AMER. ZOOI.., 14:427-430
(1974).
Social Play in the Domestic Cat
MEREDITH WEST
Department of Psychology, Cornell University, Ithaca, New York 14850
SYNOPSIS. The social play of domestic cats in the laboratory and at home was examined.
Categories and sequences of motor patterns were identified and analyzed. The developmental period during which social play was most frequent was established to be from
4 weeks to 4 months. The results suggest that social play functions to provide specific
forms of exercise and as a means of developing and maintaining social relations among
littermates. The decline in social play appears to be related to dispersal of the young
and to a decrease in preference for social contact.
METHODS
INTRODUCTION
The topic of animal play has a curious
history. For many years, play received extensive theoretical attention, but little
experimental study (Muller-Schwarze, 1971).
Theories abounded with respect to play's
important contributions in aiding the
young animal to learn about itself and its
environment (Loizos, 1967). Although animal play is now beginning to be studied in
a variety of mammalian species (Chepko,
1971; Farentinos, 1971; Steiner, 1971;
Bekoff, 1972), the importance of play seems
to be suffering a theoretical reversal. Even
before the data are in or analyzed, recent
writings have now dismissed play as an invalid or scientifically useless categorization
of animal behavior (Berlyne, 1969; Welker,
1971). It was the purpose of this study to
examine social play activity in the domestic
cat and to explore its usefulness as an explanatory concept. This examination included identification of patterns of motor
behavior associated with social play, description of developmental changes in play
and analysis of some aspects of the structure
of social play. The results indicate several
ways in which social play may be beneficial
to the young kitten.
This research was supported by N.I.M.H. predoctoral fellowship award 1 FO1 MH54706-01. I
thank Dr. Robert E. Johnston for his invaluable
assistance in the preparation of this manuscript.
427
The subjects in this study were 28 domestic cats that were studied for durations
ranging from 12 weeks to 7 months over a
period of 2 years. All were observed from
birth. These animals constitute six litters
obtained from four mothers, two of whom
produced two litters. The mothers were
kept with their young for the duration of
the study.
Due to the fact that the domestic cat, by
virtue of its relationship with man, has
been subjected to a broad range of living
conditions, it was felt necessary to utilize
several locations for this study. Fourteen
kittens (3 litters) and their mothers were
studied in the laboratory, where their movements were restricted to a 30 ft by 20 ft room
and an indoor exercise area. Fourteen kittens (3 litters) and their mothers were
housed in the observer's home in a rural
area where they were permitted unlimited
access to the outdoors by means of a special
entrance which the cats could control. The
mothers of the home-reared litters all
"chose" to give birth indoors and to keep
their young indoors for the first 6 weeks.
The methods of care and observation were
essentially the same for all litters.All the
cats were fed twice a day at 8 AM and 4 PM.
Their diet included milk, cottage cheese,
Purina canned cat food, and Purina Cat
Chow. The Purina Cat Chow and water
were always available.
Observations were also made on three
MEREDITH WEST
428
feral mothers and their seven young. These
cats lived exclusively outdoors, had no
permanent indoor residence or formal attachment to humans. Due to the difficulties
associated with observing these individuals,
systematic data were hard to gather. Observations on these cats were made primarily
to obtain information on the duration of
the parent-young relationship and the use
of space by the mothers and kittens.
Observations were made daily on each
litter for a period of 90 min, beginning on
day 14 after birth. This observation period
was always preceded by a variable period in
which the animals were fed, handled, and
their quarters cleaned. Observations on any
one litter were made at the same time every
day. This time, however, was varied across
litters.
During the observation period, written
records were made on the following aspects
of play behavior: description of the types of
motor patterns used during social play,
records of the content of social play encounters between kittens (what motor patterns were seen), records of when play motor
patterns first appeared, measurement of the
frequency of play within the observation
period, and description of play activity between kittens and inanimate objects. An
attempt was made to sample behavior of
each kitten within the litter equally during
each session.
RESULTS
Preliminary observations revealed that it
was possible to identify eight categories of
motor patterns associated with social play.
These patterns constitute the building
blocks for play. The structure of social play
is created through the combination of these
patterns into sequences involving several
patterns and involving two or more kittens.
Before discussing these sequences, a brief
description of the patterns will be given.
