] to insert [[Electrophysiology#Electrophysiology_-_the_techniques|recording electrodes]] in its [[brain]], and then recording [[action potential|neural responses]] to pure [[pitch (music)|tone]] [[stimulus (physiology)|stimuli]] played from [[loudspeakers]]. In contrast, an ideal ethological study would attempt to replicate the natural conditions of the animal as closely as possible. It would involve recording from the animal’s brain while it is [[awake]], producing its natural calls while performing some natural behavior such as insect capture.
+As an example of how an ethologist might approach a question about animal behavior, consider the study of [[hearing]] in an [[echolocating bat]]. A species of bat may use frequency chirps to probe the environment while in flight. A traditional neuroscientific study of the [[auditory system]] of the bat would involve [[Anesthesia|anesthetizing]] it, performing a [[craniotomy]] to insert [[Electrophysiology#Electrophysiology_-_the_techniques|recording electrodes]] in its [[brain]], and then recording [[action potential|neural responses]] to pure [[pitch (music)|tone]] [[stimulus (physiology)|stimuli]] played from [[loudspeakers]]. In contrast, an ideal ethological study would attempt to replicate the natural conditions of the animal as closely as possible. It would involve recording from the animal’s brain while it is [[awake]], producing its natural calls while performing a behavior such as insect capture.
 ==Key principles and concepts==
 ===Behaviors are adaptive responses to natural selection===
-Because ethology is understood as a branch of biology, ethologists have been particularly concerned with the [[evolution]] of behavior and the understanding of behavior in terms of the theory of [[natural selection]].  In one sense, the first modern ethologist was [[Charles Darwin]], whose book ''The Expression of the Emotions in Man and Animals'' (1872) has influenced many ethologists. (Darwin’s protégé [[George Romanes]] became one of the founders of comparative psychology, positing a similarity of cognitive processes and mechanisms between animals and humans.) need another sentence ab. Evolutionary underpinnings.
+Because ethology is understood as a branch of biology, ethologists have been particularly concerned with the [[evolution]] of behavior and the understanding of behavior in terms of the theory of [[natural selection]].  In one sense, the first modern ethologist was [[Charles Darwin]], whose book ''The Expression of the Emotions in Man and Animals'' (1872) has influenced many ethologists. (Darwin’s protégé [[George Romanes]] became one of the founders of comparative psychology, positing a similarity of cognitive processes and mechanisms between animals and humans.)
 ===Animals use fixed action patterns in communication===
-[[Image:Bee dance.png|thumb|left|200px|The honeybee's figure-eight dance is a fixed-action pattern that communicates information to other members of the group: the angle from the sun indicates the direction of a food source; the duration of the dance signifies its distance.]]
+[[Image:Bee dance.png|thumb|left|175px|The honeybee's figure-eight dance is a fixed-action pattern that communicates information to other members of the group: the angle from the sun indicates the direction of a food source; the duration signifies its distance.]]
 As mentioned above, a ''fixed action pattern (FAP)'' is an [[instinct]]ive [[behavior]]al sequence produced by a [[biological neural network|neural network]] known as the ''innate releasing mechanism'' in response to an external [[sensory system|sensory]] stimulus called the ''sign stimulus'' or ''releaser''. Once identified by ethologists, FAPs can be compared across species, contrasting similarities and differences in behavior to similarities and differences in form ([[morphology (biology)|morphology]]).
@@ Line 47: / Line 44: @@
 ===Imprinting is a behavior involved in learning===
-[[Image:Lorenz.gif|thumb|right|200px|Konrad Z. Lorenz being followed by his imprinted geese]]
 ''Imprinting'' describes any kind of phase-sensitive [[learning]] (i.e., learning occurring at a particular age or life stage) that is rapid and apparently independent of the consequences of behavior.  It was first used to describe situations in which an animal or person learns the characteristics of some stimulus, which is therefore said to be "imprinted" onto the subject.
 The best known form of imprinting is ''filial imprinting'', in which a young animal learns the characteristics of its parent.  Lorenz observed that the young of birds such as [[goose|geese]] and [[chicken]]s spontaneously followed their mothers from almost the first day after they were hatched. Lorenz demonstrated how incubator-hatched geese would imprint on the first suitable moving stimulus they saw within what he called a "[[critical period]]" of about 36 hours shortly after hatching.  Most famously, the goslings would imprint on Lorenz himself (more specifically, on his wading boots).
-Something on sexual imprinting, which occurs at a later stage? '''Sexual imprinting''' is the process by which a young animal learns the characteristics of a desirable mate. For example, male [[zebra finch]]es appear to prefer mates with the appearance of the female bird that rears them, rather than mates of their own type (Immelmann, 1972).
+[[Image:Lorenz.gif|thumb|right|200px|Konrad Z. Lorenz being followed by his imprinted geese.]]
-''Reverse'' sexual imprinting is also seen: when two people live in close domestic proximity during the first few years in the life of either one, both are desensitized to later close [[sexual attraction]] and [[capture-bonding]]. This phenomenon, known as the '''Westermarck effect''', was first formally described by [[anthropologist]] [[Edvard Westermarck]].  The Westermarck effect has since been observed in many places and cultures, including in the [[Israel]]i [[kibbutz]] system, and the Chinese [[Shim-pua marriage]] customs, as well as in biological-related families.
+''Sexual imprinting'', which occurs at a later stage of development, is the process by which a young animal learns the characteristics of a desirable mate. For example, male [[zebra finch]]es appear to prefer mates with the appearance of the female bird that rears them, rather than mates of their own type (Immelmann, 1972).''Reverse'' sexual imprinting is also seen: when two individuals live in close domestic proximity during their early years, both are desensitized to later close [[sexual attraction]] and [[capture-bonding]]. This phenomenon, known as the ''Westermarck effect,'' has probably evolved to suppress [[inbreeding]].
