| Ethology
Ethology is the scientific study of animal behaviour considered
as a branch of zoology. A scientist who practises ethology is called
an ethologist.
Origins of the name
The term “ethology” derives from the Greek language,
as ethos (????) is the Greek word for "custom". Other
words that derive from the Greek word ethos are: ethics and ethical.
The term was first popularised 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 System
of Logic. 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 associationistic psychology.
This use of the word was never adopted, however.
Differences and similarities with comparative psychology
Ethology can be contrasted with comparative psychology, which also
studies animal behaviour, but construes its study as a branch of
psychology. Thus where comparative psychology sees the study of
animal behaviour in the context of what is known about human psychology,
ethology sees the study of animal behaviour in the context of what
is known about animal anatomy and physiology. Furthermore, early
comparative psychologists concentrated on the study of learning,
and thus tended to look at behaviour in artificial situations, whereas
early ethologists concentrated on behaviour in natural situations,
tending to describe it as instinctive. 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 comparative psychology
developed most strongly in North America, while ethology was stronger
in Europe, and this led to different emphases as well as somewhat
different philosophical underpinnings in the two disciplines. A
practical difference is that comparative psychologists concentrated
on gaining extensive knowledge of the behaviour of very few species,
while ethologists were more interested in gaining knowledge of behaviour
in a wide range of species, not least in order to be able to make
principled comparisons across taxonomic groups. Ethologists have
made much more use of a truly comparative method than comparative
psychologists ever have.
Darwinism and the beginnings of ethology
Because ethology is understood as a branch of biology, ethologists
have been particularly concerned with the evolution of behaviour
and the understanding of behaviour 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 animals and
men influenced many ethologists. However, he pursued his interest
in behaviour by encouraging his protégé George Romanes,
who investigated animal learning and intelligence using an anthropormorphic
method that did not gain scientific support. The early ethologists,
such as Oskar Heinroth and Julian Huxley instead concentrated on
behaviours that can be called instinctive, or natural, in that they
occur in all members of a species under specified circumstances.
Their first step in studying the behaviour of a new species was
to construct an ethogram, a description of the main types of natural
behaviour with their frequencies of occurrence. This approach provided
an objective, cumulative base of data about behaviour, which subsequent
researchers could check and build on, and as a way of building a
science of behaviour, it proved much more fruitful.
The Fixed Action Pattern and animal communication
An important step, associated with the name of Konrad Lorenz though
probably due more to his teacher, Heinroth, was the identification
of fixed action patterns (FAPs). Lorenz popularized FAPs as instinctive
responses that would occur reliably in the presence of identifiable
stimuli (called sign stimuli or releasing stimuli). These FAPs could
then be compared across species, and the similarities and differences
between behaviour compared with the similarities and differences
in morphology on which taxonomy was based. An important and much
quoted study of the Anatidae (ducks and geese) by Heinroth used
this technique. The ethologists noted that the stimuli that released
FAPs were commonly features of the appearance or behaviour of other
members of their own species, and they were able to show how important
forms of animal communication could be mediated by a few simple
FAPs. The most sophisticated investigation of this kind was the
study by Karl von Frisch of the so-called “dance language”
underlying bee communication. Lorenz developed an interesting theory
of the evolution of animal communication based on his observations
of the nature of fixed action patterns and the circumstances in
which animals emit them.
Imprinting
A second important finding of Lorenz concerned the early learning
of young nidifugous birds, a process he called imprinting. 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, and he discovered that this following response could be
transferred to an arbitrary stimulus if the eggs were incubated
artificially and the stimulus was presented during a critical period
(now called a sensitive period) that covered the few days after
hatching. The concept of imprinting has been widely adopted in developmental
psychology.
Tinbergen's four questions for ethologists
Lorenz’s collaborator, Niko Tinbergen, argued that ethology
always needed to pay attention to four kinds of explanation of any
instance of behaviour:
- function: how does the behaviour impact on the animal’s
chances of survival and reproduction?
- causation: what are the stimuli that elicit the response, and
how has it been modified by recent learning?
- development: how does the behaviour change with age, and what
early experiences are necessary for the behaviour to be shown?
- evolutionary history: how does the behaviour compare with similar
behaviour in related species, and how might it have arisen through
the process of phylogeny?
The flowering of ethology
Through the work of Lorenz and Tinbergen, ethology developed strongly
in continental Europe in the years before World War II. After the
war, Tinbergen moved to the University of Oxford, and ethology became
stronger in the UK, with the additional influence of William Thorpe,
Robert Hinde and Patrick Bateson at the Sub-department of Animal
Behaviour of the University of Cambridge, located in the village
of Madingley. In this period, too, ethology began to develop strongly
in North America.
Lorenz, Tinbergen, and von Frisch were jointly awarded the Nobel
Prize in 1973 for their work in developing ethology.
Social ethology and recent developments
In 1970, the English ethologist John H. Crook published an important
paper in which he distinguished comparative ethology from social
ethology, and argued that much of the ethology that had existed
so far was really comparative ethology, looking at animals as individuals,
whereas in the future, ethologists would need to concentrate on
the behaviour of social groups of animals and the social structure
within them. This was prescient. E. O. Wilson’s book ‘’Sociobiology’’
appeared in 1975, and since that time the study of behaviour has
been much more concerned with social aspects. It has also been driven
by the stronger, but more sophisticated, Darwinism associated with
Wilson and Richard Dawkins. The related development of behavioral
ecology has also helped transform ethology. At the same time a substantial
rapprochement with comparative psychology has occurred, so the modern
scientific study of behaviour offers a more or less seamless spectrum
of approaches, from animal cognition, more traditional comparative
psychology, ethology, sociobiology and behavioural ecology.
Notes
There are often mismatches between human senses and those of the
organisms they are observing. To compensate, ethologists often reach
all the way back to epistemology to give them the tools to predict
and avoid misinterpretation of data.
List of ethologists
People who have made notable contributions to the field of ethology:
- W. C. Allee
- George Barlow
- Patrick Bateson
- John H. Crook
- Charles Darwin
- Richard Dawkins
- Vitus B. Dröscher
- Dian Fossey
- Karl von Frisch
- Jane Goodall
- Temple Grandin
- Oskar Heinroth
- Robert Hinde
- Julian Huxley
- Julian Jaynes
- Konrad Lorenz
- Desmond Morris
- Ivan Pavlov
- B. F. Skinner
- William Thorpe
- Niko Tinbergen
- William Morton Wheeler
- E. O. Wilson
- Frans de Waal
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