The first pattern defies any simple designation. The kitten lies on its back, its belly
up, with all four limbs held in a semivertical position. The tail is straight back
and may be moved back and forth. Typical
paw movements associated with the belly-
up (BU) posture are to move the back legs
in a treading motion and to make reaching
or pawing movements with the front legs.
The mouth is held open and the teeth are
exposed. In a social encounter, one kitten
assumes the belly-up position and another
kitten stands over it. Thus, the treading
and pawing movements bring the kitten into contact with parts of the body of the
standing kitten. Usually, these areas are
the head, neck and ventral area.
The second pattern in the stand-up (SU)
position just mentioned. The kitten stands
near or over another kitten with its head
oriented toward the head and neck region
of the other kitten. The stand-up kitten's
mouth is open and it may direct "bites"
toward the other kitten. The kitten may
also raise one of its front paws and paw at
the other kitten.
The belly-up and stand-up position are
often exchanged by two interacting kittens,
so that they move as one tumbling unit as
the exchanges are made.
The third pattern is a face-off (FO). A
kitten sits near another kitten and hunches
its body forward, moving its tail back and
forth, and lifts a front paw and moves it in
the direction of the other kitten. The kitten's head and eyes are also oriented toward
the other kitten. Two kittens may face-off
simultaneously and direct their front paw
movements at one another's face.
The fourth pattern is a vertical stance
(VS). A kitten assumes a sitting position
and then rocks back on its hindquarters,
lifts its front paws off the ground and
stretches them out perpendicular to its
body. The kitten also extends its back legs
so that it is in a stationary bipedal position.
The fifth pattern is a horizontal leap
(HL). The kitten assumes a lateral position,
with respect to another kitten, arches back
slightly and curves its tail upwards and
towards its body then leaps off the ground.
The sixth position is somewhat similar.
The kitten arches its back, curls its tail upwards and walks sideways toward or around
another kitten or object. This is called a
side-step (SS).
The seventh pattern is a pounce (P). The
kitten crouches with its head held low or
429
SOCIAL PLAY IN THE DOMESTIC CAT
touching the ground and its back legs
tucked in and its tail straight back. The tail
may be moved back and forth. The kitten
moves its hindquarters back and forth and
moves forward, the thrust coming from the
extension of its back legs.
45
a
o
o
30
FIRST POSITION
hi
U
a
S
15
POUNCE
SIDE-STEP
BELLY-UP
STAND-UP
FACE-OFF
VERTICAL
STANCE
HORIZONTAL
LEAP-
CHASE
HORIZONTAL
LEAP
CHASE
HORIZONTAL
LEAP
CHASE
ui
u
MIDDLE POSITION
a
K
o
o
30
o
z
111
15
POUNCE
SIDE-STEP
BELLY-UP
STAND-UP
FACE-OFF
VERTICAL
STANCE
LAST POSITION
u
a
K
13
u
o
30
o
z
Id
O
K
U
15
POUNCE
SIDE-STEP
BELLY-UP
STAND-UP
FIG 1. Per cent occurrence of play patterns in (a)
the first position, (b) the middle position, or (c) the
FACE-OFF
VERTICAL
STANCE
last position at six weeks of age.
MEREDITH WEST
430
The eighth pattern is a chase (CH). Of
all the patterns, this one moves the animal
through the most area. A chase involves a
kitten running after or from another kitten.
It could, perhaps, be differentiated into
pursuit and flight.
The categories of play behavior just described typically appeared in sequences. In
order to gain information about the structure of these sequences, shorthand records
were made on 2500 sequences involving two
kittens. The records were compiled from
observations of 22 kittens, 13 males and 11
females from five litters, three reared in the
lab, two at home. The ages ranged from
4y2 weeks to 16 weeks. A sample of such a
record is given below:
Kitten One: P BU SU FO SU VS CH.
Kitten Two: VS BU FO B BU HL.
These records provided information on
the number of patterns within a sequence,
the frequency of particular patterns and
positions of the patterns within sequences.
With respect to the number of patterns
within a sequence, there was an increase
from a mean of 4.8 patterns per sequence at
6 weeks to 8.1 patterns/sequence at 12 weeks.
