A M . ZOOLOGIST, 7:373-381 (1967).
The Evolution of Social Behavior in Dogs and Wolves
J. P. SCOTT
Department of Psychology, Boioling Green State University, Bowling Green, Ohio
SYNOPSIS. Patterns of social behavior in the Family Canidae appear to be conservative traits
in evolution. Darwin's concept of sexual selection may be broadened to "social selection," including all factors in the social environment which exert selection pressure. In a highly social
species, the social environment tends to be stable, generation after generation, accounting for
the stability of social behavioral patterns. The evolution of social behavior is also related to
development, with different and sometimes opposite selection pressures acting at different periods
in life. Some myths and misconceptions regarding dog-wolf behavior are described, and some
problems for future research outlined.
One of the things which distinguishes
different members of the Family Canidae
from each other is the differential development of social behavior. Among the close
relatives of the domestic dog, the most
highly social species is the wolf, and it is
this characteristic which enables us to say
with a good deal of certainty that dogs are
most probably descended from wolves
rather than from other forms, the coyote
and jackal, which normally form no group
larger than a mated pair or, for a brief period, the litter born to this pair.
In the process of preparing an ethogram
for the dog we listed some 90 behavior patterns observed in the laboratory, nursery,
and free situations (Scott and Fuller, 1965).
We then examined the available descriptions of behavior of the wolf, particularly
those of Murie (1944), Young and Goldman (1944), and Schenkel (1947), and
found all but 19 of the same patterns observed in dogs. Most of the missing ones
were minor patterns of behavior that almost undoubtedly do occur in wolves and
had simply escaped observation under field
and zoo conditions. Conversely, the very
few behavior patterns reported in wolves
but not in dogs were those observed in special hunting situations and hence not likely to occur in dogs living under our conditions. The only major behavior pattern of
wolves that has not yet been reported in
dogs is that of a dominant wolf pinning a
subordinate one to the ground by the neck
(Ginsburg, 1965).
We felt justified, therefore, in concluding that the dog could only have been do-
mesticated from the wolf. As further evidence comes in from detailed behavioral
studies of other Canidae, this evidence cannot be given as much weight, although the
data now available for broader comparisons in no way conflict with our original
conclusion. Tembrock (1957) did a detailed ethogram of the red fox and was able
to identify many of the same patterns of behavior as in the dog and wolf, with minor
modifications such as the tone of the bark.
Significantly, Tembrock did not find the
dog-wolf postures of dominance and subordination. Foxes are even more solitary
than coyotes and jackals, and they apparently have never evolved patterns of agonistic behavior which would permit them
to live in larger groups than the mated
pair.
Since the fox belongs to a different genus
from the dog and wolf, we must conclude
that patterns of social behavior, at least
within the Family Canidae, are conservative evolutionary traits.
Let us now consider the evolution of social behavior in relation to natural selection. In this context Darwin chiefly thought
in terms of sexual selection, accounting for
the bright colors of male birds as the result
of rivalry over females. He was not greatly
concerned with the evolution of social behavior itself, and it has been only within
the last half century that naturalistic studies of animal behavior have revealed the
fact that birds and mammals are capable of
developing a high degree of social organization. It is not just man and the social insects that are capable of social behavior.
(373)
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j . P. SCOTT
We can, on the basis of present knowledge, consider sexual selection and other
social factors in evolution under the more
inclusive title of social selection. Selection
is going on not only as a matter of individual survival against physical forces, as competition between species, and as competition between individuals within species,
but also for survival in relation to the social environment. For a highly social animal the social environment may be the
most stable part of the environment from
generation to generation and so exerts a
relatively constant selection pressure over
long periods of time. This constancy
would, in turn, account for the conservative nature of social behavioral patterns
noted in the paragraphs above. The selection pressure exerted by the social environment may be at variance with selection
exerted by other environmental factors. A
well known example is the antlers of deer,
which have no use except during the rutting season in the pushing contests between
males, and are at other seasons of the year
not only a handicap in dealing with predators but are also a considerable drain on
the animal's metabolism. In wolves, the defense of the den and young cubs against
predators such as bears is highly adaptive
from the social viewpoint, since it leads to
the survival of the young, but it has little
benefit for the individual, which may be
injured severely as a result.
