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Saturday, July 31, 2021

Konrad Lorenz

From Wikipedia, the free encyclopedia
 
Konrad Lorenz

Konrad Lorenz.JPG
Born
Konrad Zacharias Lorenz

7 November 1903
Died27 February 1989 (aged 85)
Vienna, Austria
NationalityAustrian
Awards
Scientific career
FieldsEthology

Konrad Zacharias Lorenz (German pronunciation: [ˈkɔnʁaːt ˈloːʁɛnts] (About this soundlisten); 7 November 1903 – 27 February 1989) was an Austrian zoologist, ethologist, and ornithologist. He shared the 1973 Nobel Prize in Physiology or Medicine with Nikolaas Tinbergen and Karl von Frisch. He is often regarded as one of the founders of modern ethology, the study of animal behavior. He developed an approach that began with an earlier generation, including his teacher Oskar Heinroth.

Lorenz studied instinctive behavior in animals, especially in greylag geese and jackdaws. Working with geese, he investigated the principle of imprinting, the process by which some nidifugous birds (i.e. birds that leave their nest early) bond instinctively with the first moving object that they see within the first hours of hatching. Although Lorenz did not discover the topic, he became widely known for his descriptions of imprinting as an instinctive bond. In 1936 he met Tinbergen, and the two collaborated in developing ethology as a separate sub-discipline of biology. A Review of General Psychology survey, published in 2002, ranked Lorenz the 65th most cited scholar of the 20th century in the technical psychology journals, introductory psychology textbooks, and survey responses.

Lorenz's work was interrupted by the onset of World War II and in 1941 he was recruited into the German Army as a medic. In 1944, he was sent to the Eastern Front where he was captured by the Soviet Red Army and spent four years as a German prisoner of war in Soviet Armenia. After the war, he regretted his membership of the Nazi Party.

Lorenz wrote numerous books, some of which, such as King Solomon's Ring, On Aggression, and Man Meets Dog, became popular reading. His last work "Here I Am – Where Are You?" is a summary of his life's work and focuses on his famous studies of greylag geese.

Biography

Lorenz in 1904 with his elder brother

Lorenz was the son of Adolf Lorenz, a wealthy and distinguished surgeon, and his wife Emma (née Lecher), a physician who had been her husband's assistant. The family lived on a large estate at Altenburg, and had a city apartment in Vienna.

In his autobiographical essay, published in 1973 in Les Prix Nobel (winners of the prizes are requested to provide such essays), Lorenz credits his career to his parents, who "were supremely tolerant of my inordinate love for animals", and to his childhood encounter with Selma Lagerlöf's The Wonderful Adventures of Nils, which filled him with a great enthusiasm about wild geese."

At the request of his father, Adolf Lorenz, he began a premedical curriculum in 1922 at Columbia University, but he returned to Vienna in 1923 to continue his studies at the University of Vienna. He graduated as Doctor of Medicine (MD) in 1928 and became an assistant professor at the Institute of Anatomy until 1935. He finished his zoological studies in 1933 and received his second doctorate (PhD).

While still a student, Lorenz began developing what would become a large menagerie, ranging from domestic to exotic animals. In his popular book King Solomon's Ring, Lorenz recounts that while studying at the University of Vienna he kept a variety of animals at his parents' apartment, ranging from fish to a capuchin monkey named Gloria.

In 1936, at an international scientific symposium on instinct, Lorenz met his great friend and colleague Nikolaas Tinbergen. Together they studied geese—wild, domestic, and hybrid. One result of these studies was that Lorenz "realized that an overpowering increase in the drives of feeding as well as of copulation and a waning of more differentiated social instincts is characteristic of very many domestic animals". Lorenz began to suspect and fear "that analogous processes of deterioration may be at work with civilized humanity." This observation of bird hybrids caused Lorenz to believe that domestication resulting from urbanisation in humans might also cause dysgenic effects, and to argue in two papers that the Nazi eugenics policies against this were therefore scientifically justified.

Lorenz as a Soviet POW in 1944

In 1940 he became a professor of psychology at the University of Königsberg. He was drafted into the Wehrmacht in 1941. He sought to be a motorcycle mechanic, but instead he was assigned as a military psychologist, conducting racial studies on humans in occupied Poznań under Rudolf Hippius. The objective was to study the biological characteristics of "German-Polish half-breeds" to determine whether they 'benefitted' from the same work ethics as 'pure' Germans. The degree to which Lorenz participated in the project is unknown, but the project director Hippius referred a couple of times to Lorenz as an "examining psychologist".

Lorenz later described that he once saw transports of concentration camp inmates at Fort VII near Poznań, which made him "fully realize the complete inhumanity of the Nazis".

He was sent to the Russian front in 1944 where he quickly became a prisoner of war in the Soviet Union from 1944 to 1948. In captivity in Soviet Armenia, he continued to work as a medic and "became tolerably fluent in Russian and got quite friendly with some Russians, mostly doctors." When he was repatriated, he was allowed to keep the manuscript of a book he had been writing, and his pet starling. He arrived back in Altenberg (his family home, near Vienna) both "with manuscript and bird intact." The manuscript became his 1973 book Behind the Mirror.

The Max Planck Society established the Lorenz Institute for Behavioral Physiology in Buldern, Germany, in 1950. In his memoirs Lorenz described the chronology of his war years differently from what historians have been able to document after his death. He himself claimed that he was captured in 1942, where in reality he was only sent to the front and captured in 1944, leaving out entirely his involvement with the Poznań project.

In 1958, Lorenz transferred to the Max Planck Institute for Behavioral Physiology in Seewiesen. He shared the 1973 Nobel Prize in Physiology or Medicine "for discoveries in individual and social behavior patterns" with two other important early ethologists, Nikolaas Tinbergen and Karl von Frisch. In 1969, he became the first recipient of the Prix mondial Cino Del Duca. He was a friend and student of renowned biologist Sir Julian Huxley (grandson of "Darwin's bulldog", Thomas Henry Huxley). Famed psychoanalyst Ralph Greenson and Sir Peter Scott were good friends. Lorenz and Karl Popper were childhood friends; many years after they met, during the celebration of Popper's 80 years, they wrote together a book entitled Die Zukunft ist offen.

He retired from the Max Planck Institute in 1973 but continued to research and publish from Altenberg and Grünau im Almtal in Austria. He died on 27 February 1989 in Altenberg.

Personal life

Lorenz married his childhood friend, Margarethe Gebhardt, a gynaecologist, daughter of a market gardener who lived near the Lorenz family; they had a son and two daughters. He lived at the Lorenz family estate, which included a "fantastical neo-baroque mansion", previously owned by his father.

