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Jealousy in Dogs


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It is commonly assumed that jealousy is unique to humans, partially because of the complex cognitions often involved in this emotion. However, from a functional perspective, one might expect that an emotion that evolved to protect social bonds from interlopers might exist in other social species, particularly one as cognitively sophisticated as the dog. The current experiment adapted a paradigm from human infant studies to examine jealousy in domestic dogs. We found that dogs exhibited significantly more jealous behaviors (e.g., snapping, getting between the owner and object, pushing/touching the object/owner) when their owners displayed affectionate behaviors towards what appeared to be another dog as compared to nonsocial objects. These results lend support to the hypothesis that jealousy has some "primordial" form that exists in human infants and in at least one other social species besides humans.
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Jealousy in Dogs
Christine R. Harris*, Caroline Prouvost
University of California San Diego, La Jolla, California, United States of America
It is commonly assumed that jealousy is unique to humans, partially because of the complex cognitions often involved in
this emotion. However, from a functional perspective, one might expect that an emotion that evolved to protect social
bonds from interlopers might exist in other social species, particularly one as cognitively sophisticated as the dog. The
current experiment adapted a paradigm from human infant studies to examine jealousy in domestic dogs. We found that
dogs exhibited significantly more jealous behaviors (e.g., snapping, getting between the owner and object, pushing/
touching the object/owner) when their owners displayed affectionate behaviors towards what appeared to be another dog
as compared to nonsocial objects. These results lend support to the hypothesis that jealousy has some ‘‘primordial’’ form
that exists in human infants and in at least one other social species besides humans.
Citation: Harris CR, Prouvost C (2014) Jealousy in Dogs. PLoS ONE 9(7): e94597. doi:10.1371/journal .pone.0094597
Editor: Elissa Z. Cameron, University of Tasmania, Australia
Received September 12, 2012; Accepted March 19, 2014; Published July 23, 2014
Copyright: ß 2014 Harris, Prouvost. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: This research was not supported by any funding agency. It was performed in CH’s position as a professor at UCSD with volunteer subjects.
Competing Interests: The authors have declared that no competing interests exist.
* Email:
In humans, jealousy is an emotion with far-reaching psycho-
logical and social consequences. For example, it typically emerges
as the third leading cause of non-accidental homicide across
cultures [1]. While the origins and possible function of jealousy
have been debated, most theorists agree on one defining feature: It
requires a social triangle, arising when an interloper threatens an
important relationship. A common assumption has been that the
elicitation of jealousy involves, and perhaps requires, complex
cognitive abilities [2–3], including appraisals about the meaning of
the rival threat to one’s self (e.g., self-esteem) and to one’s
relationship. For example, Lewis [4] has proposed that the
emergence of jealousy requires the cognitive ability to reflect on
the self and to understand conscious intentions.
The vast majority of research in this area has concentrated on
jealousy within romantic relationships particularly over potential
or actual infidelity. Hence, functional or evolutionary analysis of
jealousy has focused on the fitness consequences of loss of a
romantic or sexual relationship (e.g., cuckoldry, loss of resources)
and on the psychological and behavioral effects of protecting such
relationships [5–7]. A broader functional view, however, would
argue that jealousy evolved to secure resources not just in the
context of sexual relationships, but also in any of a wide-range of
valued relationships [1,8]. Accordingly, the same underlying
emotional process that gives rise to jealousy in sexual relationships
also produces jealousy in other types of bonds (e.g., friendships).
One possibility is that jealousy first evolved in the context of
sibling-parent relationships where dependent offspring compete
for parental resources. An implication of this hypothesis is that
jealousy may have a primordial or core form that can be triggered
without complex cognition about the self or about the meaning of
the social interaction [1,9]. This primordial form of jealousy may
be elicited by the relatively simple perception that an attachment
figure or loved one’s attention has been captured by a potential
usurper, which suffices to elicit a motive to regain the loved one’s
attention and block the liaison. Primordial jealousy may serve as
the building block for jealousy elicited by more complex cognitive
processes. For example, in adult human relationships, the
experience of jealousy is greatly impacted by additional appraisals
about the meaning of the interaction (e.g., does this mean my mate
will leave me? Am I unloveable?). In both primordial and complex
cases of jealousy, there is a motivation to restore the relationship
and remove the usurper. However, in the latter case, interpreta-
tions of the situation play a large role in the elicitation and
experience of the emotion.
The theory that jealousy can take a primordial form finds
support from the small but emerging body of research on human
infant jealousy. Several studies [10–12] found that infants as young
as 6-months of age show behaviors indicative of jealousy, for
example, when their mothers interacted with what appeared to be
another infant (but was actually a realistic looking doll). The
infants did not display the same behaviors when their mothers
attend to a nonsocial item (a book).