From the viewpoint of population genetics the important thing is not the survival of the individual but the survival of
the gene. An individual may survive to a
ripe old-age but unless he succeeds in passing along his genes to the next generation
he will have suffered "genetic death." Opposing selection-pressures should, therefore,
produce a state of equilibrium (Hamilton,
1964).
Genes do not occur as individual entities
but in combinations peculiar to individuals, in shared combinations in close social
relatives, and in gene pools common to
populations. The processes of selection and
differential survival act at all three of these
levels of organization. Therefore, the survival of genes and organized groups of
genes is dependent on the survival of individuals, of social groups, and of breeding
populations, or species.
In addition to these three different kinds
of selection-pressure, the characteristics of
the social environment may change as the
animal develops. For example, young foxes
live together in a litter of both sexes in the
den of their parents, but as adults they may
be associated with only one other animal,
an adult of the opposite sex, during most
of the year. It is appropriate, therefore, to
examine the evolution of behavior in relation to periods of development. When we
do this, we find that behavior which is appropriate and adaptive at one time in development is not necessarily useful in another.
SELECTION IN RELATION TO DEVELOPMENT
Prenatal development. We have no good
figures for either dogs or wolves on prenatal mortality, but in human populations
this is at least 20% of conceptions, and figures from various domestic and laboratory
animals indicate that the true figure is in
the neighborhood of 40% to 60%. While
some of this mortality is attributed to environmental factors, it is highly probable
that a large proportion of these prenatal
deaths is caused by lethal genes. It would
be interesting to compare the relative figures in dogs and wolves and thus obtain
some indication of the relative levels of
lethal genes in a wild and domestic species.
This could perhaps be done by inbreeding
captive wolves.
Postnatal mortality. Again we have no
figures for wolves, but records of dog populations indicate that a postnatal mortality
rate of 15% is a relatively good one, and
that many breed-populations show higher
rates. Once this period is passed, the death
rates are very low except for accidental
causes. The interesting point here is that
even with a highly protected domestic animal given care nearly as good as that given
to human infants, there is still a relatively
high postnatal rate of mortality. This
means that natural selection has by no
means been eliminated. If we estimate that
EVOLUTION OF SOCIAL BEHAVIOR
375
half the prenatal and postnatal mortality lar phenomenon, including man, and its
is due to environmental factors and fur- theoretical consequences need to be exther assume that the minimal figures given plored. One of these is that behavior in
above are correct, 16% of the original the neonatal period does not necessarily
population at conception has been elimi- lead into or form the foundation for later
nated because of genetic defects by the behavior. Therefore the modification of
time the puppies have passed through neonatal behavior by experience may leave
early postnatal life. The actual figures are adult behavior unchanged. In human deprobably much higher.
velopment it has usually been assumed that
Evolution of behavior in the neonatal each experience is important for that which
period- As indicated above, the neonatal follows, but this is not necessarily so, and
period is one in which a high percentage of it may explain the fact that highly different
mortality takes place and hence a consider- sorts of early infantile feeding and rearing
able amount of selection. If we look at the seem to have relatively little effect on later
behavior of neonatal dog and wolf puppies behavior.
Evolution of behavior in the socializawe realize that their behavior is almost entirely adapted to the conditions of neo- tion period. At the outset of this period the
natal existence. The puppies are born in a puppy is capable of awkward but recognizvery immature state, with both the eyes and ably adult forms of locomotion, feeding,
ears closed. Behavior consists chiefly of and elimination. It also begins to show
nursing, a neonatal form of ingestive be- agonistic social behavior in the form of
havior. Elimination is accomplished in a playful fighting, and a little later, patterns
reflex fashion in response to licking by the of playful sexual behavior. However, the
mother, an adaptation which keeps the nest unique behavior in this period is associated
or den area clean. The puppies vocalize in with the formation of emotional attachresponse to pain or discomfort, and almost ments to places and individuals.
the only other form of behavior is a slow
For a young member of a highly social
crawl, throwing the head from side to side. species, it is essential for survival to form
An isolated puppy will continue this crawl such an attachment rapidly and firmly.
until he touches some warm object, which Evolution has obviously proceeded in this
may be the mother's body or the bodies of direction in the case of the dog and wolf,
litter mates. When the mother leaves the and the process is so fundamental that there
puppies they remain in a close group or is little genetic variation even between dopile, showing only occasional twitching mestic breeds of dogs. All puppies are camovements which probably serve to pro- pable of forming firm attachments to peomote circulation. Investigatory movements ple and places beginning at about three
and nursing are only aroused by tactile weeks of age. While we know relatively
stimulation from the mother when she re- little about this process in wolf puppies, it
turns.