Ethology

Lorenz is recognized as one of the founding fathers of the field of ethology, the study of animal behavior. He is best known for his discovery of the principle of attachment, or imprinting, through which in some species a bond is formed between a newborn animal and its caregiver. This principle had been discovered by Douglas Spalding in the 19th century, and Lorenz's mentor Oskar Heinroth had also worked on the topic, but Lorenz's description of Prägung, imprinting, in nidifugous birds such as greylag geese in his 1935 book Der Kumpan in der Umwelt des Vogels ("The Companion in the Environment of Birds") became the foundational description of the phenomenon.

Here, Lorenz used Jakob von Uexküll's concept of Umwelt to understand how the limited perception of animals filtered out certain phenomena with which they interacted instinctively. For example, a young goose instinctively bonds with the first moving stimulus it perceives, whether it be its mother, or a person. Lorenz showed that this behavior of imprinting is what allows the goose to learn to recognize members of its own species, enabling them to be the object of subsequent behavior patterns such as mating. He developed a theory of instinctive behavior that saw behavior patterns as largely innate but triggered through environmental stimuli, for example the hawk/goose effect. He argued that animals have an inner drive to carry out instinctive behaviors, and that if they do not encounter the right stimulus they will eventually engage in the behavior with an inappropriate stimulus.

Lorenz's approach to ethology derived from a skepticism towards the studies of animal behavior done in laboratory settings. He considered that in order to understand the mechanisms of animal behavior, it was necessary to observe their full range of behaviors in their natural context. Lorenz did not carry out much traditional fieldwork but observed animals near his home. His method involved empathizing with animals, often using anthropomorphization to imagine their mental states. He believed that animals were capable of experiencing many of the same emotions as humans.

Tinbergen, Lorenz's friend with whom he conjointly received the Nobel prize, summarized Lorenz's major contribution to ethology as making behavior a topic of biological inquiry, considering behavior a part of an animal's evolutionary equipment. Tinbergen and Lorenz contributed to making Ethology a recognized sub-discipline within Biology and founded the first specialized journal of the field "Ethology" (originally "Zeitschift für Tierpsychologie")

Politics

Lorenz joined the Nazi Party in 1938 and accepted a university chair under the Nazi regime. In his application for party membership he wrote, "I'm able to say that my whole scientific work is devoted to the ideas of the National Socialists." His publications during that time led in later years to allegations that his scientific work had been contaminated by Nazi sympathies. His published writing during the Nazi period included support for Nazi ideas of "racial hygiene" couched in pseudoscientific metaphors.

In his autobiography, Lorenz wrote:

I was frightened—as I still am—by the thought that analogous genetical processes of deterioration may be at work with civilized humanity. Moved by this fear, I did a very ill-advised thing soon after the Germans had invaded Austria: I wrote about the dangers of domestication and, in order to be understood, I couched my writing in the worst of Nazi terminology. I do not want to extenuate this action. I did, indeed, believe that some good might come of the new rulers. The precedent narrow-minded catholic regime in Austria induced better and more intelligent men than I was to cherish this naive hope. Practically all my friends and teachers did so, including my own father who certainly was a kindly and humane man. None of us as much as suspected that the word "selection", when used by these rulers, meant murder. I regret those writings not so much for the undeniable discredit they reflect on my person as for their effect of hampering the future recognition of the dangers of domestication.

After the war, Lorenz denied having been a party member, until his membership application was made public; and he denied having known the extent of the genocide, despite his position as a psychologist in the Office of Racial Policy. He was also shown to have made anti-Semitic jokes on 'Jewish characteristics' in letters to his mentor Heinroth. In 2015, the University of Salzburg posthumously rescinded an honorary doctorate awarded to Lorenz in 1983, citing his party membership and his assertions in his application that he was "always a National Socialist", and that his work "stands to serve National Socialist thought". The university also accused him of using his work to spread "basic elements of the racist ideology of National Socialism".

During the final years of his life, Lorenz supported the fledgling Austrian Green Party and in 1984 became the figurehead of the Konrad Lorenz Volksbegehren, a grass-roots movement that was formed to prevent the building of a power plant at the Danube near Hainburg an der Donau and thus the destruction of the surrounding woodland.

Contributions and legacy

With Nikolaas Tinbergen (left), 1978

Lorenz has been called 'The father of ethology', by Niko Tinbergen. Perhaps Lorenz's most important contribution to ethology was his idea that behavior patterns can be studied as anatomical organs. This concept forms the foundation of ethological research. However, Richard Dawkins called Lorenz a "'good of the species' man", stating that the idea of group selection was "so deeply ingrained" in Lorenz's thinking that he "evidently did not realize that his statements contravened orthodox Darwinian theory."

Together with Nikolaas Tinbergen, Lorenz developed the idea of an innate releasing mechanism to explain instinctive behaviors (fixed action patterns). They experimented with "supernormal stimuli" such as giant eggs or dummy bird beaks which they found could release the fixed action patterns more powerfully than the natural objects for which the behaviors were adapted. Influenced by the ideas of William McDougall, Lorenz developed this into a "psychohydraulic" model of the motivation of behavior, which tended towards group selectionist ideas, which were influential in the 1960s. Another of his contributions to ethology is his work on imprinting. His influence on a younger generation of ethologists; and his popular works, were important in bringing ethology to the attention of the general public.

Lorenz claimed that there was widespread contempt for the descriptive sciences. He attributed this to the denial of perception as the source of all scientific knowledge: "a denial that has been elevated to the status of religion." He wrote that in comparative behavioral research, "it is necessary to describe various patterns of movement, record them, and above all, render them unmistakably recognizable."

There are three research institutions named after Lorenz in Austria: the Konrad Lorenz Institute for Evolution and Cognition Research (KLI) was housed in Lorenz' family mansion at Altenberg before moving to Klosterneuburg in 2013 Discover the KLI; the Konrad Lorenz Forschungsstelle (KLF) at his former field station in Grünau; and the Konrad Lorenz Institute of Ethology, an external research facility of the University of Veterinary Medicine Vienna.

Vision of the challenges facing humanity

With Nikolaas Tinbergen (right), 1978

Lorenz predicted the relationship between market economics and the threat of ecological catastrophe. In his 1973 book, Civilized Man's Eight Deadly Sins, Lorenz addresses the following paradox:

All the advantages that man has gained from his ever-deepening understanding of the natural world that surrounds him, his technological, chemical and medical progress, all of which should seem to alleviate human suffering... tends instead to favor humanity's destruction

Lorenz adopts an ecological model to attempt to grasp the mechanisms behind this contradiction. Thus "all species... are adapted to their environment... including not only inorganic components... but all the other living beings that inhabit the locality." p31.

Fundamental to Lorenz's theory of ecology is the function of negative feedback mechanisms, which, in hierarchical fashion, dampen impulses that occur beneath a certain threshold. The thresholds themselves are the product of the interaction of contrasting mechanisms. Thus pain and pleasure act as checks on each other:

To gain a desired prey, a dog or wolf will do things that, in other contexts, they would shy away from: run through thorn bushes, jump into cold water and expose themselves to risks which would normally frighten them. All these inhibitory mechanisms... act as a counterweight to the effects of learning mechanisms... The organism cannot allow itself to pay a price which is not worth paying. p53.

