Estudoscaninos

CHAPTER 1

Dogs in historical perspective,

and conceptual issues of the

study of their behaviour

1.1 Introduction

This book is about the biological study of dog behav-

iour, based on the programme summarized so clearly

by Tinbergen in 1963. He, Lorenz and others have

always pointed out ç8yy the main contribution of eth-

ology is the biological analysis of animal behaviour

based on observations in nature. Unfortunately,

however, only a handful of mainstream ethologists

have applied these concepts to dog behaviour. In

contrast to sticklebacks, honeybees or chimpanzees,

not to mention a few tens of other species, dogs

received relatively little attention from ethologists or

comparative psychologists. It seems that these crea-

tures ('man's best friends') have somehow become

outcasts from mainstream science, for reasons that

are not obviously clear but which may be guessed.

Dogs are often referred to as 'artificial animals',

probably because their history of being 'domesti-

cated'. Here the image is that of a 'savage' stealing

a wolf cub from its mother (e.g. Lorenz 1954), which

then 'became' dog after many years and generations

in the hands of humans. Today most researchers

disagree with this simplistic view of dog domesti-

cation (e.g. Herre and Rohrs 1990), and it is much

less clear on what grounds the evolution of such

'real' and 'artificial' animals can be differentiated.

The kind of goal-directed selective breeding

implied by the category of 'artificial animal' prob-

ably started much later than has been assumed.

Logically, an 'artificial animal' cannot have a nat-

ural environment, so in order to allow the dog into

the club of 'real' animals we would have to find a

natural environment for it (Chapter 3, p. 42).

The study of dogs did not fit well with the

increasing influence of behavioural ecology, which

was partially initiated by the call for a more func-

tional approach to behaviour by Tinbergen (1963).

Obviously, dogs are not the best candidates for

studying survival in nature, mainly because most

present-day dogs live with humans and have access

to vets, and we do our best to save our companions

from the challenges of nature. In this sense dogs

can be regarded as being special (but not necessar-

ily 'artificial').

More surprisingly, interest in the study of dogs

did not emerge with the cognitive revolution in

ethology. Griffin (1984), one of the initiators of this

movement, seems to have carefully avoided refer-

ence to dogs in most of his works on this subject.

We are introduced to miraculous behaviour of ants,

starlings or dolphins, which we look at with admir-

ation, but similar behaviour in dogs is often regarded

as suspicious. To some extent this attitude is under-

standable, as early workers were often tricked by

so called 'dog artists' who showed remarkable

skills for 'talking' or 'counting' (e.g. Pfungst 1912,

Grzimek 1940-41). (Figure 1.1) After it was found out

that such apparently clever behaviour could be

explained by the dog responding to minute bodily

cues produced either consciously or unconsciously

by the owner or trainer (the Clever Hans effect, see

Pfungst 1907 and Chapter 2.5, p. 37), dogs were ban-

ished from laboratories for being unreliable subjects.

However, it seems that dogs are showing signs of

making a real comeback. Ethologists, comparative

psychologists, and many others are now working

hard to find a place for dogs in the biological study

igure 1.1 (a) Stuppke, a counting dog artist, was observed by Bernhard Grzimek, a German zoologist. Stuppke barked the number shown

to him. The remarkable talent of the dog was based on recognition of a 'start' and a 'stop' signal given by his master, Mr Pilz. (b) No wonder

that Stuppke could also read numbers with his eyes covered (photos taken from Grzimek 1940-41). (c) Oskar Pfungst (1912) reported on Don,

the talking dog (photo from Candland 1993, Oxford University Press).

The Dog at the Convent Door.

Figure 1.2 The 'cultural transmission' of dog anecdotes. Menault

(1869) reports the story of a dog that, after observing beggars

ringing the bell at the door of the convent and receiving some soup,

went to the door and pulled the string. The ability to learn by

observation of humans has only recently been demonstrated

experimentally (Chapter 8, e.g. Kubinyi eta/. 2001 36; Box 8.6).

of behaviour. This is difficult, but the steep increase

in research papers over the last 10 years already

shows the fruit of this work. Thus there is every

chance that dog ethology will revive.