Differences in ordering of patterns within
sequences were also apparent (Fig. 1). At 6
weeks, 90% of the sequences were initiated
with one of four patterns, belly-up (13%),
stand-up (15%), side-step (20%) and pounce
(42%). At 12 weeks, four patterns also accounted for 94% of play initiation, but
there were differences with respect to which
patterns were used. Side-steps were used
only 3% and vertical stances, which had
been used only 8%, were now used 24%.
The proportions of pounces (37%), bellyup (16%), and stand-up (17%) were similar
to those at 6 weeks. Although all patterns
appeared during play sequences (as contrasted with the first or last position), several patterns were used more frequently.
Belly-up and stand-up patterns accounted
for 57% of the patterns used during a sequence at 6 weeks and belly-up, stand-up,
and face-offs accounted for 63% at 12 weeks.
Pounces, which occurred with high frequency as a first pattern, appeared only 7%
during a sequence and were never used as
the last pattern. Chases and horizontal
leaps appeared as the last pattern for 70%
at 12 weeks.
Chases and face-offs were not used to
initiate play. The side-step also declined to
a very low percentage in any position at 12
weeks.
Since social play typically involved two
kittens, an attempt was made to see how the
TABLE 1. Proportion of play patterns used in response to play initiation.
Play
pattern of
initiator
Belly-up
Stand-up
Pounce
Side-step
Vertical
stance
Chase
BU
SU
.30
.62
52
.12
.40
20
.05
.43
.10
P
Play pattern used in response
SS
FO
VS
HL
CH
.19
.15
.50
20
.30
.30
Other*
.11
.18
.08
.25
.13
.17
.40
.30
CH
Other
C weeks
• The category "other" refers to any non-playful response.
Belly-up
Stand-up
Pounce
Side-step
Vertical
stance
Chase
BU
SU
.11
.55
.51
.38
.10
.03
.49
.45
SS
.05
.35
FO
VS
25
.11
.10
HL
.12
.19
.12
.45
25
.05
25
.16
.12
.10
.20
21
.30
12 weeks
SOCIAL PLAY IN THE DOMESTIC CAT
performance of one kitten affected the
other. It was only possible to look at this
effect with respect to the initiation of social
play (Table 1). The response of a kitten to
play initiation appeared to be affected by
the pattern used by the initiator. If a kitten
was pounced upon, for example, it responded most often with a belly-up or
vertical stance. Initiations involving either
a belly-up or stand-up usually resulted in
the performance of one of these same two
patterns, e.g., stand-ups occurred in response to a belly-up 62% of the time at 6
weeks and 55% at 12 weeks. Other patterns
appeared to be used infrequently regardless
of the initiating pattern; for example,
pounces never occurred as a response to
play initiation, while chases, horizontal
leaps and face-offs occurred only a small
proportion of the time. (Table 1).
During play sequences, there was rapid
alternation of patterns. The most striking
regularities were that belly-up and stand-up
patterns were found to occur frequently in
combination with one another. If a bellyup occurred, a stand-up followed it 67% of
the time that any playful response occurred.
A stand-up was followed by a belly-up 63%
of the time. A face-off was seen in combination with a belly-up or stand-up 47% of the
time.
The different play patterns first appeared
at different ages (Table 2). The first to be
observed was the belly-up which appeared
at the beginning of the fourth week, around
day 21. AH play patterns, with the exception of the stand-up, were first observed in
a solitary context, i.e., the movements were
not directed toward another kitten.
Upon emergence, the patterns were frequently repated over and over again. The
TABLE 2. Ages at which the play patterns were first
observed.
Play patterns
1.
2.
3.
4.
5.
6.
7.
8.
Belly-up
Stand-up
Vertical stance
Horizontal leap
Pounce
Face-off
Side-step
Chasing
Age first seen
21 -23 days
23-26 days
35-38 days
41-46 days
33-35 days
42-48 days
32-34 days
38-41 days
431
first sequences of patterns thus contained
only repeated performances of the same
pattern, such as twelve side-steps. Sequences
involving more than one pattern and more
than one kitten first occured at 5 weeks.
The content of these sequences was made
up of 50% belly-up and stand-up patterns
and 30% pounces and 20% chases. They
contained an average of four patterns per
kitten. By 6 weeks, the sequences contained
all the patterns, but face-offs and vertical
leaps occurred infrequently (Fig. 1).