In nature, these mechanisms tend towards a 'stable state' among the living beings of an ecology:

A closer examination shows that these beings... not only do not damage each other, but often constitute a community of interests. It is obvious that the predator is strongly interested in the survival of that species, animal or vegetable, which constitutes its prey. ... It is not uncommon that the prey species derives specific benefits from its interaction with the predator species... pp31–33.

Lorenz states that humanity is the one species not bound by these mechanisms, being the only one that has defined its own environment:

[The pace of human ecology] is determined by the progress of man's technology (p35)... human ecology (economy) is governed by mechanisms of POSITIVE feedback, defined as a mechanism which tends to encourage behavior rather than to attenuate it (p43). Positive feedback always involves the danger of an 'avalanche' effect... One particular kind of positive feedback occurs when individuals OF THE SAME SPECIES enter into competition among themselves... For many animal species, environmental factors keep... intraspecies selection from [leading to] disaster... But there is no force which exercises this type of healthy regulatory effect on humanity's cultural development; unfortunately for itself, humanity has learned to overcome all those environmental forces which are external to itself p44.

Regarding aggression in human beings, Lorenz states:

Let us imagine that an absolutely unbiased investigator on another planet, perhaps on Mars, is examining human behavior on earth, with the aid of a telescope whose magnification is too small to enable him to discern individuals and follow their separate behavior, but large enough for him to observe occurrences such as migrations of peoples, wars, and similar great historical events. He would never gain the impression that human behavior was dictated by intelligence, still less by responsible morality. If we suppose our extraneous observer to be a being of pure reason, devoid of instincts himself and unaware of the way in which all instincts in general and aggression in particular can miscarry, he would be at a complete loss how to explain history at all. The ever-recurrent phenomena of history do not have reasonable causes. It is a mere commonplace to say that they are caused by what common parlance so aptly terms "human nature." Unreasoning and unreasonable human nature causes two nations to compete, though no economic necessity compels them to do so; it induces two political parties or religions with amazingly similar programs of salvation to fight each other bitterly, and it impels an Alexander or a Napoleon to sacrifice millions of lives in his attempt to unite the world under his scepter. We have been taught to regard some of the persons who have committed these and similar absurdities with respect, even as "great" men, we are wont to yield to the political wisdom of those in charge, and we are all so accustomed to these phenomena that most of us fail to realize how abjectly stupid and undesirable the historical mass behavior of humanity actually is.

Lorenz does not see human independence from natural ecological processes as necessarily bad. Indeed, he states that:

A completely new [ecology] which corresponds in every way to [humanity's] desires... could, theoretically, prove as durable as that which would have existed without his intervention (36).

However, the principle of competition, typical of Western societies, destroys any chance of this:

The competition between human beings destroys with cold and diabolic brutality... Under the pressure of this competitive fury we have not only forgotten what is useful to humanity as a whole, but even that which is good and advantageous to the individual. [...] One asks, which is more damaging to modern humanity: the thirst for money or consuming haste... in either case, fear plays a very important role: the fear of being overtaken by one's competitors, the fear of becoming poor, the fear of making wrong decisions or the fear of not being up to snuff... pp45–47.

In this book, Lorenz proposes that the best hope for mankind lies in our looking for mates based on the kindness of their hearts rather than good looks or wealth. He illustrates this with a Jewish story, explicitly described as such.

Lorenz was one of the early scientists who argue that human overpopulation could cause environmental degradation.

Philosophical speculations

In his 1973 book Behind the Mirror: A Search for a Natural History of Human Knowledge, Lorenz considers the old philosophical question of whether our senses correctly inform us about the world as it is, or provide us only with an illusion. His answer comes from evolutionary biology. Only traits that help us survive and reproduce are transmitted. If our senses gave us wrong information about our environment, we would soon be extinct. Therefore, we can be sure that our senses give us correct information, for otherwise we would not be here to be deceived.

Honours and awards

Works

Lorenz's best-known books are King Solomon's Ring and On Aggression, both written for a popular audience. His scientific work appeared mainly in journal articles, written in German; it became widely known to English-speaking scientists through its description in Tinbergen's 1951 book The Study of Instinct, though many of his papers were later published in English translation in the two volumes titled Studies in Animal and Human Behavior.

  • King Solomon's Ring (1949) (Er redete mit dem Vieh, den Vögeln und den Fischen, 1949)
  • Man Meets Dog (1950) (So kam der Mensch auf den Hund, 1950)
  • Evolution and Modification of Behaviour (1965)
  • On Aggression (1966) (Das sogenannte Böse. Zur Naturgeschichte der Aggression, 1963)
  • Studies in Animal and Human Behavior, Volume I (1970)
  • Studies in Animal and Human Behavior, Volume II (1971)
  • Motivation of Human and Animal Behavior: An Ethological View. With Paul Leyhausen (1973). New York: D. Van Nostrand Co. ISBN 0-442-24886-5
  • Behind the Mirror: A Search for a Natural History of Human Knowledge (1973) (Die Rückseite des Spiegels. Versuch einer Naturgeschichte menschlichen Erkennens, 1973)
  • Civilized Man's Eight Deadly Sins (1974) (Die acht Todsünden der zivilisierten Menschheit, 1973)
  • The Year of the Greylag Goose (1979) (Das Jahr der Graugans, 1979)
  • The Foundations of Ethology (1982)
  • The Waning of Humaneness (1987) (Der Abbau des Menschlichen, 1983)
  • Here I Am – Where Are You? – A Lifetime's Study of the Uncannily Human Behaviour of the Greylag Goose. (1988). Translated by Robert D. Martin from Hier bin ich – wo bist du?.
  • The Natural Science of the Human Species: An Introduction to Comparative Behavioral Research – The Russian Manuscript (1944–1948) (1995)


Neuroethology

From Wikipedia, the free encyclopedia
 
Echolocation in bats is one model system in neuroethology.

Neuroethology is the evolutionary and comparative approach to the study of animal behavior and its underlying mechanistic control by the nervous system. It is an interdisciplinary science that combines both neuroscience (study of the nervous system) and ethology (study of animal behavior in natural conditions). A central theme of neuroethology, which differentiates it from other branches of neuroscience, is its focus on behaviors that have been favored by natural selection (e.g., finding mates, navigation, locomotion, and predator avoidance) rather than on behaviors that are specific to a particular disease state or laboratory experiment.