1.2 From behaviourism to

cognitive ethology

Early researchers, including Darwin (1872),

regarded the dog as a special animal that is com-

parable to humans. Many people shared this

anthropomorphic attitude and it is not surprising

that dogs ended up at the top of the ladder repre-

senting intelligence and emotional behaviour in

animals (Romanes 1882a, b) (Figure 1.2). It did

not take long for the situation to change, and

dogs could not avoid their fate when under the

increasing influence of behaviourism they were

then treated as a sort of stimulus-response

automaton. The interest in wolves and social

behaviour in general has helped dogs regain a

foothold in the behavioural sciences, and this has

led to an ethologically oriented understanding of

dog behaviour. The history of the study of dogs

reflects the changes in our views of animals, and

although much time has passed and a lot of

knowledge has been gained, the basic questions

of present-day research are more or less the same

as they were 100 years ago.

1.2.1 Dog heroes visit the laboratory

Dogs have long been the favourite heroes of

animal stories. Sharing our daily life with these

animals has offered endless opportunities to

observe or witness the varieties of dog-human

interactions. One famous collector of such stories

was George Romanes (1982a). His descriptions of

dogs provided evidence for often very intelligent

behaviour which prompted him to argue that

such performances should be explained by

human-like thinking mechanisms (Candland

1993).

Interestingly, Lloyd Morgan (1903), who was a

strong critic of the methods used by Romanes, did

not refrain from telling such stories when he

wanted to illustrate a particular behavioural phe-

nomenon. At one point he describes how his fox

terrier Tony grappled with the problem of how to

carry a stick with unequal weights at its ends. After

describing the dog's behaviour Morgan concludes

that he has seen little evidence for assuming that

the dog 'understood the problem'. Instead, during

repeated attempts to carry the stick the dog learned

the solution by trial and error. Thus 'intelligent'

behaviour on the dog's part could often be based

on relative simple learning processes. For Morgan,

stories provided opportunities for formulating

hypotheses and did not serve as explanations for

mental abilities. Nevertheless he did not deny that

dogs could have a mental representation for an

object, such as a bone.

Thorndike (1911) was among the first to develop

a method to objectively measure learning in ani-

mals. He put hungry cats and dogs into a box which

could be opened from inside by manipulating a

simple latch. Observing the animals repeatedly in

this situation, he found that it took them less and

less time to get out. In agreement with Morgan, he

also thought that the final 'intelligent' behavioural

solution was the result of a step-by-step process of

'trial and error' learning. Thus the systematic

observations of both Morgan and Thorndike

seemed to contradict the conclusions of Romanes,

who argued that, for example, cats and dogs have

someideaaboutthepropertiesof locks.Interestingly,

Thorndike noted a difference between dogs and

cats, because, despite being starved for some time,

dogs were much inferior in escaping. From his

descriptions it seems that, in comparison with the

cats, dogs were less inclined to get out, and they

were also very cautious in interacting with the

latch, which probably indicates a different social

relation between people and these dogs. Thus it is

less surprising that in the textbooks the fame of

representing Thorndike's concept of trial-and-error

learning was left to the cats. From further experi-

ments Thorndike did not find support for the

long-held view that dogs learn by imitation (see

Chapter 8.6, p. 191) because animals did not escape

any earlier from the box if they were shown how to

open the lock.

In 1904 Pavlov received the Nobel Prize for

Medicine for the physiological study of the digest-

ive system, for which dogs had served as subjects.

By this time he had noted that not just the presence

of food in the mouth but also other external stimuli

(the sound of the food put in the bowl or the

approaching experimenter providing the food)

have the potential to elicit salivation. For many

years after that dogs remained one of the most pre-

ferred subjects in the research that led to the devel-

opment of the conditioned reflex principle (Pavlov

1927), which was extended by Pavlov's pupils.