is known that they will rapidly form close
It is obvious that this behavior is adapted attachments to human beings if taken from
for the conditions of neonatal existence in the den soon after the eyes open. The chief
which the mother provides a great deal of difference between dogs and wolves appears
care and protection. There follows a tran- to be the early development in the wolf of
sition period of approximately one week, agonistic behavior which discourages most
during which many of the adult forms of people from adopting wolf puppies at somebehavior appear at least in rudimentary what later ages. However, as Woolpy and
Ginsburg (1967) have shown, it is possible
forms.
We have here a phenomenon which is for wolves to become socialized even as
commonplace in the insects, namely evolu- adults, given prolonged contact with hution toward life in two different habitats, man beings.
As to the behavioral mechanisms inwith a period of metamorphosis in between. Many other mammals show a simi- volved, the chief one is that of distress-
376
J. P. SCOTT
vocalization in the absence of familiar
places and/or individuals. This and the
associated internal reactions have two adaptive functions- In the first place the signal
of distress attracts the attention of parents
or care-taking animals, who are then able
to find the puppy and relieve its distress.
Under natural conditions such distress signals would attract predators as well as parental animals, and it would be interesting
to know how wolf puppies respond in this
respect. Of course, under ordinary conditions the wolf is a dominant predator and
the puppy would be unlikely to wander far
away from the familiar den which the adult
wolves defend as a territory.
The second adaptive function of this behavior is that it reinforces social attachment. Distress-vocalization is almost certainly accompanied by a form of internal
emotional distress, and the puppy must
soon learn that he feels distressed when
away from familiar individuals and objects,
and that this distress is relieved when he
returns to them. This occurs over and over
again in the life of a young puppy and
should result in the formation of a firm social bond.
Evolution of behavior in the juvenile
period. So far I have been talking from a
basis of firmly established facts, but from
now on I must talk chiefly of unsolved
problems. There have been relatively few
observations of wolf cubs during the juvenile period. We know from the work of
other authors in this symposium that adult
wolves show a great deal of flexibility and
adaptability in pack formation. The lone
wolf is a rarity, but wolves can survive as
isolated mated pairs, and packs may range
in size from the relatively small ones observed by Murie in the caribou-hunting
wolves of Alaska to the large pack of moosehunting wolves on Isle Royale described by
Mech (1966).
Murie saw a group of young wolves leave
the parent pack and go off by themselves.
Is this the normal method of pack formation? Also, how do older packs replenish
their numbers as the members grow old and
die, or do such packs simply break up and
disappear?
A further problem is the way in which
the young wolves learn to hunt, especially
if they leave the parent pack at a relatively
early age. Adult wolves feed their young
for long periods, bringing back pieces of
meat which are cached near the den, and
also vomiting food for the young animals.
However, this gives no opportunity for the
young wolf to participate in hunting, and
it is doubtful that wolves at four months
of age would be able to cope with large
prey.
The pubertal period. The sexual behavior of the Canidae is unique in that it
includes the puzzling phenomenon of the
copulatory tie. The mating male and female remain attached to each other in a
helpless and awkward position for many
minutes and sometimes for half an hour or
so. There are reports that early settlers
sometimes hunted wolves in this fashion,
by tying out a female dog in estrus and
then clubbing the helpless male wolf which
mated with her. This contrasts with the
mating behavior of herbivorous animals,
which is usually very rapid and, in the case
of cattle, accomplished within a few seconds. The wolf is, of course, a dominant
predator and seldom attacked, so that its
sexual behavior under most conditions is
not non-adaptive. Even so, the possible
adaptive function is not obvious and needs
to be investigated. This is probably another case of behavior having a social function not correlated with individual survival.
Parental period. Reproduction in the
dog is obviously adapted to the life of a
carnivorous animal, and presumably this
is much the same in the wolf. Implantation is delayed, taking place long after conception, and growth of the fetus is slow until approximately half way through pregnancy. The gestation period is relatively
short for such a large animal, being approximately 63 days. As a result, the female is heavy with young for only a short
period of time.