The functional account we are proposing would further predict
that jealousy should occur not only in humans, but also in other
social species in which emotional bonds between individuals
develop and can be threatened by third parties. Interestingly,
several observers of animal behavior, including Charles Darwin
[13], have suggested that jealousy may exist in other species,
particularly in dogs. This possibility has also been underscored in a
recent paper that had owners recount specific cases of their
animals displaying emotions [14]. Descriptions of dog jealousy
were fairly consistent across owners and always involved a social
triangle. When the owners gave attention and affection to another
person or animal, the dogs seemed to engage in attention-seeking
behaviors (pushing against the owner or in between the owner and
the rival, barking/growling/whining) and some showed aggres-
sion. Reports of the occurrence of jealousy in dogs was at least as
common, if not more so, than some other emotions that are often
considered more primary (anxiety and anger). However, despite
such reports, experimental evidence demonstrating behavioral
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indices of jealousy in dogs does not exist. This type of empirical
research seems particularly important, given that dog owners also
report that their animals experience guilt but experimental work
raises some doubt about whether dogs do show guilt [15].
The idea that dogs are capable of jealousy is congenial to the
burgeoning body of research on animal social cognition that
reveals that dogs have sophisticated social-cognitive abilities. For
example, dogs can use a variety of human communicative signals
(e.g., pointing, eye gaze) to determine the location of hidden food
[16], are better at using social cues than chimpanzees [16], show
some sensitivity to reward inequity when a partner is rewarded
and they are not [17] and appear aware of, and actively attempt to
manipulate, the visual attention of their play partners [18].
The Present Research
Although there are several reasons to predict that jealousy
should lie within a dog’s emotional repertoire, empirical evidence
is lacking. The purpose of the present study was to construct a
social situation and determine whether dogs, whose owners show
affection to a potential interloper, engage in behaviors indicative of
To evaluate dogs’ jealous behaviors, we modified a paradigm
used to assess jealousy in 6-month-old infants [10–12]. Thirty-six
dogs were individually tested and videotaped while their owners
ignored them and interacted with a series of three different objects.
In the jealousy condition, the owner treated a stuffed dog, which
briefly barked and wagged its tail, as if it were a real dog (e.g.,
petting, talking sweetly). In another condition, owners engaged in
these same behaviors but did so towards a novel object (jack-o-
lantern pail). This enabled us to test whether the elicitation of
jealousy required that the owner show affection to an appropriate
stimulus (what appeared to be a conspecific) or whether
affectionate behaviors directed to a nonsocial stimulus would be
enough to arouse jealous behaviors. In the third condition, the
owner read aloud a children’s book, which had pop-up pages and
played melodies. This condition allowed us to test whether dogs’
behaviors in the other conditions were indicative of jealousy per se
(arising over the loss of affection and attention towards an
interloper) or more general negative affect due to the loss of the
owner’s attention.
As discussed earlier, the proposed function of jealousy is to
break-up a potentially threatening liaison and protect the primary
relationship. This motivates several types of behaviors including
approach actions such as attempts to get physically or psycholog-
ically between the attachment 3ure and the interloper, attending
to the threatening interaction, seeking attention from the
attachment figure, as well as indicators of negative emotion such
as aggression, particularly toward the interloper [1–2,8,10–12,19].
Across social species, we would expect to see similar types of
behaviors that serve the function of this motivational state.
Therefore, the specific behaviors assessed in our experiment were
based on studies of jealousy in non-verbal human infants and
adults as well as behaviors described by dog owners and experts as
indicative of jealousy.
This research was approved by the University of California San
Diego Institutional Animal Care and Use Committee and by the
University of California at San Diego Human Research Protec-
tions Program. Owners and pet dogs were recruited from the
University of California, San Diego subject pool. Owners received
partial course credit in psychology class for participation.
Dogs were tested individually at their homes and had to be less
than 35 pounds or shorter than 15 inches. A size criterion was used
because of the possibility that the jealousy manipulation would
result in aggression and small dogs could be more easily controlled
in such circumstances. Upon arrival at the subjects’ homes, the
experimenter obtained written consent from the dog owners for
participation. The experimenter also gave a brief overview of the
study stating, ‘‘For this experiment, we are examining individual
differences in dog behavior across various situations. Thus, we’ll be
asking you to act out various situations in front of your dog, while
ignoring him or her, while we film his or her reaction." The
experimenter also said, "If you think that your dog will act
aggressively in this situation, we ask that you and your dog don’t
participate, but you’ll still receive your Experimetrix [course]
credit." All owners chose to continue with the experiment.
The initial sample size was n = 37. However, one male dog was
excluded from all analyses due to a miscommunication between
the owner and experimenter resulting in one condition ending
prematurely. Therefore, the final sample size was n = 36. The
mean age of the dogs was 32.2 months (range = 4–135). Equal
numbers of male and female dogs participated. The sample
consisted of a variety of dog breeds as can be seen in Table 1.
Owners (31 females and 5 males) had owned their dogs an average
of 25.4 months (range = 1–134).
Owners were not aware of the hypotheses of the experiment. A
within-subjects design was employed with order counter-balanced
across participants. Each experimental condition was videotaped
and lasted for 1 minute, followed by a 30 sec post-condition phase
in which the owner set the object down within reach of the dog.
The owner completed a questionnaire after each condition and
then the dog and owner were given one minute to freely interact in
order to reduce any potential carryover effects from the previous
Stuffed Dog. Owners were instructed to interact with a
realistic-looking stuffed dog that barked, whined, and wagged its
tail (which lasted for a total of approximately 8 secs) when a button
on the top of its head was pressed. The owners were asked to press
the button only once and to interact with the stuffed dog as if they
were playing with a real dog. They were also instructed to
completely ignore their dog, which was present in the room for the
duration of the interaction.