Neuroethologists hope to uncover general principles of the nervous system from the study of animals with exaggerated or specialized behaviors. They endeavor to understand how the nervous system translates biologically relevant stimuli into natural behavior. For example, many bats are capable of echolocation which is used for prey capture and navigation. The auditory system of bats is often cited as an example for how acoustic properties of sounds can be converted into a sensory map of behaviorally relevant features of sounds.

Philosophy

Neuroethology is an integrative approach to the study of animal behavior that draws upon several disciplines. Its approach stems from the theory that animals' nervous systems have evolved to address problems of sensing and acting in certain environmental niches and that their nervous systems are best understood in the context of the problems they have evolved to solve. In accordance with Krogh's principle, neuroethologists often study animals that are "specialists" in the behavior the researcher wishes to study e.g. honeybees and social behavior, bat echolocation, owl sound localization, etc.

The scope of neuroethological inquiry might be summarized by Jörg-Peter Ewert, a pioneer of neuroethology, when he considers the types of questions central to neuroethology in his 1980 introductory text to the field:

  1. How are stimuli detected by an organism?
  2. How are environmental stimuli in the external world represented in the nervous system?
  3. How is information about a stimulus acquired, stored and recalled by the nervous system?
  4. How is a behavioral pattern encoded by neural networks?
  5. How is behavior coordinated and controlled by the nervous system?
  6. How can the ontogenetic development of behavior be related to neural mechanisms?

Often central to addressing questions in neuroethology are comparative methodologies, drawing upon knowledge about related organisms' nervous systems, anatomies, life histories, behaviors and environmental niches. While it is not unusual for many types of neurobiology experiments to give rise to behavioral questions, many neuroethologists often begin their research programs by observing a species' behavior in its natural environment. Other approaches to understanding nervous systems include the systems identification approach, popular in engineering. The idea is to stimulate the system using a non-natural stimulus with certain properties. The system's response to the stimulus may be used to analyze the operation of the system. Such an approach is useful for linear systems, but the nervous system is notoriously nonlinear, and neuroethologists argue that such an approach is limited. This argument is supported by experiments in the auditory system, which show that neural responses to complex sounds, like social calls, can not be predicted by the knowledge gained from studying the responses due to pure tones (one of the non-natural stimuli favored by auditory neurophysiologists). This is because of the non-linearity of the system.

Modern neuroethology is largely influenced by the research techniques used. Neural approaches are necessarily very diverse, as is evident through the variety of questions asked, measuring techniques used, relationships explored, and model systems employed. Techniques utilized since 1984 include the use of intracellular dyes, which make maps of identified neurons possible, and the use of brain slices, which bring vertebrate brains into better observation through intracellular electrodes (Hoyle 1984). Currently, other fields toward which neuroethology may be headed include computational neuroscience, molecular genetics, neuroendocrinology and epigenetics. The existing field of neural modeling may also expand into neuroethological terrain, due to its practical uses in robotics. In all this, neuroethologists must use the right level of simplicity to effectively guide research towards accomplishing the goals of neuroethology.

Critics of neuroethology might consider it a branch of neuroscience concerned with 'animal trivia'. Though neuroethological subjects tend not to be traditional neurobiological model systems (i.e. Drosophila, C. elegans, or Danio rerio), neuroethological approaches emphasizing comparative methods have uncovered many concepts central to neuroscience as a whole, such as lateral inhibition, coincidence detection, and sensory maps. The discipline of neuroethology has also discovered and explained the only vertebrate behavior for which the entire neural circuit has been described: the electric fish jamming avoidance response. Beyond its conceptual contributions, neuroethology makes indirect contributions to advancing human health. By understanding simpler nervous systems, many clinicians have used concepts uncovered by neuroethology and other branches of neuroscience to develop treatments for devastating human diseases.

History

Neuroethology owes part of its existence to the establishment of ethology as a unique discipline within zoology. Although animal behavior had been studied since the time of Aristotle (384–342 BC), it was not until the early twentieth century that ethology finally became distinguished from natural science (a strictly descriptive field) and ecology. The main catalysts behind this new distinction were the research and writings of Konrad Lorenz and Niko Tinbergen.

Konrad Lorenz was born in Austria in 1903, and is widely known for his contribution of the theory of fixed action patterns (FAPs): endogenous, instinctive behaviors involving a complex sequence of movements that are triggered ("released") by a certain kind of stimulus. This sequence always proceeds to completion, even if the original stimulus is removed. It is also species-specific and performed by nearly all members. Lorenz constructed his famous "hydraulic model" to help illustrate this concept, as well as the concept of action specific energy, or drives.

Niko Tinbergen was born in the Netherlands in 1907 and worked closely with Lorenz in the development of the FAP theory; their studies focused on the egg retrieval response of nesting geese. Tinbergen performed extensive research on the releasing mechanisms of particular FAPs, and used the bill-pecking behavior of baby herring gulls as his model system. This led to the concept of the supernormal stimulus. Tinbergen is also well known for his four questions that he believed ethologists should be asking about any given animal behavior; among these is that of the mechanism of the behavior, on a physiological, neural and molecular level, and this question can be thought of in many regards as the keystone question in neuroethology. Tinbergen also emphasized the need for ethologists and neurophysiologists to work together in their studies, a unity that has become a reality in the field of neuroethology.

Unlike behaviorism, which studies animals' reactions to non-natural stimuli in artificial, laboratory conditions, ethology sought to categorize and analyze the natural behaviors of animals in a field setting. Similarly, neuroethology asks questions about the neural bases of naturally occurring behaviors, and seeks to mimic the natural context as much as possible in the laboratory.

Although the development of ethology as a distinct discipline was crucial to the advent of neuroethology, equally important was the development of a more comprehensive understanding of neuroscience. Contributors to this new understanding were the Spanish Neuroanatomist, Ramon y Cajal (born in 1852), and physiologists Charles Sherrington, Edgar Adrian, Alan Hodgkin, and Andrew Huxley. Charles Sherrington, who was born in Great Britain in 1857, is famous for his work on the nerve synapse as the site of transmission of nerve impulses, and for his work on reflexes in the spinal cord. His research also led him to hypothesize that every muscular activation is coupled to an inhibition of the opposing muscle. He was awarded a Nobel Prize for his work in 1932 along with Lord Edgar Adrian who made the first physiological recordings of neural activity from single nerve fibers.

Alan Hodgkin and Andrew Huxley (born 1914 and 1917, respectively, in Great Britain), are known for their collaborative effort to understand the production of action potentials in the giant axons of squid. The pair also proposed the existence of ion channels to facilitate action potential initiation, and were awarded the Nobel Prize in 1963 for their efforts.

As a result of this pioneering research, many scientists then sought to connect the physiological aspects of the nervous and sensory systems to specific behaviors. These scientists – Karl von Frisch, Erich von Holst, and Theodore Bullock – are frequently referred to as the "fathers" of neuroethology. Neuroethology did not really come into its own, though, until the 1970s and 1980s, when new, sophisticated experimental methods allowed researchers such as Masakazu Konishi, Walter Heiligenberg, Jörg-Peter Ewert, and others to study the neural circuits underlying verifiable behavior.