Social play sequences often involved more
than two kittens during the fifth through
the eighth week. At 5 weeks, 28% of the
social sequences involved three or more kittens. At 6 weeks, the percentage was 39%,
at 7 weeks, 33%, at 8 weeks, 15%, and by 9
weeks, the percentage dropped to 3% of the
sequences were of this type.
The number of social sequences observed
during a 45-min interval also increased with
age. At 4l/2 weeks, each kitten participated
in an average of 2.1 sequences, at 5 weeks,
3.5 sequences, at 6 weeks, 6.5 sequences, and
at 7 weeks, 9.2 sequences. After this point,
the average number of sequences was 9.4
sequences per kitten from 8 to 16 weeks.
Beyond this age, systematic data were not
collected.
The over-all frequency of play also
changed with age (Fig. 2) .This figure shows
the per cent of time spent in play during
observation periods averaged for each week
from 4 to 18 weeks. Beyond this age, the
amount of play seen continued to decline
but systematic observations were not made.
Cats at this age no longer played daily and
thus measures of per cent of time were more
difficult to obtain. The data for Figure 2
were obtained during the observation
period but the kittens also played during
non-observation periods. For all the kittens
in this study, there were three or four daily
play periods. For the three litters studied in
the laboratory, these play periods occurred
at approximately 7:30 AM, 1 PM, 6 PM and
10:30 PM. The length of these periods increased with age from an average of 18 min
at 5 weeks to 46 min at 9 weeks.
There were several events which seemed
to coincide with the decline in social play
432
MEREDITH WEST
6050-
40
30
-
20
-
10 -
13
15
17
18
AGE IN WEEKS
FIG. 2. Per cent o£ time during observation period spent in social play from 4 weeks to 19 weeks.
activity. In both the laboratory and in the
home, kittens began to display changes in
daily activity around 4 months of age. The
amount of time spent in sleep during the
observation period increased from an average of 8 min for 8 to 16-week-old kittens to
an average of 24 min at 16 weeks and 31 min
at 20 weeks. The amount of time spent in a
"quiet, alert" state, i.e., sitting and visually
attending to events in the environment but
not moving, increased from an average of
14 min for 8-to-16-week-old kittens to an
average of 32 min at 20 weeks. Social grooming was a frequent activity in kittens from 5
weeks of age onward and it also began to
decline at 4 months. Kittens, in general,
spent more time away from their littermates, and the activity of the kittens was
less synchronised. If permitted to do so (as
in the three home-reared litters), the kittens
spent more time outdoors. At 12 weeks,
such kittens were outdoors 2 hr a day, by 16
weeks they spent 4i/£ hr outdoors in nice
weather. During these outdoor periods, play
occurred but in smaller proportion to the
time devoted to exploration and hunting.
These two activities accounted for 68% of
the activity of 12 kittens observed daily
outdoors from 15 to 18 weeks of age.
In case of the feral cats observed, it was
noted that each of the three mothers left
her kittens at around 4 months of age. They
appeared to move to another part of their
range and were not observed near their kittens after this time. Thus, by 4 months of
age, the feral kittens had to find all of their
own food. Prior to this time, it was observed
that the kittens remained close to the shelter or area where their mother had reared
them. Several times they were observed
accompanying their mothers when the
mothers went to find food, but most of the
time, the mothers did not permit their
young to travel with them.
At 4i/£ months of age, sexual activities of
males began to appear. Males began to display mounting, neck grasping and sniffing
of the female's genital area. The female
showed no corresponding interest and the
increasingly frequent attempts by the males
to engage in such activity appeared to make
the female less tolerant of any close contact,
including play. Such avoidance continued
until the females began to reach sexual
maturity, around 5y2 months. Males did
not direct any sexual behavior toward other
males.
Although this paper deals only with
social play, it is worth pointing out that
play with objects in the environment and
other solitary play activities, such as tail
chasing, also declined at 4 months of age,
but the decline was more gradual. When
the adults observed in this study played,
they tended to play with objects by themselves. Ten of the adults studied developed
SOCIAL PLAY IN THE DOMESTIC CAT
idiosyncatic forms of play. These consisted
of play with a particular type of object, such
as a piece of string or a ball, play in a
special location, such as under a "favorite"
chair or repeated performances of a particular play pattern such as a vertical stance.