Jack-o-lantern. In the novel object condition (jack-o-lantern),
owners were given the same instructions as in the stuffed dog
condition: to interact with a jack-o-lantern as if they were playing
with a real dog.
Book. In the book control condition, owners were instructed
to read aloud a children’s book, which popped up and played
melodies, as if they were reading to a young child. Total amount of
time the object made a noise was closely matched to that of the
dog condition (approximately 8 secs).
Two raters, blind to the study’s purpose, coded the videos.
Unless otherwise noted, behaviors were coded as present or absent
and are reported as percent of dogs showing such behaviors per
condition. To compute interrater reliability, 29 dogs were coded
by both raters. Behaviors in which interrater reliability was lower
than .7 were not included in the analyses. For analyses that
required whole numbers (i.e., Cochran’s Test for presence/
absence of a behavior), we used one rater’s codes for half the dogs
Jealousy in Dogs
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and the other rater’s codes for the other half. Behaviors coded
during the interaction of the owner with the object are described
first, followed by the behaviors coded post-interaction.
Aggression. We coded for aggression given its link to jealousy
in human adults [1] and in owners’ reports of dog jealousy [14].
Our primary measure of aggression was whether the dog
attempted to bite/snap at the object. Coders also attempted to
code more subtle signs of aggression that include lip curling (lips
being held open with force in order to expose teeth), raised tail–
holding the tail up between the horizontal and vertical positions
(an aggressive posture in wolves), and keeping the ears forward.
Interrater reliability was low for ears forward (.57) and so this
behavior was not analyzed. Our coders also reported difficulty
assessing the raised tail in many dogs due to their physical
characteristics (e.g., a clipped tail); however, interrater reliability
was acceptable, so these analyses are reported in the results
section. Lip curling was not seen across any condition.
Attention Seeking/Disruption of Interaction. The most
common category of behavior in owner descriptions of their dogs’
jealousy was attention seeking [14]. These behaviors often took the
form of pushing the owner or attempting to get between the owner
and the rival. We coded for both of these behaviors. Some owners
also reported attempts by their dogs to shoo the rival away. In our
coding scheme, we operationalized this as the dog pushing against
the rival object. Another class of behaviors categorized as attention
seeking by Morris et al. [14] was vocalizations (described as
barking, growling, and whining), which we assessed. (Growling
interrater reliability was lower than our .7 cutoff so was excluded
from our analyses.)
Interest/Attention. The preverbal human infant literature
(e.g., by Hart and colleagues) suggests that jealousy produces
increased interest and attention toward the mother. We assessed
several behaviors pertaining to attention, which included 1)
looking at the owner, 2) looking at the rival object, 3) orienting
away from the owner, and 4) orienting away from the object. The
first two categories were operationally defined as having the head
turned and gaze directed toward the owner/object; the later two
were operationally defined as having the head and body turned
away from the owner/object. Due to their frequency across
conditions, a simple present/absent code for the entire interaction
period did not adequately capture these behaviors. Therefore, we
performed more fined grained coding that consisted of denoting
whether the behavior was present or absent every 5 seconds,
resulting in total score that ranged from 0–12. Total scores were
then transformed into proportion of time behavior was present. (In
the cases where both raters coded the same dog’s behavior, the
average of the two coders’ scores was used for these measures.)
Behaviors coded during the 30-second post interaction
During the post-interaction period, the owner put the
object down and walked away. We coded four behaviors during
this phase: 1) aggression/snapping directed at the object; 2)
following the owner; 3) observing the object; and 4) ignoring the
object. Due to the laborious nature of coding, we only coded for
presence/absence of attention behaviors (observing/ignoring
object) in this phase rather than assessing attention every 5
seconds as done in the condition phase. Additionally, in the dog
condition, we noted if the dog sniffed the rear end of the toy dog.
This was included as a measure of whether the dog perceived the
stuffed dog as a real dog.
Additional exploratory measures. In addition to assessing
jealousy, we used this opportunity to explore attachment style in
dogs (and its possible interaction with our conditions), which we
mention here for the sake of completeness. We created a scale for
owners to complete regarding their dog’s attachment style and
coded for behaviors that might be linked to different attachment
styles. These included behaviors that might be indicative of anxiety
(paw slightly raised; yawning) and of submission (ears back, tail
down, and licking). We also attempted to code tail wagging to the
left vs. the right because work by Quaranta, Siniscalchi, and
Vallortigara [20] suggested that the former is associated with
withdrawal and the latter with approach. However, our coders
found this too difficult to assess via video. Analyses pertaining to
attachment style are not reported here given their exploratory
nature and the difficulty of measuring some of these behaviors.
Table 1. Dog Breeds.