Modern neuroethology

The International Society for Neuroethology represents the present discipline of neuroethology, which was founded on the occasion of the NATO-Advanced Study Institute "Advances in Vertebrate Neuroethology" (August 13–24, 1981) organized by J.-P. Ewert, D.J. Ingle and R.R. Capranica, held at the University of Kassel in Hofgeismar, Germany (cf. report Trends in Neurosci. 5:141-143,1982). Its first president was Theodore H. Bullock. The society has met every three years since its first meeting in Tokyo in 1986.

Its membership draws from many research programs around the world; many of its members are students and faculty members from medical schools and neurobiology departments from various universities. Modern advances in neurophysiology techniques have enabled more exacting approaches in an ever-increasing number of animal systems, as size limitations are being dramatically overcome. Survey of the most recent (2007) congress of the ISN meeting symposia topics gives some idea of the field's breadth:

  • Comparative aspects of spatial memory (rodents, birds, humans, bats)
  • Influences of higher processing centers in active sensing (primates, owls, electric fish, rodents, frogs)
  • Animal signaling plasticity over many time scales (electric fish, frogs, birds)
  • Song production and learning in passerine birds
  • Primate sociality
  • Optimal function of sensory systems (flies, moths, frogs, fish)
  • Neuronal complexity in behavior (insects, computational)
  • Contributions of genes to behavior (Drosophila, honeybees, zebrafish)
  • Eye and head movement (crustaceans, humans, robots)
  • Hormonal actions in brain and behavior (rodents, primates, fish, frogs, and birds)
  • Cognition in insects (honeybee)

Application to technology

Neuroethology can help create advancements in technology through an advanced understanding of animal behavior. Model systems were generalized from the study of simple and related animals to humans. For example, the neuronal cortical space map discovered in bats, a specialized champion of hearing and navigating, elucidated the concept of a computational space map. In addition, the discovery of the space map in the barn owl led to the first neuronal example of the Jeffress model. This understanding is translatable to understanding spatial localization in humans, a mammalian relative of the bat. Today, knowledge learned from neuroethology are being applied in new technologies. For example, Randall Beer and his colleagues used algorithms learned from insect walking behavior to create robots designed to walk on uneven surfaces (Beer et al.). Neuroethology and technology contribute to one another bidirectionally.

Neuroethologists seek to understand the neural basis of a behavior as it would occur in an animal's natural environment but the techniques for neurophysiological analysis are lab-based, and cannot be performed in the field setting. This dichotomy between field and lab studies poses a challenge for neuroethology. From the neurophysiology perspective, experiments must be designed for controls and objective rigor, which contrasts with the ethology perspective – that the experiment be applicable to the animal's natural condition, which is uncontrolled, or subject to the dynamics of the environment. An early example of this is when Walter Rudolf Hess developed focal brain stimulation technique to examine a cat's brain controls of vegetative functions in addition to other behaviors. Even though this was a breakthrough in technological abilities and technique, it was not used by many neuroethologists originally because it compromised a cat's natural state, and, therefore, in their minds, devalued the experiments' relevance to real situations.

When intellectual obstacles like this were overcome, it led to a golden age of neuroethology, by focusing on simple and robust forms of behavior, and by applying modern neurobiological methods to explore the entire chain of sensory and neural mechanisms underlying these behaviors (Zupanc 2004). New technology allows neuroethologists to attach electrodes to even very sensitive parts of an animal such as its brain while it interacts with its environment. The founders of neuroethology ushered this understanding and incorporated technology and creative experimental design. Since then even indirect technological advancements such as battery-powered and waterproofed instruments have allowed neuroethologists to mimic natural conditions in the lab while they study behaviors objectively. In addition, the electronics required for amplifying neural signals and for transmitting them over a certain distance have enabled neuroscientists to record from behaving animals performing activities in naturalistic environments. Emerging technologies can complement neuroethology, augmenting the feasibility of this valuable perspective of natural neurophysiology.

Another challenge, and perhaps part of the beauty of neuroethology, is experimental design. The value of neuroethological criteria speak to the reliability of these experiments, because these discoveries represent behavior in the environments in which they evolved. Neuroethologists foresee future advancements through using new technologies and techniques, such as computational neuroscience, neuroendocrinology, and molecular genetics that mimic natural environments.

Case studies

Jamming avoidance response

In 1963, Akira Watanabe and Kimihisa Takeda discovered the behavior of the jamming avoidance response in the knifefish Eigenmannia sp. In collaboration with T.H. Bullock and colleagues, the behavior was further developed. Finally, the work of W. Heiligenberg expanded it into a full neuroethology study by examining the series of neural connections that led to the behavior. Eigenmannia is a weakly electric fish that can generate electric discharges through electrocytes in its tail. Furthermore, it has the ability to electrolocate by analyzing the perturbations in its electric field. However, when the frequency of a neighboring fish's current is very close (less than 20 Hz difference) to that of its own, the fish will avoid having their signals interfere through a behavior known as Jamming Avoidance Response. If the neighbor's frequency is higher than the fish's discharge frequency, the fish will lower its frequency, and vice versa. The sign of the frequency difference is determined by analyzing the "beat" pattern of the incoming interference which consists of the combination of the two fish's discharge patterns.

Neuroethologists performed several experiments under Eigenmannia's natural conditions to study how it determined the sign of the frequency difference. They manipulated the fish's discharge by injecting it with curare which prevented its natural electric organ from discharging. Then, an electrode was placed in its mouth and another was placed at the tip of its tail. Likewise, the neighboring fish's electric field was mimicked using another set of electrodes. This experiment allowed neuroethologists to manipulate different discharge frequencies and observe the fish's behavior. From the results, they were able to conclude that the electric field frequency, rather than an internal frequency measure, was used as a reference. This experiment is significant in that not only does it reveal a crucial neural mechanism underlying the behavior but also demonstrates the value neuroethologists place on studying animals in their natural habitats.

Feature analysis in toad vision

The recognition of prey and predators in the toad was first studied in depth by Jörg-Peter Ewert (Ewert 1974; see also 2004). He began by observing the natural prey-catching behavior of the common toad (Bufo bufo) and concluded that the animal followed a sequence that consisted of stalking, binocular fixation, snapping, swallowing and mouth-wiping. However, initially, the toad's actions were dependent on specific features of the sensory stimulus: whether it demonstrated worm or anti-worm configurations. It was observed that the worm configuration, which signaled prey, was initiated by movement along the object's long axis, whereas anti-worm configuration, which signaled predator, was due to movement along the short axis. (Zupanc 2004).