There follows a period of intense maternal care, which begins to slacken off during the transition period from two to
three weeks, with the result that during the
EVOLUTION OF SOCIAL BEHAVIOR
period of socialization the young are more
and more in one another's company while
the mother leaves for long periods. The
strongest social bonds should therefore be
formed with the litter mates rather than
the mother, and thus should lay the foundation for future pack formation.
In the case of wolves, adults other than
the mother join in feeding the young, and
Crisler (1958) has described a captive yearling pair, not yet sexually mature, vomiting food for young cubs. Food-caching at
the den is also of help to the nursing
mother.
The annual breeding cycle of the wolf
results in the cubs being born in late April
and May, at a time when many of the large
herd animals are also producing their
young and, consequently, food is plentiful.
In most breeds of dogs, the estrus cycles of
females occur at roughly 6-month intervals,
with no relationship to season. An exception is the African basenji, which like the
dingo has an annual cycle beginning near
the autumnal equinox in northern latitudes. Presumably this cycle was modified
from that of the wolf and is adapted to
biotic conditions in the tropics, but we
have no evidence on this point.
MYTHS AND MISCONCEPTIONS CONCERNING
WOLF BEHAVIOR
Before continuing to list some of the important research problems connected with
this species it is appropriate to list certain
issues which now appear to be definitely
settled. Many of these have arisen out of
myths, hunters' tales, folklore, and even
modern romantic fiction.
No authentic cases of "wolf children."
Beginning with the myth of Romulus and
Remus and continuing in modern times
with Kipling's Jungle Books, there have
been repeated stories of young children
who have grown up with wolf packs. From
what we know of the way in which wolves
rear their young it would be impossible for
a young human infant to survive even if a
female wolf adopted it. Wolves and dogs
nurse their young for approximately seven
weeks and thereafter feed their young on
377
vomited food. The likelihood of a baby
surviving under these conditions is so small
as to be almost nonexistent. The reports
of "wolf children" at the most indicate that
juvenile humans have been seen in the company of wolves (Ogburn and Bose, 1959).
There is no evidence whatever that these
children were actually reared by wolves nor
indeed that they had any close association
with them. These reports come from areas
where poverty and child neglect are common and, assuming that they have any basis
at all, the most probable explanation is that
feeble-minded children were abandoned by
their parents and survived by scavenging.
No evidence of any but wolf ancestry for
the dog. Darwin (1859) thought that dogs
must have come from two species because
of their great amount of variation. However, his statement was based on the early
and mistaken idea of blending inheritance.
He was, of course, unaware of Mendelian
inheritance and mutations as sources of
variation within a species. The hypothesis
of dual ancestry has been repeated in a
popular book by Lorenz (1955), who even
attempted to identify "jackal breeds" and
"wolf breeds." Aside from the fact that historical evidence shows that cross-breeding
has taken place between most, if not all
European breeds in historical times, the
behavioral evidence is overwhelmingly in
the direction of pure wolf ancestry. Wolves
are highly social animals, as are dogs,
whereas jackals are like coyotes, ordinarily
forming groups no larger than a mated
pair. Dog vocalizations and wolf vocalizations are very similar and include nothing
like the complex vocalization patterns of
the jackal (Van der Merwe, 1953). The
latter evidence convinced Lorenz, and he
has withdrawn his hypothesis of jackal ancestry.
The other possible ancestor of the dog is
the coyote of North America, and here our
negative evidence is less complete since almost all of the native Amerindian dogs
have become extinct. However, no present
domestic dogs show the peculiar vocalization pattern of the coyote.
Incidentally, Darwin also concluded from
trappers' and hunters' reports that wolves
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J. P. SCOTT
never bark, and if they did they must have
learned it from dogs. All modern observers
agree that wolves bark no matter how near
or remote from domestic dogs. The basis
of this myth is simply that barking is an
alarm signal normally given only near the
den, whereas howling is a form of communication employed on the hunt, chiefly
by animals that have become separated
from the pack and are re-establishing connections. Human hunters are therefore
much more likely to hear wolves howling
than barking. It is also undoubtedly true
that many breeds of dog bark more than
wolves, having probably been selected for
their tendency to bark frequently.