Boston Terrier 1 (2.7)
Chihuahua 2 (5.4)
Dachshund 1 (2.7)
Havanese 1 (2.7)
Malinois 1 (2.7)
Maltese 3 (8.1)
Miniature Pincher 1 (2.7)
Miniature Schnauzer 1 (2.7)
Pomeranian 2 (5.4)
Pug 1 (2.7)
Shetland Sheepdog 1 (2.7)
Shih-tzu 2 (5.4)
Welsh Corgi 1 (2.7)
Yorkshire Terrier 3 (8.1)
Mix 14 (37.8)
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Results & Discussion
Figure 1 shows the proportion of dogs that engaged in the
various behaviors during the interactions with the objects in each
condition. Our analyses showed significantly greater aggression in
the jealousy condition, Cochran’s Q, x
(2) = 12.80, p, .002. One
fourth of the dogs snapped at the object in the jealousy condition
but only 1 dog did so in the other two conditions. (Results from
follow up McNemar nonparametric tests are presented in Figure 1.)
We, however, did not see a difference across conditions in the
number of dogs that placed their tails between the vertical and
horizontal positions (Cochran’s Q, x
(2) = .67, ns). This may be
due to our coders having difficulty accurately assessing tail
movement (e.g., in dogs with snipped tails). In the post-interaction
phase (when the owner had put the object down), 36% of the dogs
snapped at the stuffed dog while snapping behavior in the other
conditions was confined to one dog (Cochran’s Q, x
(2) = 20.57,
p, .001). The aggression in the jealousy condition is particularly
impressive given that we only tested dogs whose owners believed
that their dogs would not behave aggressively in novel situations.
The next series of analyses examined attention seeking and
specifically focused on the behaviors most commonly noted by
owners when describing their animals’ jealous behaviors [14].
Dogs were significantly more likely to push or touch their owners
(Cochran’s Q, x
(2) = 26.87, p, .001) and the object (Cochran’s
Q, x
(2) = 24.07, p, .001) in the jealousy condition relative to
either the jack-o-lantern or book conditions. Results for follow up
McNemar nonparametric tests are presented in Figure 1. Of
particular interest, dogs specifically tried to get between the owner
and the object more often in the jealousy condition (Cochran’s Q,
(2) = 6.53, p, .04). Such behaviors aimed at preventing or
breaking up a liaison have been hypothesized to be the primary
motivational state that accompanies jealousy and that distinguishes
jealousy from other emotions such as anger [1,19]. Although
vocalizations during the experiment were relatively infrequent,
whining occurred significantly more in the jealousy condition than
in the book condition. Barking did not significantly differ across
At the suggestion of a reviewer, we summed the behaviors
presented in Figure 1 for each condition in order to get a sense of
the effect size of the jealousy condition and performed within-
subjects ANOVA with partial eta-squared tests. Partial eta-
squared for the dog vs. jack-o-lantern conditions was .41 and for
dog vs. book was .58.
In the preverbal human infant literature, jealousy is accompa-
nied not only by negative affect but also by heightened interest and
attention toward the mother while she is interacting with what
appears to be another infant [10–12]. We found similar effects in
dogs. Results for within-subject ANOVAs are presented in the text
while results for follow up paired t-tests are displayed in Figure 2.
As shown in Figure 2, dogs gazed significantly more at their
owners (F(2, 70) = 7.47, p, .001, g
= .18) and the objects (F(2,
70) = 56.39, p, .001, g
= .62) in the conditions in which the
owner was displaying affection towards an object relative to the
control condition of reading aloud. Furthermore, when the object
of affection appeared to be a conspecific, dogs looked more at the
object relative to when it was a novel item (jack-o-lantern). This
pattern is furthered supported by the inversely related measures of
disinterest, operationally defined by orienting the body away from
the owner and object (Figure 2). Dogs spent significantly more
time ignoring the owner and object in the book condition relative
to the conditions that involved displays of affection: F(2,
70) = 30.62, p, .001, g
= .47 for owner; F(2, 70) = 87.27, p,
.001, g
= .71 for object.
Behaviors during the post-task period were similar to those seen
during the actual interaction (although less informative given that
behavior was merely coded as present/absent). More dogs ignored
the object in the jack-o-lantern (94.4%) and book (91.7%)
conditions than in the dog condition (52.8%); Cochran’s Q, x
(2) = 20.01, p, .001. There was also a significant difference in the
number of dogs who observed the object across conditions (72.2%
in dog condition; 63.9% in jack-o-lantern condition; and 44.4% in
book condition): Cochran’s Q, x
(2) = 6.58, p, .04. There was
not a significant difference in the number of dogs who followed
their owner after each condition, x
(2) = 4.67, p = .10.
Figure 1. Comparisons of the proportion of dogs exhibiting each type of behavior in each of the three experimental conditions.
Jealousy in Dogs
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Was the stuffed dog perceived as real?
One might wonder whether the subject dogs believed that the
stuffed animal was a real dog. The data discussed previously,
particularly the aggressive behaviors aimed at the stuffed animal,
would seem to suggest that they did. Perhaps even more
compellingly, 86% of the dogs sniffed the anal region of the toy
dog during the experiment or post-experiment phases. Having a
faux rival dog enabled us to maximize the amount of control we
had in the experiment. That jealousy behaviors were seen under
these somewhat impoverished social conditions leads us to predict
that such behaviors would be even more enhanced in the present
of an actual rival dog who responded to the owner’s affectionate
In the present work any single behavior might not be indicative
of jealousy per se. However, the pattern of behaviors, particularly
when dogs were confronted with their owners displaying affection
to what appeared to be another dog, is similar to the constellation
of behaviors seen in humans. These data thus present a strong case
that domestic dogs have a form of jealousy.
