Zoologists recognised that behaviour patterns are
species specific, and can be used as taxonomical traits.
Whitman: pigeon taxonomy
Heinroth: duck taxonomy
They described behaviour precisely but had no theory to
explain it. Instinct is not an explanation. Is there sepcific
instincts behing every single movement?
Reflex theory (Pavlov)
Few unconditioned stimuli
Few unconditioned response
Any UC sitmus + CS = learns about any new stimulus
Trial and error + US = learns any new behaviour
Plenty of US and UR
Few novel behaviour
species specific behaviour
even learning is species specific
assumed that species specific behaviour patterns are
controlled by specific brain areas. Simple behaviour is
trigered by specific stimulus -> brain centre ->
Stimulus -> response
Direction: independent of stimulus
Paramecium bumps into an object, swims backwards -
direction is changed - then swims forward.
Woodlice prefer dark, damp places, but do not have
the capacity to search for such environment. In unfavourable
conditions woodlice move fast. In damper and darker
area they slow down. In optimal area they stop moving.
Movement behaviour and video tracking of Milnesium
Direction: depends on stimulus
Fly larvae prefer dark places. Swiings its head from
side zo side. If senses light by one eye would turn
its body contralaterally.
Silkmoth females produce bombykol (the first pheromone
characerised chemically), males
approach the females
Attraction of the oriental fruit fly, Dacus dorsalis,
to methyl eugenol
and related olfactory stimulants [pdf]
An aerotaxis transducer gene from Pseudomonas putida
Some of these simple behaviour patterns are reflexes
Action Patterns (FAPs)
FAP is stereotypic behaviour elicited by specific stimuls
(key stimulus), its form is fixed and species specific.
Once started it will be finished and can occur without
the presence of the appropriate stimulus (vacuum activity).
One example for FAP is the egg rolling behaviour of greylag
geese studied by Lorenz (on the left) and Tinbergen (on
the right) together.
goose finishes the rolling movement even if the
egg is taken away. Egg rolling has at least two
distinct components: Pulling the egg is FAP while
the side to side movement of the head to prevent
the egg from rolling off is taxis. .
The egg rolling experiment
FAP was a key concept in early ethology. First of all
demonstrating a large number and variety of unlearned
behaviour in many species helped ethologists to win the
battle with behaviourists who proposed that most behaviour
are learned. Also, the suggestion that FAPs are controlled
by hardwired brain circuitry helped ethologists to propose
mechanism for instinctive behaviour.
Today, however, the term FAP is seldom used. Critics
of the term state that most behaviours are not so much
fixed as previously thought, and are influenced by environmental
stimuli and experience (see Box 3.2 p. 122 in Barnard's).
The fixed form of FAPs, however, is not so much stressed
in the original German expression (angeboren Bewegungsweisen
Erbkoordination) which literally means innate movement
coordination. But then "innate" is also problematic,
many behaviour patterns are the result of interaction
between unlearned and learned components. George Barlow
in 1968 suggested to replace the term FAP with Modal Action
The escape behaviour of the marine Mollusc Tritonia
is trigerred by an approaching starfish, the mollusk's
predator. It consists of several dorsal and ventral
rhythmic flexions which once elicited runs into complition
even in the absance of relevant stimulus.
This study analysed the tongue-protrusion capture
of prey in a lizard species and concludes that it is
not a typical fixed-action pattern, because of it's
variability in performance and duration [full]
Sequential super-stereotypy of an instinctive fixed
action pattern in hyper-dopaminergic mutant mice: a
model of obsessive compulsive disorder and Tourette's
Whether we call behaviour patterns FAPs or MAPs is not
important. What is important whether behaviour consists
of natural units or not. Ethologists assume that behaviour
is built of units therefore behaviour can be described
by the sequence of such elements. This is not merely a
practical issue, because by studying such sequences we
can understand the organisation and evolution of behaviour.
Structure and composition of the courtship phenotype
in the bird of paradise Parotia lawesii (Aves: Paradisaeidae)
Evolution of the courtship phenotype in the bird of
paradise genus Parotia (Aves: Paradisaeidae): homology,
phylogeny, and modularity [pdf]
What kind of stimuli can elicit FAPs?
There were two hypotheses: animals either respond to
a whole pattern or to specific traits of a pattern. In
other words is the whole greater than the sum of the parts
- as Gestalt psychology suggested [wiki],
or the parts independently affect behaviour.
Niko Tinbergen developed an elegant method to systematically
study this question (Tinbergen 1948. pdf).
Basically, he constructed a life-like dummy of the stimulus
he analysed and then systematically changed it to see
which components trigger the FAP. For example, a life-like
male stickleback dummy without red colouration underneath
does not provoke aggression. Dummies of almost any size
or shape with red "belly" will elicit aggression
in male sticklebacks.
Herring seegull chicks peck at the
red patch on the bill of the returning parent to
Niko Tinbergen designed a simple experiment to assess
the specific features of the parent inducing pecking
response in the chicks. What are the releasing stimuli?
Position of patch?
Colour of patch?