Since dogs are capable of fertile crossing
with both coyotes and jackals, we cannot
rule out the possibility that such crosses
may have taken place in the past. However, even if this is true, the proportion of
jackal or coyote genes has never reached
noticeable proportions. In general, all evidence is in favor of domestication of the
dog from a local population of small
wolves somewhere in the Near East or Central Europe. Although modern experimenters such as Ginsburg (1965), Fentress
(1967), and Murie (1944) have demonstrated how easy it is to domesticate a wolf
pup, it is highly likely that domestication
took place only once. The universal occurrence of sickle-shaped or curly tails in domestic dogs indicates that all domestic dogs
have a common ancestor. This mutation
probably occurred early in the history of
domestication and was preserved because
it was useful as a method of distinguishing
wild from domestic animals.
ATo attacks on human beings by North
American wolves. According to European
folklore, wolves are fierce, slavering animals with red eyes that attack human beings on sight, and there are many American
stories of persons who have been frightened
by wolves. Investigating these stories,
Young and Goldman (1944) were able to
find only one authentic case where a wolf
actually attacked a human being, and this
was a case where a girl was milking a cow
at dusk, and where the wolf might understandably have confused the girl and the
cow. Wolves do hang around hunting
camps and eat refuse and offal and they
have been known to follow persons on foot,
but never to have actually attacked them.
This raises the question as to whether
the reputation of European wolves is based
on fact. Dr. Pulliainen (1966) assures me
that authentic cases of wolves attacking and
killing people have occurred in Finland
and Russia within recent years. If so, the
North American and European wolves
must be different from each other in their
predatory behavior. On both continents
men and wolves often occupy the same ecological niche as hunters of the large herd
animals, and so compete with one another,
competition being intensified when these
same herd animals are domesticated and
thus become the helpless prey of either species. Men prey on wolves on both continents, but why should only the European
wolves prey on men?
This raises a more general research problem, namely, how different are North
American and Eurasian wolves in other respects? All taxonomists agree that they are
the same species, but the two populations
must have been separated for many thousands of years with little interchange of hereditary material across the Bering Strait.
One would expect that the wolves of Northern Europe and Greenland would be most
different from each other. Although geographically close they are genetically connected only tenuously through the distant
Bering Strait.
No exposure of vital parts by subordinate
animals. Lorenz (1955) has suggested that
the loser of a fight, or a subordinate animal, exposes the jugular vein in his neck
to the dominant individual. I have observed dogs living in groups for over 20
years and recorded many different forms of
behavioral adjustment between subordinate and dominant animals. Neither in
these laboratory animals nor in street clogs
have I ever observed anything that could be
interpreted as exposing the jugular vein.
Rather than exposing vital parts, the subordinate animal tends to take up defensive
and protective postures. Instead of the
jugular vein, the dominant dog is most
EVOLUTION OF SOCIAL BEHAVIOR
likely to be presented with a mouthful of
snapping teeth. Schenkel, in this symposium, shows how this misconception may
have arisen in the case of wolves.
.
379
On the other hand, as Rausch (1967) has
shown in an Alaskan game management
area, wolves can populate an empty area
quite rapidly.
This is an appropriate place to mention
some of the discrepancies between the reSOME PROBLEMS OF SOCIAL EVOLUTION
ports of wolf behavior by hunters and manIN WOLVES
agers of control programs and the accounts
Variation and polymorphism. Numerous of workers who study wolves closely and
reports indicate that wolves are morpho- with a minimum of disturbance. The latter
logically variable (Jolicoeur, 1959). Murie report wolves as generally friendly, coopera(1944) was able to recognize easily different tive, and peaceable within their own packs,
members of the pack he studied by differ- whereas the former are likely to report
ences in color and appearance. Further- cases of destructive aggression and even
more, there are large differences between cannibalism. The probable explanation is
local populations. One thing that we do that hunters and those working with connot know is how much variation exists be- trol programs are inevitably observing the
tween individuals and how much variation effects of a disruption and breakdown of
in social organization occurs in different social organization which they themselves
populations and under different environ- have brought about. This is also an apmental conditions. We have reports of a propriate place to reiterate the necessity of
great deal of variation in pack size but marking animals in the field so that they
otherwise little detail, except that Allen can be identified. Without knowing the
and Mech (1966) believe that the so-called identity of individuals and the social rela"lone wolf" has a short life under the con- tionships between them, it is impossible to
ditions in which their pack was studied.
interpret their behavior in any but hypoInbreeding. The degree of inbreeding thetical ways.