Individual Differences
An anonymous reviewer suggested that our data might reflect
individual differences in dog cognition and/or jealousy. One
possibility is that only some dogs perceived the stuffed dog as real
and that this difference in cognitive ability resulted in jealousy in
some dogs but not others. To the reviewer’s mind, only those dogs
that aggressed against the ‘‘rival’’ dog can be shown to definitively
consider the fake dog stimulus as real. We believe that the fact that
the vast majority of the dogs sniffed the anal region of the stuffed
dog (including all of the aggressive dogs) suggests that most of the
dogs conceptualized the dog as real, but we cannot rule out the
reviewer’s suggestion.
However, even if most dogs perceived the stimulus as real, it is
still possible that only some of them reacted with jealousy to it. The
reviewer suggested some additional analyses to explore possible
individual differences. One question is whether the snapping dogs
were the only ones to show additional jealous behaviors. As
described below, our data suggest that they were not, although
their jealousy might be argued to be more intense in some respects
than their nonsnapping peers. In total, 41.7% of dogs snapped
during or after their owner interacted with the stuffed dog. We
found that these aggressive dogs did display many other jealous
behaviors: All of them pushed at the owner and 86.7% pushed at
the fake dog during the jealousy interaction. There was also some
tendency for these dogs to spend more time (although not
significantly so) attending to the owner and the fake dog (and
conversely less time ignoring the owner and rival) than nonsnap-
ping dogs. However, not all jealous behaviors were more common
in the snapping dogs. Whining was similar across the two types of
dogs and while 26.7% of the snapping dogs attempted to get
between their owner and the rival dog, 33.3% of the nonaggressive
dogs did so. Moreover, many of the nonsnapping dogs also
displayed other jealousy indicators. For example, 61.9% pushed at
the owner and 57.1% pushed at the stuffed dog. These percents
are higher if the dogs that did not sniff the rear end are excluded
(who likely did not perceive the stuffed dog as a threat). Thus,
these exploratory analyses would argue against the suggestion that
only aggressive dogs displayed jealous behaviors, although their
jealousy may be viewed as more extreme. These data raise the
possibility that dogs, like humans, show individual differences in
how jealousy is exhibited, which ranges from attention seeking and
restorative behaviors to aggressive acts.
The fact some dogs (13.8%) failed to sniff the rear end of the
fake dog raises stimulating questions for future studies. Jealous
behaviors were infrequent among these animals, suggesting that
they were not in an emotional state (e.g., none pushed on the
owner or the stuffed dog and only one got between them). One
interesting possible avenue for future work is to examine the
cognitive abilities that are associated with not believing the stuffed
dog is real. It might be that such dogs are less cognitively
sophisticated (they do not perceive the toy as representation of a
real dog.). However, it is also possible that they are more
sophisticated, (i.e., were not fooled into believing that the stuffed
dog was genuine, and hence it was not a threat).
In sum, it may be that while all dogs have the neurobiological
cognitive capacity for jealousy, the current situation may have
failed to induce the emotional state in some dogs. Understanding
what factors (cognition or social dynamics) contribute to individual
differences in dog jealousy would seem a ripe area for future work.
Figure 2. Proportion of time dogs spent attending to and orienting away from their owner and the object in each of the three
experimental conditions.
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Concluding Remarks
The current findings add support to the emerging view [1,9]
that there is a primordial form of jealousy. This emotional state
does not presuppose complex interpretations of the behavior of the
rival and the attachment figure and its meaning to the self,
(although such cognitions clearly can impact jealousy in adult
interpersonal relationships). Primordial jealousy appears not only
ontogenetically early in humans but may also have emerged
phylogenetically early. We use the term ‘primordial’ to reflect a
state that motivates jealous action tendencies that are similar
across dogs and humans (of course, these findings do not speak to
whether the subjective experience of the emotional state is similar).
If jealousy is phylogenetically old, then one might expect to see
some form of it in other animal species that form emotional bonds
that can be threatened by rivals, whether that rival be a sibling, or
a mate, or another group member. Here we tentatively suggest
some possibilities about features that might have given rise to
jealousy, which could be explored in further work.
One possibility is that jealousy evolved in species that have
multiple dependent young that concurrently compete for parental
resources such as food, attention, care, and affection. It is easy to
imagine the advantages that might be gained by a young animal
that is not only alert to interactions between siblings and parents,
but also motivated to interpose itself in such interactions. Several
of the behaviors assessed in the current work (e.g., pushing on the
owner, getting between the owner and ‘‘rival’’ dog) would seem to
serve that goal. Future work might look at how effective these
behaviors are in natural triadic interactions (e.g., does pushing on
one’s mother divert her attention from a sibling?). Another
possibility is that jealousy behaviors emerged to protect pair-
bonded sexual relationships from interlopers. If so, then jealousy
might not exist in species that do not pair-bond, regardless of the
number of offspring reared simultaneously. (To date, little is
known about the relationship between romantic and nonromantic
jealousy.) Finally, it is possible that jealousy evolved in animals that
require cooperation from other group members for survival and in
which alliances are formed (and therefore, can be threatened by
rivals). These possibilities are difficult to tease apart by studying
dogs given that they are litter born, have the potential for pair-
bonding (see Bradshaw [21] for discussion), and hunt coopera-
tively. It would be informative to examine jealousy in species that
differ on these factors (e.g., domestic cats, which bear litters but are
not pair-bonded).