Pavlov was not only a good experimenter, however,

but also a good observer. Thus he noted early on

that there are marked individual differences among

the dogs, which could be also observed in their

response to the training (Teplov 1964). Dogs were

categorized as belonging to one of the classic tem-

perament types described by Hippocrates (san-

guine, choleric, phlegmatic, melancholic) (see also

Box 10.1). Even at that time Pavlov pointed out that

observed behavioural traits are the outcome of

complex processes having both genetic and envir-

onmental components, and he was probably the

first to suggest separating these two effects by rais-

ing dogs in different environments before subject-

ing them to training. The generality of Pavlov's

work on the conditioning reflexes provided the

basis for comparative work on dogs and humans.

Based on this experimental approach, dogs can be

regarded as the first animal models of human per-

sonality (Chapter 10, p. 221). This makes it less sur-

prising that in contrast to some other laboratories

Pavlov's researchers respected the individuality of

the animal. Most dogs were given names, and the

observation of their spontaneous behaviour in the

laboratory or outside was used as additional infor-

mation for understanding their reaction in the

training situations. Importantly, in contrast to

recent research on personalities, Pavlov and his

colleagues based their investigations on single

dogs and then generalized the results to other indi-

viduals belonging to the same personality type.

1.2.2 Dogs in the comparative

psychology laboratory

One cannot avoid being emotionally touched on

reading many of the papers published on dog

behaviour in laboratories working on a Pavlovian

model of learning. Professional scientists, often

having a good 'personal' relationship with these

dogs, often do not seem to realize what they are

doing. There is no way that anyone today could or

would do many experiments like these. The purpose

of reviewing these experiments is to show how the

lack of ethological thought can misdirect scientific

efforts.

A subjective survey of the literature shows that

by the 1920s rats and pigeons had become the main

subjects of research. Thus we might wonder why

some research programmes seemed to prefer dogs.

Having adopted a clearly anthropocentric pro-

gramme in looking for appropriate animal models

of human behaviour, we could reason that for some

features of human behaviour dogs seemed to offer

a more appropriate model. By doing this, these

researchers have implicitly acknowledged that

dogs are more similar to humans than are other

species. Indeed, in discussing dog behaviour they

often relied on comparison with humans (children),

assuming similar underlying mental mechanisms

(e.g. Solomon et al. 1968, see Box 1.3). Interestingly,

this argument was not extended to subjective

states. Thus the dogs' suffering in many of these

experimental procedures was never really a con-

cern.

Another important aspect of these experiments

was that the experimental context had very little, if

any, relevance to the natural behaviour of the dog,

and there was very little correspondence between

the experimentally manipulated variables and the

variables that may relate to a natural situation. The

presence of humans was also confusing for the

dog, because the good/positive social relationship

before and after the experiment was contradicted

by the role of humans in the training trials.

One aim of this research was to provide a behav-

ioural model for neurosis, or traumatic experience

(Lichtenstein 1950, Solomon and Wynne 1953). For

example, dogs were shut into an experimental

chamber and exposed to electric shock ('helpless-

ness': Seligman et al. 1965). After this experience

they were tested in a task in which they were given

the possibility of avoiding similar shocks by escap-

ing from the dangerous place. Many experiments

found that after such an experience the dogs did

not learn. They showed low responsiveness and

seemed 'to give up and passively accept' the shock

(Seligman et al. 1965). We might question the etho-

logical basis of this behaviour. Is there a natural

situation when dogs experience such pain? The

most likely, if not only, situation is when a domin-

ant conspecific inflicts a physically dangerous

attack finished off by a persistent bite. In such a

case the attacked animal's only chance is to show

all possible signs of submission with as little move-

ment as possible ('freezing'). Some of the dogs

might have associated painful experience with

their interactions with humans, which certainly

contributed to the dog's 'neurosis' apart from the

effect of their lack of control over the situation

(Seligman et al. 1965).