-In the case of the Israeli [[kibbutz]] farms, children were reared somewhat communally in peer groups - groups based on age, not biological relation. A study of the marriage patterns of these children later in life revealed that out of the nearly 3,000 marriages that occurred across the kibbutz system, only fourteen were between children from the same peer group. Of those fourteen, none had been reared together during the first six years of life. This result provides evidence not only that the Westermarck effect is demonstrable, but that it operates during the critical period from birth to the age of six (Shepher, 1983).
+==Relation to comparative psychology==
+In order to summarize the concepts and methods that underlie ethological study, it might be helpful to compare classical ethology to early work in [[comparative psychology]], an alternative approach to the study of animal behavior that also emerged in the early 20th century. The rivalry between these two fields stemmed in part from the disciplinary politcs of academia: ethology, which had developed in Europe, failed to gain a strong foothold in [[North America]], where comparative psychology was dominant.
-When close proximity during this critical period does not occur - for example, where a brother and sister are brought up separately, never meeting one another - they may find one another highly sexually attractive when they meet as adults. This observation is consistent with the theory that the Westermarck effect evolved to suppress [[inbreeding]].
+Broadly speaking, comparative psychology studies general processes, while ethology focuses on adaptive specialization. The two approaches are complementary rather than competitive, but they do lead to different perspectives and sometimes to conflicts of opinion about matters of substance:
+*Comparative psychology construes its study as a branch of [[psychology]] rather than as an outgrowth of [[biology]]. Thus, where comparative psychology sees the study of animal behavior in the context of what is known about human psychology, ethology situates animal behavior in the context of what is known about animal [[anatomy]], [[physiology]], [[neurobiology]], and [[phylogenetic]] history.
+*Comparative psychologists are interested more in similarities than differences in behavior; they are seeking general laws of behavior, especially relating to development, which could be applied to all animal species, including humans. Hence, early comparative psychologists concentrated on gaining extensive knowledge of the behavior of a handful of [[species]], while ethologists were more interested in gaining knowledge of behavior in a wide range of species in order to be able to make principled comparisons across [[alpha taxonomy|taxonomic]] groups.
+*Ethologists focus primarily on lab experiments involving a handful of species, mainly rats and pigeons, whereas ethologists concentrated on behavior in natural situations.
+Since the 1970s, however, animal behavior has become an integrated discipline, with comparative psychologists and ethological animal behaviorists working on similar problems and publishing side by side in the same journals.
 ==Recent developments in the field==
-In [[1970]], the [[England|English]] ethologist John H. Crook published an important paper in which he distinguished '''comparative ethology''' from '''social ethology'''. He argued that the ethological studies published to date had focused on the former approach—looking at animals as individuals—whereas in the future ethologists would need to concentrate on the social behavior of animal groups.
+In 1970, the [[England|English]] ethologist John H. Crook published an important paper in which he distinguished ''comparative ethology'' from ''social ethology''. He argued that the ethological studies published to date had focused on the former approach—looking at animals as individuals—whereas in the future ethologists would need to concentrate on the social behavior of animal groups.
 Since the appearance of [[E. O. Wilson]]'s seminal book ''[[Sociobiology: The New Synthesis]]'' in1975, ethology has indeed been much more concerned with the social aspects of behavior, such as phenotypic altruism and cooperation. Research has also been driven by a more sophisticated version of evolutionary theory associated with Wilson and [[Richard Dawkins]].
-Furthermore, a substantial rapprochement with comparative psychology has occurred, so the modern scientific study of behavior offers a more or less seamless spectrum of approaches – from animal cognition to more traditional comparative psychology, ethology, and behavioral ecology. Evolutionary psychology, an extension of behavioral ecology, looks at commonalities of cognitive processes in humans and other animals as we might expect natural selection to have shaped them.
+Furthermore, a substantial rapprochement with comparative psychology has occurred, so the modern scientific study of behavior offers a more or less seamless spectrum of approaches – from animal cognition to more traditional comparative psychology, ethology, and behavioral ecology. ''Evolutionary psychology'', an extension of behavioral ecology, looks at commonalities of cognitive processes in humans and other animals as we might expect natural selection to have shaped them. Another promising subfield is ''neuroethology'', concerned with how the structure and functioning of the brain controls behavior and makes learning possible.
-==History of the term==
-The term "ethology" is derived from the [[Greek language|Greek]] word "[[ethos]]" (''ήθος''), meaning "[[convention (norm)|custom]]." Other words derived from the Greek word "ethos" include "ethics" and "ethical." The term was first popularized in English by the American [[myrmecologist]] [[William Morton Wheeler]] in 1902.  An earlier, slightly different sense of the term was proposed by [[John Stuart Mill]] in his 1843 <cite>System of Logic</cite>.  He recommended the development of a new science, "ethology," whose purpose would be the explanation of individual and national differences in character, on the basis of [[associationism|associationistic]] [[psychology]].  This use of the word for this purpose was never adopted.
 ==List of influential ethologists==
@@ Line 119: / Line 118: @@
 *Barnard, C. 2004. ''Animal Behaviour: Mechanism, Development, Function and Evolution''. Harlow, England: Pearson/Prentice Hall. ISBN 0-130-89936-4
 *Tinbergen, N. 1991. ''The Study of Instinct''. Reprint ed. New York: Oxford University Press. ISBN 0-198-57722-2
-*might need to add refs from inbreeding section
 ==Further reading==