Finally, it is also possible that the long co-evolution and
domestication of dogs, which likely gave rise to many of their
remarkable social-communicative skills [16,22], created their
capacity for jealousy. (Perhaps this is a function of their emotional
bonding with humans along with their motivation and ability to
track human gaze/attention. Humans, afterall, have been rich
resource providers over our coevolution.) One might speculate
that even if several social species have the capacity for jealousy,
dogs may be the only species besides humans in which the emotion
can be evoked in connection with a member of a different species.
Future studies that examine the affective and cognitive abilities of
a variety of animal species could help tease apart these various
intriguing possibilities. Such work is particularly warranted given
that a large percentage of owners of some other types of domestic
animals such as horses, birds, and cats also report signs of jealousy
in their animals [14]. Moreover, some of these species such as
horses have been shown to be highly sensitive to human
attentional cues [23]. Further research on the neurobiological
components of and influences on emotions in both humans and
other animals may also help disentangle the similarities and
differences of emotion and social behavior across species [24–25].
In closing, these findings add additional support to the view that
jealousy can arise in the absence of complex interpretations of the
meaning of the rival and loved one’s interaction and occurs in
another species besides humans. We hope the current work will
inspire further research into the social emotions of animals.
We thank Alison Yee and Wanting Tan for coding the videos and Noriko
Coburn for her assistance with various aspects of the study.
Author Contributions
Conceived and designed the experiments: CH CP. Performed the
experiments: CP. Analyzed the data: CH CP. Contributed reagents/
materials/analysis tools: CH CP. Wrote the paper: CH CP.
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Jealousy in Dogs
PLOS ONE | 6 July 2014 | Volume 9 | Issue 7 | e94597
What really differentiates us from our relatives in the animal world? And what can they teach us about ourselves? Taking these questions as his starting point, Norbert Sachser presents fascinating insights into the inner lives of animals, revealing what we now know about their thoughts, feelings and behaviour. By turns surprising, humourous and thought-provoking, Much Like Us invites us on a journey around the animal kingdom, explaining along the way how dogs demonstrate empathy, why chimpanzees wage war and how crows and ravens craft tools to catch food. Sachser brings the science to life with examples and anecdotes drawn from his own research, illuminating the vast strides in understanding that have been made over the last 30 years. He ultimately invites us to challenge our own preconceptions – the closer we look, the more we see the humanity in our fellow creatures.
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We examined whether dogs show emotional response to social stimuli played on videos. Secondary, we hypothesized that if dogs recognize themselves in videos, they will show a different emotional response to videos of self and other dogs. We compared heart rate variability among four video stimuli: a video of the owner ignoring another dog (OW-A-IGN), a video of a non-owner interacting with another dog (NOW-A-INT), a video of the owner interacting with another dog (OW-A-INT), and a video of the owner interacting with the dog subject (OW-S-INT). The results showed that root mean square of the difference between adjacent R-R Intervals (RMSSD) and standard deviation of the R-R Interval (SDNN) were lower in NOW-A-INT and OW-S-INT than in OW-A-IGN. There was no statistical difference in the responses to OW-S-INT and OW-A-INT, suggesting that dogs did not distinguish themselves and other dogs in videos. On the other hand, the difference in mean R-R Interval between OW-S-INT and OW-A-INT showed positive correlation with the score of attachment or attention-seeking behavior. Therefore, this study does not completely rule out self-recognition in dogs and there remains the possibility that the more attached a dog to its owner, the more distinct the dog’s emotional response to the difference between the self-video stimulus and the video stimulus of another dog. Further studies are needed to clarify this possibility.
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Pet dogs are promising candidates to study attachment-related and potentially jealousy-like behaviours in non-human animals, as they form a strong and stable bond with their human caregivers who often engage in affiliative interactions with diverse social partners. Nevertheless, it is still debated whether non-human animals are capable of experiencing such complex emotions. Even though caregivers frequently report observations of jealousy-like behaviours in dogs, behavioural studies in dogs have thus far led to contradictory results. Adding to this complexity, dogs appear extraordinarily skilled in understanding humans’ communicative behaviour and can flexibly and diversely interact with them in social contexts. Here, we aimed at investigating (1) whether dogs indeed respond in a jealousy-consistent manner when seeing their caregiver interact in an affiliative way with a remotely controlled, realistic-looking fake dog, or (2) whether they would rather synchronize their reaction to the fake dog with the caregiver’s behaviour, or (3) whether they respond directly to the caregiver without paying much attention to the third party. To address what drives the dogs’ behaviours in this triadic situation, we compared four groups of dogs who first observed and then joined the interaction of either the caregiver or a stranger greeting or medically examining the fake dog. We found that the dogs initially responded negatively or neutrally when the fake dog entered the room but changed to more positive reactions when the caregiver approached the fake dog, especially if initiating a positive interaction. When being released, more dogs showed friendly behaviours towards the fake dog when the caregiver—rather than the stranger—was interacting with it. At the same time, however, the dogs tried to block the interaction of the caregiver with the fake dog more often than the one of the stranger. In conclusion, we did not find clear evidence for jealousy-like behaviours in dogs during the human–fake dog interactions, but we observed indicators of behavioural synchronization with the caregivers, suggesting that the caregivers’ affiliative behaviours directed at a third party may more often facilitate positive than negative interactions in dogs.