Ewert and coworkers adopted a variety of methods to study the predator versus prey behavior response. They conducted recording experiments where they inserted electrodes into the brain, while the toad was presented with worm or anti-worm stimuli. This technique was repeated at different levels of the visual system and also allowed feature detectors to be identified. In focus was the discovery of prey-selective neurons in the optic tectum, whose axons could be traced towards the snapping pattern generating cells in the hypoglossal nucleus. The discharge patterns of prey-selective tectal neurons in response to prey objects – in freely moving toads – "predicted" prey-catching reactions such as snapping. Another approach, called stimulation experiment, was carried out in freely moving toads. Focal electrical stimuli were applied to different regions of the brain, and the toad's response was observed. When the thalamic-pretectal region was stimulated, the toad exhibited escape responses, but when the tectum was stimulated in an area close to prey-selective neurons, the toad engaged in prey catching behavior (Carew 2000). Furthermore, neuroanatomical experiments were carried out where the toad's thalamic-pretectal/tectal connection was lesioned and the resulting deficit noted: the prey-selective properties were abolished both in the responses of prey-selective neurons and in the prey catching behavior. These and other experiments suggest that prey selectivity results from pretecto-tectal influences.

Ewert and coworkers showed in toads that there are stimulus-response mediating pathways that translate perception (of visual sign stimuli) into action (adequate behavioral responses). In addition there are modulatory loops that initiate, modify or specify this mediation (Ewert 2004). Regarding the latter, for example, the telencephalic caudal ventral striatum is involved in a loop gating the stimulus-response mediation in a manner of directed attention. The telencephalic ventral medial pallium („primordium hippocampi"), however, is involved in loops that either modify prey-selection due to associative learning or specify prey-selection due to non-associative learning, respectively.

Computational neuroethology

Computational neuroethology (CN or CNE) is concerned with the computer modelling of the neural mechanisms underlying animal behaviors. Together with the term "artificial ethology," the term "computational neuroethology" was first published in literature by Achacoso and Yamamoto in the Spring of 1990, based on their pioneering work on the connectome of C. elegans in 1989, with further publications in 1992. Computational neuroethology was argued for in depth later in 1990 by Randall Beer and by Dave Cliff both of whom acknowledged the strong influence of Michael Arbib's Rana Computatrix computational model of neural mechanisms for visual guidance in frogs and toads.

CNE systems work within a closed-loop environment; that is, they perceive their (perhaps artificial) environment directly, rather than through human input, as is typical in AI systems. For example, Barlow et al. developed a time-dependent model for the retina of the horseshoe crab Limulus polyphemus on a Connection Machine (Model CM-2). Instead of feeding the model retina with idealized input signals, they exposed the simulation to digitized video sequences made underwater, and compared its response with those of real animals.

Model systems

 

Animal language

From Wikipedia, the free encyclopedia
 

Animal languages are forms of non-human animal communication that show similarities to human language. Animals communicate by using a variety of signs such as sounds or movements. Such signing may be considered complex enough to be called a form of language if the inventory of signs is large, the signs are relatively arbitrary, and the animals seem to produce them with a degree of volition (as opposed to relatively automatic conditioned behaviors or unconditioned instincts, usually including facial expressions). In experimental tests, animal communication may also be evidenced through the use of lexigrams (as used by chimpanzees and bonobos).

Many researchers argue that animal communication lacks a key aspect of human language, that is, the creation of new patterns of signs under varied circumstances. (In contrast, for example, humans routinely produce entirely new combinations of words.) Some researchers, including the linguist Charles Hockett, argue that human language and animal communication differ so much that the underlying principles are unrelated. Accordingly, linguist Thomas A. Sebeok has proposed to not use the term "language" for animal sign systems.[2] Marc Hauser, Noam Chomsky, and W. Tecumseh Fitch assert an evolutionary continuum exists between the communication methods of animal and human language.

Aspects of human language

Human and chimp, in this case Claudine André with a bonobo.

The following properties of human language have been argued to separate it from animal communication:

  • Arbitrariness: there is usually no rational relationship between a sound or sign and its meaning. For example, there is nothing intrinsically house-like about the word "house".
  • Discreteness: language is composed of small, repeatable parts (discrete units) that are used in combination to create meaning.
  • Displacement: languages can be used to communicate ideas about things that are not in the immediate vicinity either spatially or temporally.
  • Duality of patterning: the smallest meaningful units (words, morphemes) consist of sequences of units without meaning. This is also referred to as double articulation.
  • Productivity: users can understand and create an indefinitely large number of utterances.
  • Semanticity: specific signals have specific meanings.

Research with apes, like that of Francine Patterson with Koko (gorilla) or Allen and Beatrix Gardner with Washoe (chimpanzee), suggested that apes are capable of using language that meets some of these requirements such as arbitrariness, discreteness, and productivity.

In the wild, chimpanzees have been seen "talking" to each other when warning about approaching danger. For example, if one chimpanzee sees a snake, he makes a low, rumbling noise, signaling for all the other chimps to climb into nearby trees. In this case, the chimpanzees' communication does not indicate displacement, as it is entirely contained to an observable event.

Arbitrariness has been noted in meerkat calls; bee dances demonstrate elements of spatial displacement; and cultural transmission has possibly occurred between the celebrated bonobos Kanzi and Panbanisha.

Human language may not be completely "arbitrary." Research has shown that almost all humans naturally demonstrate limited crossmodal perception (e.g. synesthesia) and multisensory integration, as illustrated by the Kiki and Booba study. Other recent research has tried to explain how the structure of human language emerged, comparing two different aspects of hierarchical structure present in animal communication and proposing that human language arose out of these two separate systems.

Claims that animals have language skills akin to humans however, are extremely controversial. As Steven Pinker illustrates in his book The Language Instinct, claims that chimpanzees can acquire language are exaggerated and rest on very limited or specious data.

The American linguist Charles Hockett theorized that there are sixteen features of human language that distinguished human communication from that of animals. He called these the design features of language. The features mentioned below have so far been found in all spoken human languages and at least one is missing from all other animal communication systems.

  • Vocal-auditory channel: sounds emitted from the mouth and perceived by the auditory system. This applies to many animal communication systems, but there are many exceptions. Ex. An alternative to vocal-auditory communication is visual communication. An example is cobras extending the ribs behind their heads to send the message of intimidation or of feeling threatened. In humans, sign languages provide many examples of fully formed languages that use a visual channel.
  • Broadcast transmission and directional reception: this requires that the recipient can tell the direction that the signal comes from and thus the originator of the signal.
  • Rapid fading (transitory nature): Signal lasts a short time. This is true of all systems involving sound. It does not take into account audio recording technology and is also not true for written language. It tends not to apply to animal signals involving chemicals and smells which often fade slowly. For example, a skunk's smell, produced in its glands, lingers to deter a predator from attacking.
  • Interchangeability: All utterances that are understood can be produced. This is different from some communication systems where, for example, males produce one set of behaviours and females another and they are unable to interchange these messages so that males use the female signal and vice versa. For example, Heliothine moths have differentiated communication: females are able to send a chemical to indicate preparedness to mate, while males cannot send the chemical.
  • Total feedback: The sender of a message is aware of the message being sent.
  • Specialization: The signal produced is intended for communication and is not due to another behavior. For example, dog panting is a natural reaction to being overheated, but is not produced to specifically relay a particular message.
  • Semanticity: There is some fixed relationship between a signal and a meaning.