Colour of beak?
Are there any learned components?
Seagull chicks beg for food
As chicks vigorously peck at crude modells
made of cardboard it is relatively easy to analise the effects
of the components on pecking rate by systematically changing
stimulus: Colour of the patch
Chicks pecked more at the red patch as illustrated by
Tinbergen in his textbook.
Well, actually, the chicks pecked at the black patch
more than on the red one. Tinbergen reasoned that was
an artifact produced by the experimental design: he presented
the modell with the red patch more often than the other
modells therefore the chicks might have habituated to
it. Carel ten Cate et al. (2009. abstract,
repeated the experiments . When the modells were presented
in a balanced way the red patch was preferred as predicted
by Tinbergen and Perdeck [pdf].
The evolution of the gull chick colour
preference from the original report to the textbooks (ten
Cate 2009. pdf)
Black and white patch on grey beak are preferred. Conrast
itself is important.
Key stimulus: colour of the beaks
Red beaks over the natural yellow are preferred (!)
Key stimulus: movement
The moving modell even without the red patch elicits
more pecking than the stationary head with patch. The
bill is more important than the head. A yellow stick with
three red lines is more affective than the realistic modell.
Key stimulus: position of the patch
The dot on the underside of the lower mandibule elicits
more pecking than the dot on the forehead. Tinbergen concluded
that the chikcs are guided by innate template recognition
Hailman did a series of experiments on herring and
laughing gull chicks and found that the chicks do not
recognise the "template" as Tinbergen suggested,
but simply are attracted to the red patch. As the models
presented were swinging on a pendulum, the patch on the
bill moved faster than the patch on the forehead. Hailman
showed that the speed of the patch rather than the configuration
Hailman main contribution to the gull chick paradigm
was the recognition that experience and learning shape
the pecking response (Hailman 1969. abstract).
Chicks indeed except any oddly shaped model with a beak,
or even a beak alone, however, only for a few days after
hatching. Later the chicks react only to models closely
resembling their parents. The begging behaviouir also
changes with age. First the chicks peck at the beak, later
they rotate theirr head and grasp the beak (as seen in
the video above). Hailman raised some chicks in the dark
and handfed them so the chicks had no experience with
pecking at or grasping the bill of the parents. At the
age when untreated chicks could perform rotating and grasping
Hailman tested the dark reared chicks and found they were
not able to do so.
Tinbergen found that gull chicks prefer a model resembling
their own species and suggested that recognition is unlearned.
Hailman had similar experience with 8 day old chicks,
however, he found no preference whatsoever right after
hatching. Therefore preference of own species is not innate,
chicks learn to recognise and prefer the parents (to see
here - great site on early ethology).
Course materials by Paul Kenyon
A yellow stick with three red lines elicits more pecking
than the natural head. Greylag geese prefer to roll bigger
than normal egg.
The European oystercatcher (Haematopus ostralegus)
retreives an egg so large, she cannot incubate it.
These are examples for supernormal stimuli i.e. a stimuli
which elicit bigger response than the natural stimuli.
Animals in nature seldom encounter bigger than life stimulus
therefore to set an upper limit by the nervouos system
in most cases is unimportant.
However, attraction to supernormal stimuli can be exploited
in many ways. Even when chicks of nest prasite cuckoos
grow larger than foster mother, adults keep on feeding
it (Grim and Honza 2001. pdf).
Humans tend to exaggerate pleasing stimuli and diminish
obnoxious characteristics from food to advertisement.
For example, sweetness of fruits or roots were indicators
of their energy content, therefore preference for sweet
taste was adaptive for early humans. Today industry is
capable to produce concentrated sugar, humans consume
of it in unhealthy amounts. The ability to sense sugar
must be crucial for some species as indicated by the fact
that sugar is highly addictive (Lenoir et al. 2007 html).
Do not follow your instinct (conversation Barrett html)
Examples for key stimuli
Europen robin (Erithacus rubecula) attacks anything
with a red patch on it.
A newly hatched chick approaches any moving object
even after complete telencephalectomy (pdf).
"Besotted beetles are dying while trying to
get it on with discarded brown beer bottles" here
"Female mice respond to male ultrasonic ‘songs’
with approach behaviour" pdf
"Auditory contagious yawning in domestic dogs
(Canis familiaris): first evidence for social modulation
Analysis of key stimuli
What are the components of the key stimuli? Do they act
independently or in interaction?
Tinbergen exploited the egg retreival behaviour to study
preference for shape, size, colour and pattern(repeated
later by Baerends & Kruijt)
Eggs on the horizontal lines are identical in shape and
colouration and different only in size. Larger eggs are
preferred over smaller one. Vertical lines connect equally
preferred eggs. Therefore preference can be directly estimated.
For example vertical eggs connected by vertical line at
1.8 are equally preferred meaning that for the same preference
larger egg is needed if unspeckled. Green speckled eggs
are preferred over natural colouration. For full explanation
and click at page to open it. For a good quality figure
Affectivity of the components of the stimulus pattern
seem to add up independently (heterogenous summation).