Emotions are the colours in the tapestries of our lives. They can be positive, feel-good ones like happiness, love and pride, or negative, irksome ones, like sadness, embarrassment or anger. Some people claim that there are no positive or negative emotions. We just need to accept them as we experience them. When we interpret emotions through a functional lens, we can improve our ability to identify them as we experience them, and make informed choices about whether or not they are helpful to us in particular situations. This chapter discusses the functions of our emotions, using findings from both scholarly articles and empirical studies to illustrate their different functions and how they impact our lives. It also discusses how we respond to our emotions, and the defensive mechanisms we use to cope with unpleasant ones.
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Aggression as a behavior is not always desirable, often ends in abandonment and/or euthanasia. However, it is possible to prevent the occurrence of unwanted aggression in domestic dogs. Aggression is not a fully understood phenomenon. In recent years, many studies have focused on the influence of diet and physiology (including the endocrine system) on the emergence of behavioral disorders. In particular, the emphasis was put on nutritional additives such as fatty acids, amino acids, and probiotics. In addition, the possibility of using neurocognition in the observation of abnormal behavior in dogs has also been discussed, which may allow for a more detailed determination of the basis of aggressive behavior in dogs. In this review, the concepts related to aggression and its potential causes have been gathered. In addition, the possible influence of diet and hormones on aggression in dogs has been discussed, as well as the application of neurocognition in the possibility of its diagnosis
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Assumptions about dogs’ personality are influenced by their appearance, which may lead to differences in ownership styles and subsequent canine welfare. The influence of canine appearance on observers’ emotion attributions to dogs remains largely unexplored. This study investigated whether canine head shape is related to how both dog owners and non-dog owning adults in the U.K. attribute emotions to still images of dogs, and in the case of dog owners, to their own dogs. Attachment, respondent personality and dog trainability were assessed as potential influences on emotional attribution in owners. Overall, 2451 participant responses were received. Still images of mesocephalic dogs were attributed primary and positively valenced emotion with more strength and frequency than other groups. Mesocephalic images were also attributed negatively valenced emotions less frequently and with less strength than other groups. Apart from empathy, no significant differences were found in emotional attribution to owned dogs of different head shapes; however, human personality influenced attribution of emotions to owned dogs. The finding that some dogs are attributed emotions more readily based on their appearance alone has applied importance, given, for example, the potential for misattribution of positive emotions to dogs in negative emotional states, and potential prejudice against dogs considered in negative emotional states.
Since its inception, occupational science has explored the phenomenon of humans doing together, including humans doing with other humans and with objects. However, it has yet to explore humans doing with animals. Given animals are living, sentient beings that have the potential to greatly impact human occupation, they cannot be equated to inanimate objects or simply viewed as part of the environment or context. The purpose of this article is to establish the relevance of human-animal interaction to occupational science and open a new line of inquiry and understanding of human-animal occupation. The paper provides background information about human-animal interaction and introduces the impact of canines on occupational engagement, habits, routines, and sense of place. An insight into how human-canine interaction may be reconceptualized as human-animal co-occupation is also presented. Finally, implications for the discipline are discussed. Given that this is a novel topic within the discipline, this paper introduces just some of the ways canines impact occupation.
Despite an enormous quantity of data, contemporary neuroscience does not provide satisfactory explanations for the nature of mind or consciousness. Today the main searches for answers to these questions focus around the problem of the neural bases of consciousness. This article analyzes the most important characteristics of consciousness and the requirements to be met by any fundamental scientific theory explaining it. These criteria are used to critique the most widely discussed neuroscience theories of consciousness. Among them are some satisfying some of the key requirements, though none meets all. I propose that a neuroscientific understanding of consciousness requires us to start thinking of the brain not as a connectome, i.e., a neural network, but as a neural hypernetwork consisting of neuronal groups with specific cognitive properties. The structure of the cognitome is the same as the structure of mind, while consciousness is a specific process of large-scale integration of cognitive elements in this neural hypernetwork.
Cats, along with dogs, are one of the most popular companion animals for humans. Across the world, increasing numbers of cats are being kept as pets. Despite their familiarity, cats’ cognition has long been shrouded in mystery, mainly because cats were considered largely unsuitable for psychological studies in laboratory settings. The “Cats Team” in Kazuo Fujita’s lab has developed several innovative and useful methods for studying cat cognition. In this chapter, I review findings from some of the team’s studies of cat cognition, including physical inference, use human social cues, incidental memory, cross-modal integration, jealousy, and third-party social evaluation. I also briefly describe some ongoing work on the relation between genes and personality, and suggest directions in which behavioral and cognitive studies of cats might go.