DISCUSSION
The results of this study indicate that the
social play of domestic cats can be divided
into eight categories of motor patterns. The
structure of social play comes from the
organization of these patterns into sequences. Analysis of the sequences revealed
that differences existed with respect to the
ordering of the patterns suggesting that the
patterns may serve different roles. Pounces,
for example, occurred almost exclusively
as opening patterns and thus appear to be
used to solicit play, i.e., to decrease social
distance and initiate physical contact.
Chases and horizontal leaps to be used to
terminate play. The high frequency of
belly-up and stand-up patterns anywhere in
a sequence and the fact that they were used
in combination with one anotther suggests
that the goal of social play for kittens is to
engage in a particular form of physical contact. The developmental changes in play
also indicate this. Play progressed from a
stage of solitary performance of individual
patterns to solitary and then social sequences containing several patterns. The
decline in group play and increase in pair
play might be viewed as further progress in
this direction in that pair play allows more
direct interaction between individuals. In
play involving three or more individuals
the nature of the play patterns allows for
only peripheral interaction by the "third"
member.
The play patterns are quite constant in
form and could be described as performed
at a "typical intensity" as described by
Morris (1957). The appearance of typical
intensity is thought to "enhance the signal
value of movements by making them more
distinctive" (Hinde, 1970, p. 671). The need
for such signalling during play may be due
to the fact that such close and vigorous
433
physical contact could result in injury if the
signals for playful intent were not clear.
One might also view the use of tail movements, which accompany the performance
of some patterns, as a more potentially variable indicator of playfulness, as the tail can
be moved at different rates.
Social play in the cat can thus be described as sieieulyped form of physical interaction between individuals as has been
noted by other observers and has led to the
use of the "play-fighting" to characterize
cat's social play (Ewer, 1968). The results
of this study suggest that the use of such
semi-functional terms should be avoided
until more information is gathered on the
goals of play because it implies a greater
similarity between the two activities than
appears to exist. For example, although
several motor patterns are common to the
two activities (belly-up, stand-up and chase),
these patterns occur in different combinations with other patterns which are not
seen in both situations. During play, bellyup patterns are often preceded by pounces.
During fights, this pattern is never preceded
by pounces but by the "defensive archedback, posture" which never occurs during
play (Leyhausen, 1956). The decline in the
use of the side-step may possibly be related
to its partial resemblance to the defensive
arched back posture in that its use could
cause confusion in interpreting playful or
aggressive intent. In a fight, the two animals
may also display differing motivational
states, such as fear or threat, whereas during
play, both animals appear to be in the same
motivational state. The outcome of a fight
may involve injury to the opponents, flight
of one of the participants or the gaining of
a disputed object, such as food. None of
these factors appear to be relevant to play
suggesting again that the term "playfighting" may be misleading with respect to
the function of play.
The search for the functions of animal
play has a long history, but there is little
experimental support for any of the functional interpretations (Loizos, 1966). The
results of this study are not a sufficient basis
upon which to identify all of the possible
functions of play in cats, but they do sug-
434
MEREDITH WEST
gest several ways in which social play may
function during the period from birth to 4
months. This period can be characterized as
one of social living, dependency upon a
parent for food and protection and confinement of activities to a relatively small area.
The movements of the young are first restricted by the kitten's inability to travel
and later by the necessity that they be available to the female for nourishment and
protection from environmental dangers. It
is while the kitten is living under such conditions that social play occurs as frequent
and regular activity.
The fact that the kittens are living in a
social environment means that they must
develop modes of social interaction. Play
represents one of several modes available to
the young. Others include social investigation and grooming. While it is not possible
to isolate the effects of only play with respect to how it may function to facilitate or
maintain social relations among littermates,
the high frequency of play suggests that it
does help to keep the littermates on friendly
terms and thus helps to keep the litter unit
together which is important for their survival at this time. Grooming, which also
appears to be a sign of friendly relations
first occurs at the same time that social play
does and although it does decline after 4
months, it remains a more frequent activity
among familiar adults than does social play.
Young kittens require physical exercise
for the proper development of their growing bodies. In animals dependent upon a
parent for food and protection, this need
for exercise must be adapted to fit the particular environmental circumstances, such
as a restricted living area. The physical
nature of the social play patterns provides
exercise for many parts of the kitten's body.
Although social play moves the animal
through space, the patterns are also adapted
to promoting physical contact, thus keeping
the kittens together, which is valuable for
the kitten in that their mother can find
them more easily.