Primate: studied examples

Humans are able to distinguish real words from fake words based on the phonological order of the word itself. In a 2013 study, baboons have been shown to have this skill, as well. The discovery has led researchers to believe that reading is not as advanced a skill as previously believed, but instead based on the ability to recognize and distinguish letters from one another. The experimental setup consisted of six young adult baboons, and results were measured by allowing the animals to use a touch screen and selecting whether or not the displayed word was indeed a real word, or a nonword such as "dran" or "telk." The study lasted for six weeks, with approximately 50,000 tests completed in that time. The experimenters explain the use of bigrams, which are combinations of two (usually different) letters. They tell us that the bigrams used in nonwords are rare, while the bigrams used in real words are more common. Further studies will attempt to teach baboons how to use an artificial alphabet.

In a 2016 study, a team of biologists from several universities concluded that macaques possess vocal tracts physically capable of speech, "but lack a speech-ready brain to control it".

Non-primates: studied examples

Among the most studied examples of animal languages are:

Birds

  • Bird songs: Songbirds can be very articulate. Grey parrots are famous for their ability to mimic human language, and at least one specimen, Alex, appeared able to answer a number of simple questions about objects he was presented with. Parrots, hummingbirds and songbirds – display vocal learning patterns.

Insects

  • Bee dance: Used to communicate direction and distance of food source in many species of bees.

Mammals

  • African forest elephants: Cornell University's Elephant Listening Project began in 1999 when Katy Payne began studying the calls of African forest elephants in Dzanga National Park in the Central African Republic. Andrea Turkalo has continued Payne's work in Dzanga National Park observing elephant communication. For nearly 20 years, Turkalo has spent the majority of her time using a spectrogram to record the noises that the elephants make. After extensive observation and research, she has been able to recognize elephants by their voices. Researchers hope to translate these voices into an elephant dictionary, but that will likely not occur for many years. Because elephant calls are often made at very low frequencies, this spectrogram is able to detect lower frequencies that human ears are unable to hear, allowing Turkalo to get a better idea of what she perceives the elephants to be saying. Cornell's research on African forest elephants has challenged the idea that humans are considerably better at using language and that animals only have a small repertoire of information that they can convey to others. As Turkalo explained on 60 Minutes' "The Secret Language of Elephants," "Many of their calls are in some ways similar to human speech."
  • Mustached bats: Since these animals spend most of their lives in the dark, they rely heavily on their auditory system to communicate. This acoustic communication includes echolocation or using calls to locate each other in the darkness. Studies have shown that mustached bats use a wide variety of calls to communicate with one another. These calls include 33 different sounds, or "syllables," that the bats then either use alone or combine in various ways to form "composite" syllables.
  • Prairie dogs: Dr. Con Slobodchikoff studied prairie dog communication and discovered:
    • different alarm calls for different species of predators;
    • different escape behaviors for different species of predators;
    • transmission of semantic information, in that playbacks of alarm calls in the absence of predators lead to escape behaviors that are appropriate to the type of predator which elicited the alarm calls;
    • alarm calls containing descriptive information about the general size, color, and speed of travel of the predator.

Aquatic mammals

  • Bottlenose dolphins: Dolphins can hear one another up to 6 miles apart underwater. In one National Geographic article, the success of a mother dolphin communicating with her baby using a telephone was outlined. Researchers noted that it appeared that both dolphins knew who they were speaking with and what they were speaking about. Not only do dolphins communicate via nonverbal cues, but they also seem to chatter and respond to other dolphin's vocalizations.
Spectrogram of humpback whale vocalizations. Detail is shown for the first 24 seconds of the 37 second recording humpback whale "song". The ethereal whale "songs" and echolocation "clicks" are visible as horizontal striations and vertical sweeps respectively.
  • Whales: Two groups of whales, the humpback whale and a subspecies of blue whale found in the Indian Ocean, are known to produce repetitious sounds at varying frequencies known as whale song. Male humpback whales perform these vocalizations only during the mating season, and so it is surmised the purpose of songs is to aid sexual selection. Humpbacks also make a sound called a feeding call, five to ten seconds in length of near constant frequency. Humpbacks generally feed cooperatively by gathering in groups, swimming underneath shoals of fish and all lunging up vertically through the fish and out of the water together. Prior to these lunges, whales make their feeding call. The exact purpose of the call is not known, but research suggests that fish react to it. When the sound was played back to them, a group of herring responded to the sound by moving away from the call, even though no whale was present.
  • Sea lions: Beginning in 1971 and continuing until present day, Dr. Ronald J. Schusterman and his research associates have studied sea lions' cognitive ability. They have discovered that sea lions are able to recognize relationships between stimuli based on similar functions or connections made with their peers, rather than only the stimuli's common features. This is called "equivalence classification". This ability to recognize equivalence may be a precursor to language. Research is currently being conducted at the Pinniped Cognition & Sensory Systems Laboratory to determine how sea lions form these equivalence relationships. Sea lions have also been proven to be able to understand simple syntax and commands when taught an artificial sign language similar to the one used with primates. The sea lions studied were able to learn and use a number of syntactic relations between the signs they were taught, such as how the signs should be arranged in relation to each other. However, the sea lions rarely used the signs semantically or logically. In the wild it's thought that sea lions use the reasoning skills associated with equivalence classification in order to make important decisions that can affect their rate of survival (e.g. recognizing friends and family or avoiding enemies and predators). Sea lions use the following to display their language:
    • Sea lions use their bodies in various postural positions to display communication.
    • Sea lion's vocal cords limit their ability to convey sounds to a range of barks, chirps, clicks, moans, growls and squeaks.
    • There has yet to be an experiment which proves for certain that sea lions use echolocation as a means of communication.

The effects of learning on auditory signaling in these animals is of special interest. Several investigators have pointed out that some marine mammals appear to have an extraordinary capacity to alter both the contextual and structural features of their vocalizations as a result of experience. Janik and Slater (2000) have stated that learning can modify the emission of vocalizations in one of two ways: (1) by influencing the context in which a particular signal is used and/or (2) by altering the acoustic structure of the call itself. Male California sea lions can learn to inhibit their barking in the presence of any male dominant to them, but vocalize normally when dominant males are absent. Recent work on gray seals show different call types can be selectively conditioned and placed under biased control of different cues (Schusterman, in press) and the use of food reinforcement can also modify vocal emissions. "Hoover", a captive male harbor seal demonstrated a convincing case of vocal mimicry. However similar observations have not been reported since. Still shows under the right circumstances pinnipeds may use auditory experience, in addition to environmental consequences such as food reinforcement and social feedback to modify their vocal emissions.