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We have limited knowledge on how dogs perceive humans and their actions. Various researchers investigated how they process human facial expressions, but their brain responses to complex social scenarios remain unclear. While undergoing fMRI, we exposed pet dogs to videos showing positive social and neutral non-social interactions between their caregivers and another conspecific. Our main interest was how the dogs responded to their caregivers (compared to a stranger) engaging in a pleasant interaction with another dog that could be seen as social rival. We hypothesized that the dogs would show activation increases in limbic areas such as the amygdala, hypothalamus and insula, and likely show higher attention and arousal during the positive caregiver-dog interaction. When contrasting the social with the non-social interaction, we found increased activations in the left amygdala and the insular cortex. Crucially, the dogs’ hypothalamus showed strongest activation when the caregiver engaged in a positive social interaction. These findings indicate that dogs are sensitive to social affective human-dog interactions, and likely show higher valence attribution and arousal in a situation possibly perceived as a potential threat to their caregiver bonds. Our study provides a first window into the neural correlates of social and emotional processing in dogs.
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A defining characteristic of primary emotions is that they occur in wide variety of species. Secondary emotions are thought to be restricted to humans and other primates. We report evidence from two studies investigating claims of primary and secondary emotions in non-primate species. Study 1. We surveyed 907 owners about emotions that they had observed in their animal. Participants reported primary emotions more frequently than secondary emotions and self-conscious emotions more frequently than self-conscious evaluative emotions. Jealousy was reported at very high levels (81% of dogs and 79% of horses), which was surprising as jealousy is generally defined as a secondary emotion. Study 2. Forty dog owners were interviewed about the contexts and behaviours that led them to claim their animal was jealous. There was coherence and consistency in the behavioural descriptions of jealousy. We claim that such reports provide evidence for the existence of secondary emotions in non-primate species as predicted by theorists such as Buck (19997. Buck , R. 1999 . The biology of affects: A typology . Psychological Review , 106 : 301 – 336 . [CrossRef], [PubMed], [Web of Science ®], [CSA]View all references).
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Attachment as a Monotropic or Polytropic SystemEmotional DevelopmentMeaning of BehaviorProtest over LossReferences
Through a compilation of original articles, the Handbook of Jealousy offers an integrated portrait of the emerging areas of research into the nature of jealousy and a forum for discussing the implications of the findings for theories of emotional and socio-cognitive development. Presents the most recent findings and theories on jealousy across a range of contexts and age-stages of development. Includes 23 original articles with empirical findings and detailed commentaries by leading experts in the field. Serves as a valuable resource for professionals in the fields of clinical psychology, psychiatry, and social work, as well as scholars in the fields of psychology, family studies, sociology, and anthropology.
To characterize infant reactions to jealousy evocation, 94 6-month-olds and their mothers were videotaped in an episode where the mothers directed positive attention toward a lifelike doll, and in 2 contrasting interactions: face-to-face play and a still-face perturbation. Cross-context comparisons of affects and behaviors revealed that jealousy evocation responses were distinguished by diminished joy and heightened anger and intensity of negative emotionality, comparable to levels displayed during the still-face episode; heightened sadness, with durations exceeding those displayed during still-face exposure; and an approach response consisting of interest, looks at mother, and diminished distancing, which was more pronounced than that demonstrated during play. Infants' heightened anger and sadness during jealousy evocation correlated with heightened maternal sensitivity and dyadic vocal turn-taking, respectively, during play; and infants' diminished joy and interest during jealousy evocation were associated with heightened maternal withdrawal and intrusiveness, respectively, during play. Both fear and mother-directed gaze were greater in girls. The discussion argues for interpreting the infant's mixed and agitated reaction to jealousy evocation as evidence of jealousy.
Thirty-two 6-month-old infants were exposed to their mothers attending, in turn, to a lifelike baby doll and a book. Infant negativity was greater when maternal attention was directed toward the social object, suggesting the presence of an early form of jealousy by 6 months of age.
Providing an important advance, this groundbreaking volume is the first to offer a comprehensive review of modern research on romantic jealousy. It offers a conceptual framework for ordering past research, an up-to-date review of the literature from diverse sources and fields, and useful clinical strategies for practitioners and clinicians in training. This volume concentrates on romantic jealousy, which the authors define as neither an emotion, a state of mind, nor a way of behaving, but rather as a multisystem phenomenon involving personality, relationships, culture, and perhaps biology. The book opens by presenting a model of romantic jealousy that integrates research and clinical phenomena. It then offers analyses of several different perspectives including: sociobiological and personality approaches; ways in which relationship characteristics and dynamics contribute to jealousy; gender differences; and cultural and social factors that affect jealousy. Chapters on clinical concerns focus on violence, psychopathology, and the assessment and treatment of normal, reactive, and symptomatic jealousies. Specific strategies are provided with clinical, real-life, and cross-cultural case examples used throughout. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
IntroductionThe Development of Social EmotionsWhat is “Complex” about Complex Emotions?The Case of JealousyIdentifying with OthersThe Case of AutismConclusion References
Twelve-month old infants (N = 76) experienced 4 situations of unresponsiveness in which their mothers and a stranger directed positive attention toward a doll or a picture book while they ignored the infant. Infants demonstrated more protest, negative vocalizations and inhibited play during the doll condition, particularly if the doll was held by the mother. Infant contacts with the mother were more frequent when the mother held the doll. Infants’ distress during the mother/doll condition was interpreted as jealousy.