The decline of social play at 4 months
appears to coincide with changes in the
environment and in the kitten which may
affect its needs for exercise and social in-
ter action. At 4 months of age, the litter
unit becomes independent from the mother
and members of the litter begin to travel
from the living area. Kittens, at this age,
may also have to obtain their own food.
These factors suggest then that play may
decline because opportunities for social contact may decline, i.e., the kittens may no
longer live together. The fact, however,
that social play in cats living socially in the
laboratory declines at the same time suggests that other mechanisms may be important. Koepke and Pribram (1971) have
reported a similar decline at this age in cats
reared in the laboratory from birth to 6
months. One of the mechanisms responsible
for this decline in play may be the devlopment of sexual behavior which appears to
alter formerly friendly relations among
males and females. Thus play may decline
not only due the tendency of kittens to disperse at this age thus decreasing opportunity, but also due to changing preferences
of individuals for social contact or particular forms of social contact.
It may also be that alternate sources of
exercise affect the decline in play, for example, increased exertion related to finding
food. The fact that kittens have reached
much of their adult size may also affect
their needs for exercise.
Although all of these factors help to
suggest why play may be useful for the
young kitten, they do not explain the significance of the play patterns themselves. Why
have such patterns evolved? The patterns
used seem to be "suited" to a carnivore in
that they emphasize behaviors of pursuit
and capture of objects or peers. Although
there is little comparative data on the patterns used by other species of cats, there is
one instance where the patterns appear to
reflect differences in hunting adaptations.
In the cheetah, young cubs have incorporated into their play a "new slap" which is
used to knock over peers. This pattern is
also used by the adult to knock over prey
(Ewer, 1973). This pattern has not been observed in either prey-catching or play in
other felids. Play in canids also seems to reflect food-getting adaptions. The presence
of various oral manipulatory patterns, such
SOCIAL PLAY IN THE DOMESTIC CAT
as the "scruff bite" or "face bite" (Bekoff,
1972) may be related to some canids' tendencies to bring down prey with their
mouths (Ewer, 1973). Bekoff (1972) also reports differences in the frequency of social
play among canids which appear to be related to whether they are social or non-social
species, a factor which may also reflect the
influence of food-getting specialisations on
social play.
The results of this study indicate two
ways in which social play may function in
kittens. First, social play may provide a
means of developing and maintaining
friendly social relations among members of
a litter. Second, social play appears to provide ample opportunities for physical exercise. The formation and maintenance of
friendly social relations may not only help
to keep the kittens together and reduce
potential social tension but may also provide opportunities for the acquisition of
social communication skills which will be
used in other social situations. For example,
the ability to discriminate between playful
and non-playful approaches would allow
the animal to interpret the behavior of
individuals in future social encounters. The
opportunity for exercise is equally important for the growing kittens. The fact that
the type of exercise gained from the performance of the play patterns stresses movement patterns used in future food-getting
or aggressive situations may make play of
even more value.
Social play is one of several types of play
activity found in the domestic cat. Whether
all of these types can be discussed in terms
of similar function remains to be seen. The
fact that preferences for different types of
play with age, such as a decrease in preference for social play and increase in solitary
play with objects, suggests that the functions of play may differ.
One element that does appear to be common to all types of play in the cat is that
cats seem to enjoy playing. Although the
essentially private nature of this element
may prevent it from being studied objectively, its potential importance must not be
ignored. The fact that play is a pleasurable
activity may explain not only the high fre-
435
quency of play but also changes in preference for types of play activity. Social play
in kittens may be accompanied by a form of
pleasurable or positive feedback which
would result in its frequent repetition.
When, however, the kitten's interest or
"desire" for social contact decreases, social
play may provide less positive feedback.
Thus, the functions of social play may not
only become inappropriate, but also the
performance of social play may become less
rewarding. The need for engaging in a
pleasurable activity may still exist however,
and thus, other types of play activity would
continue to be performed by the adult.
The results of this study suggest that
knowledge concerning the developmental
period during which play occurs is important in order to explain the content and
function of social play in the domestic cat.
As more information is gained on developmental differences among species of cats and
other carnivores, it may be possible to relate differences in their social play to
developmental factors, such as variation in
periods of dependency upon the parent or
the social bond among littermates.
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