In a 1992 study, Robert Gisiner and Ronald J. Schusterman conducted experiments in which they attempted to teach Rocky, a female California sea lion, syntax. Rocky was taught signed words, then she was asked to perform various tasks dependent on word order after viewing a signed instruction. It was found that Rocky was able to determine relations between signs and words, and form a basic form of syntax. A 1993 study by Ronald J Schusterman and David Kastak found that the California sea lion was capable of understanding abstract concepts such as symmetry, sameness and transitivity. This provides a strong backing to the theory that equivalence relations can form without language.

The distinctive sound of sea lions is produced both above and below water. To mark territory, sea lions "bark", with non-alpha males making more noise than alphas. Although females also bark, they do so less frequently and most often in connection with birthing pups or caring for their young. Females produce a highly directional bawling vocalization, the pup attraction call, which helps mother and pup locate one another. As noted in Animal Behavior, their amphibious lifestyle has made them need acoustic communication for social organization while on land.

Sea lions can hear frequencies as low as 100 Hz and as high as 40,000 Hz and vocalize between the ranges of 100 to 10,000 Hz.

Mollusks

  • Caribbean reef squid have been shown to communicate using a variety of color, shape, and texture changes. Squid are capable of rapid changes in skin color and pattern through nervous control of chromatophores. In addition to camouflage and appearing larger in the face of a threat, squids use color, patterns, and flashing to communicate with one another in various courtship rituals. Caribbean reef squid can send one message via color patterns to a squid on their right, while they send another message to a squid on their left.

Comparison of the terms "animal language" and "animal communication"

It is worth distinguishing "animal language" from "animal communication", although there is some comparative interchange in certain cases (e.g. Cheney & Seyfarth's vervet monkey call studies). Thus "animal language" typically does not include bee dancing, bird song, whale song, dolphin signature whistles, prairie dogs, nor the communicative systems found in most social mammals. The features of language as listed above are a dated formulation by Hockett in 1960. Through this formulation Hockett made one of the earliest attempts to break down features of human language for the purpose of applying Darwinian gradualism. Although an influence on early animal language efforts (see below), is today not considered the key architecture at the core of "animal language" research.

"Clever Hans", an Orlov Trotter horse that was claimed to have been able to perform arithmetic and other intellectual tasks.

Animal Language results are controversial for several reasons. (For a related controversy, see also Clever Hans.) In the 1970s John Lilly was attempting to "break the code": to fully communicate ideas and concepts with wild populations of dolphins so that we could "speak" to them, and share our cultures, histories, and more. This effort failed. Early chimpanzee work was with chimpanzee infants raised as if they were human; a test of the nature vs. nurture hypothesis. Chimpanzees have a laryngeal structure very different from that of humans, and it has been suggested that chimpanzees are not capable of voluntary control of their breathing, although better studies are needed to accurately confirm this. This combination is thought to make it very difficult for the chimpanzees to reproduce the vocal intonations required for human language. Researchers eventually moved towards a gestural (sign language) modality, as well as "keyboard" devices laden with buttons adorned with symbols (known as "lexigrams") that the animals could press to produce artificial language. Other chimpanzees learned by observing human subjects performing the task. This latter group of researchers studying chimpanzee communication through symbol recognition (keyboard) as well as through the use of sign language (gestural), are on the forefront of communicative breakthroughs in the study of animal language, and they are familiar with their subjects on a first name basis: Sarah, Lana, Kanzi, Koko, Sherman, Austin and Chantek.

Perhaps the best known critic of "Animal Language" is Herbert Terrace. Terrace's 1979 criticism using his own research with the chimpanzee Nim Chimpsky was scathing and basically spelled the end of animal language research in that era, most of which emphasized the production of language by animals. In short, he accused researchers of over-interpreting their results, especially as it is rarely parsimonious to ascribe true intentional "language production" when other simpler explanations for the behaviors (gestural hand signs) could be put forth. Also, his animals failed to show generalization of the concept of reference between the modalities of comprehension and production; this generalization is one of many fundamental ones that are trivial for human language use. The simpler explanation according to Terrace was that the animals had learned a sophisticated series of context-based behavioral strategies to obtain either primary (food) or social reinforcement, behaviors that could be over-interpreted as language use.

In 1984 during this anti-Animal Language backlash, Louis Herman published an account of artificial language in the bottlenosed dolphin in the journal Cognition. A major difference between Herman's work and previous research was his emphasis on a method of studying language comprehension only (rather than language comprehension and production by the animal(s)), which enabled rigorous controls and statistical tests, largely because he was limiting his researchers to evaluating the animals' physical behaviors (in response to sentences) with blinded observers, rather than attempting to interpret possible language utterances or productions. The dolphins' names here were Akeakamai and Phoenix. Irene Pepperberg used the vocal modality for language production and comprehension in a grey parrot named Alex in the verbal mode, and Sue Savage-Rumbaugh continues to study bonobos such as Kanzi and Panbanisha. R. Schusterman duplicated many of the dolphin results in his California sea lions ("Rocky"), and came from a more behaviorist tradition than Herman's cognitive approach. Schusterman's emphasis is on the importance on a learning structure known as "equivalence classes."

However, overall, there has not been any meaningful dialog between the linguistics and animal language spheres, despite capturing the public's imagination in the popular press. Also, the growing field of language evolution is another source of future interchange between these disciplines. Most primate researchers tend to show a bias toward a shared pre-linguistic ability between humans and chimpanzees, dating back to a common ancestor, while dolphin and parrot researchers stress the general cognitive principles underlying these abilities. More recent related controversies regarding animal abilities include the closely linked areas of Theory of mind, Imitation (e.g. Nehaniv & Dautenhahn, 2002), Animal Culture (e.g. Rendell & Whitehead, 2001), and Language Evolution (e.g. Christiansen & Kirby, 2003).

There has been a recent emergence in animal language research which has contested the idea that animal communication is less sophisticated than human communication. Denise Herzing has done research on dolphins in the Bahamas whereby she created a two-way conversation via a submerged keyboard. The keyboard allows divers to communicate with wild dolphins. By using sounds and symbols on each key the dolphins could either press the key with their nose or mimic the whistling sound emitted in order to ask humans for a specific prop. This ongoing experiment has shown that in non-linguistic creatures brilliant and rapid thinking does occur despite our previous conceptions of animal communication. Further research done with Kanzi using lexigrams has strengthened the idea that animal communication is much more complex then we once thought.

Introduction to entropy

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Introduct...