within a social group is obviously related
Scent posts and territoriality. Both dogs
to the evolution of local populations. This and wolves make extensive use of scent
problem can only be solved by identifying posts, and both guard small areas around
the individuals within a pack and follow- their dens or living places. Many persons
ing them over a period of years. This prob- have alleged that scent posts are used to
lem is also related to that of pack forma- establish boundary lines which are retion. If the normal method of forming a spected by other individuals. There is no
new pack is for a litter to move out in a evidence that domestic dogs respect such
body from an old pack, there will obviously marks as boundaries, and the usual reacbe a high degree of inbreeding. On the tion of any dog is simply to add his own
other hand, if packs are formed by individ- contribution of urine or feces. Such scent
uals from several packs, the inbreeding co- posts do communicate the estrus condition
efficients will be low. The evidence we have of females, and the most plausible hypotheso far is that packs tend to reject outsiders. sis is to consider this behavior as a form of
Population control. Rabb, Woolpy, and communication which merely indicates
Ginsburg (1967) have found in a group of that a dog has been there recently.
captive wolves that there are rarely over
Whether or not wolves respect scent posts
one or two litters born per year, chiefly be- as territorial boundaries is another quescause the dominant female in the pack will tion, but in view of the enonnous hunting
not allow others to mate. Mech (1966) has ranges used by wolves it is obviously imfound that the Isle Royale pack remains at possible for them to effectively patrol the
a very constant level of numbers. Whether boundaries against intruders. The answer
or not the mechanisms are the same in both to this question should come eventually
cases, it would appear that wolf packs can from the detailed studies of the wanderings
exercise some sort of population control. of wolf packs as described by Kolenosky
380
J. P. SCOTT
and Johnston in this symposium.
Adaptive function of behavior patterns.
There are many patterns of behavior observed in domestic dogs which appear to be
functionless from a human point of view.
For example, dogs frequently turn around
several times before lying down, and this
has been imaginatively interpreted as
tramping down grass or snow. It could just
as easily be imagined that the dog is feeling
the ground for rough places before lying
down. As Tinbergen (1965) has pointed
out, adaptive functions can be verified experimentally and thus become more than
enlightened guesses. One method of verification would be observation of wolf behavior and the designing of some simple
field experimental situations which would
test the resulting hypotheses.
Communication. Wolves obviously communicate a great deal, partly by visual signals arising from body posture and movements, partly through scent, and partly
through vocalization. As howling and barking are studied in closer detail and variations noted, it may be possible to discover
just how much is communicated. It is interesting to note in the report by Theberge
and Falls (1967) that wolves can discriminate easily between recorded vocalization
and the real thing, and that wolves respond
more readily to human imitations than to
recordings. With this kind of discrimination it should be possible for wolves to recognize each other's individual calls. Using
human vocalizations it certainly should be
possible to experiment with intrusions into
the hunting range and thus determine
whether or not it is defended as a territory.
CONCLUSIONS
1. Although complete ethograms are not
yet available for the coyote and jackal, a
comparison of patterns of social behavior
in the dog and wolf leads to the conclusion
that the wolf is the sole ancestor of the dog.
Other evidence indicates that domestication occurred only once.
2. Comparison of fox with dog-wolf ethograms indicates that social behavioral patterns tend to be conservative in evolution;
this is accounted for by the stability of the
social environment from generation to generation.
3. Darwin's concept of sexual selection
may be broadened to that of "social selection," including all factors in the social environment which exert selection pressure.
4. Considered developmentally, evolution of behavior in the dog and wolf has
proceeded in two different directions at different periods of life: toward adaptation
for a highly protected neonatal existence,
and toward adaptation for more independent adult existence.
5. Neonatal patterns of behavior, therefore, do not necessarily lead into adult patterns, and their modification in early experience may have little effect on adult patterns of behavior.
6. Various evolutionary problems are
listed in relation to developmental periods.
The adaptive significance of the copulatory
tie is not understood; this appears to be an
example of a behavioral pattern having a
social function but being somewhat maladaptive for individual survival.
7. Various myths and misconceptions regarding wolf behavior are briefly discussed.
8. A number of basic facts regarding wolf
behavior are still unavailable, such as:
amount of variation in social organization
among local populations, degree of inbreeding in wild populations, social methods of
population control, the degree of territoriality with respect to hunting ranges, the
adaptive significance of many behavioral
patterns observed in dogs, and the effectiveness of vocal communication between individuals and between packs.
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