A better aspect of this period is that many early

studies provided a detailed description of the dogs'

behaviour, and it became obvious that their reac-

tions to the treatments were very variable. This

suggests that despite being 'laboratory dogs' ani-

mals differed in their previous experience, includ-

ing their relationship with the humans inside or

even outside the laboratory. A further important

lesson from these studies is that training methods

using painful punishments can have unforeseeable

(and mostly negative) consequences on the behav-

iour of dogs, either because of their genetic endow-

ment or their earlier experience with humans

(socialization).

These traditions of comparative psychology were

left behind when more ethologically inspired ques-

tions dominated laboratory research (Figure 1.3.).

Figure 1.3 Dogs under study, (a) A dog in a Pavlovian stand as

illustrated in Woodbury (1943). The dog is trained to recognize

differences in acoustic sound patterns, (b) An illustration from

Jenkins eta/. (1978) showing 'Dog 7'which after being conditioned

to the light stimulus (at the front) signalling food, displays a range

of social behaviours towards the light stimulus and the food tray

(behind the dog, not shown on the illustration).

In 1978 Jenkins and co-workers contrasted the

Pavlovian stimulus substitution theory (Pavlov

1934) with the ethological analysis of the dog

'begging' for food (Lorenz 1969). Pavlov's theory

assumed that the (conditioned) stimulus (e.g. light

or bell) signalling the food will actually replace the

original (unconditioned) stimulus (e.g. food); that

is, when it sees the light come on the dog displays

preparatory acts which reflect consummatory

actions towards the conditioned stimulus (e.g. lick-

ing, snapping at the light). In contrast Lorenz

argued that the conditioned stimulus acts as a

releaser for appetitive behaviours. Thus the dog

searches for the food or displays 'begging', as when

pups solicit food from older conspecifics. Jenkins

et al. (1978) trained dogs to approach a lamp which

signalled the presence of a food reward. In the

course of the training dogs showed very variable

behaviour, but nevertheless many social behaviour

patterns emerged, such as play signals, tail wag-

ging, barking, nosing. Thus we could argue that

dogs interpreted the experimental situation in a

social context with which they were familiar. For

them the conditional stimulus (light) was not just

signalling the arrival of food but it was also a social

stimulus. In this more natural context, 'request' for

food (from humans) is usually preceded by some

sort of signalling (e.g. tail wagging, barking) and

behaviour actions (e.g. nosing, pawing). These

motor patterns are derived from the species-specific

behavioural repertoire of the dog, which is later

modified during the period of socialization. The

social experience and habitual behaviour of the

individual dogs markedly influences the behav-

iour during these observations. The important con-

clusion is that 'one must examine how dogs react to

natural signals of food outside the laboratory set-

ting' (Jenkins et al. 1978)—one of the first signs of a

need for collaboration between comparative psy-

chologists and ethologists. Such an approach opens

up a new way of combining methods that rely on

controlled laboratory settings with those that

emphasize observations on natural behaviour,

including knowledge of the individual's previous

experience.

1.2.3 Naturalistic experiments

Especially during the first half of the last century,

dogs were popular subjects for investigators who

rejected arbitrary laboratory observations. This

work, which culminated just before the Second

World War, was mostly carried out in Germany and

the Netherlands. These researchers continued the

tradition of Morgan and others recognizing the

importance of controlled (more or less) experi-

ments, but they wanted to rely, to a greater extent,

on the natural behaviour of dogs. Many of them

were pupils or followers of Kohler (1917/1925),

who emphasized the role of 'insight' in solving new

problems, and Uexkull (1909), who stressed the

importance of recognizing the features of the nat-

ural environmental (Umwelt) of the animal under

study. Importantly, both Kohler and Uexkull had a

marked influence on early ethological thought

(Lorenz 1981), thus to some extent Buytendijk and

Fischel (1936), Sarris (1937), Fischel (1941), Grzimek

(1941) and others can be regarded as forerunners of

present-day dog ethologists. Although most of their

experiments were performed in the laboratory or in