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Man’s other best friend: domestic cats (F. silvestris catus) and their discrimination of human emotion cues

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The ability of domestic dogs (C. lupus famaliaris) to follow and attend to human emotion expressions is well documented. It is unknown whether domestic cats (F. silvestris catus) possess similar abilities. Because cats belong to the same order (Carnivora), but did not evolve to live in complex social groups, research with them enables us to tease apart the influence of social structure versus domestication processes on the capacity to recognize human communicative cues, such as emotions. Two experiments were conducted to determine the extent to which domestic cats discriminate between human emotion cues. The first experiment presented cats with facial and postural cues of happiness and anger from both an unfamiliar experimenter and their familiar owner in the absence of vocal cues. The second experiment presented cats with vocal cues of human emotion through a positively or negatively charged conversation between an experimenter and owner. Domestic cats were only modestly sensitive to emotion, particularly when displayed by their owner, suggesting that a history of human interaction alone may not be sufficient to shape such abilities in domestic cats.
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ORIGINAL PAPER
Man’s other best friend: domestic cats (F. silvestris catus)
and their discrimination of human emotion cues
Moriah Galvan
1
Jennifer Vonk
1
Received: 24 April 2015 / Revised: 20 August 2015 / Accepted: 15 September 2015
Ó Springer-Verlag Berlin Heidelberg 2015
Abstract The ability of domestic dogs (C. lupus fama-
liaris) to follow and attend to huma n emotion expressions
is well documented. It is unknown whether domestic cats
(F. silvestris catus) possess similar abilities. Because cats
belong to the same order (Carnivora), but did not evolve to
live in complex social groups, research with them enables
us to tease apart the influence of social structure versus
domestication processes on the capacity to recognize
human communicative cues, such as emotions. Two
experiments were conducted to determine the extent to
which domestic cats discriminate between human emotion
cues. The first experiment presented cats with facial and
postural cues of happiness and anger from both an unfa-
miliar experimenter and their familiar owner in the absence
of vocal cues. The second experiment presented cats with
vocal cues of human emotion through a positively or
negatively charged conversation between an exper imenter
and owner. Domestic cats were only modestly sensitive to
emotion, particularly when displayed by their owner, sug-
gesting that a history of human interaction alone may not
be sufficient to shape such abilities in domestic cats.
Keywords Domestic cats Human emotion
Communicative cues Companion animal
Introduction
It is surprising to find that achieving the status of the
world’s most popular pet (Bernstein 2007; The Humane
Society of the United States 2011) does not assure you a
seat at the main table in the current comparative scientific
discussion. Despite the recent explosion of canine cogni-
tive research and canine–human interaction studies (re-
viewed in Miklo
´
si and Topa
´
l 2012; Ude ll and Wynne
2008), cats have yet to be a large part of the recent trend
toward attempting to understand the cognitive abilities of
domestic pets (for a recent review, see Vitale Shreve and
Udell 2015). Understanding the cat–human relationship has
the potential to challenge popular beliefs that sociality and
coevolutionary processes are necessary conditions for the
ability of companion animal s to understand cues of human
emotions. Although cats do not have the same domestica-
tion history as dogs, they have an evidenced bond with
humans (Edwards et al. 2007; Zasloff 1996; Za sloff and
Kidd 1994) that may be well served by an understanding of
human communicative cues.
Although cats and dogs have different social histories,
their early beginnings with humans are similar. Time lines
for both species vary, but estimates indicate that the first
domesticated dog dates back to 14,000–33,000 years ago
(Druzhkova et al. 2013; Ovodov et al. 2011). Cat domes-
tication may have taken place as far back as 10,000 years
ago in the Fertile Crescent of the Middle East (Driscoll
et al. 2007). By comparing the two species, both wild cats
and wolves self-domesticated to early human settlements
(Driscoll et al. 2009; Fogle 2007). Wolves were immedi-
ately useful to humans as alarm systems, hunters, and
companions (Mull er 2002), and they were subsequently
selectively bred for tameness, obedience, and continued
working service (Trut 1999), whereas wild cats found no
& Jennifer Vonk
vonk@oakland.edu
1
Department of Psychology, Oakland University,
2200 N Squirrel Rd., Rochester, MI 48309, USA
123
Anim Cogn
DOI 10.1007/s10071-015-0927-4
such niche. It is likely that humans tolerated wildcats for
their pest-controlling abilities, but had little use for them
otherwise. Additionally, a ‘tamer, more obedient cat’ was
difficult to breed given that wild cats easily escaped human
confines and reproduced freely outs ide of human estab-
lishments. Thus, the domestication process for cats took
thousands of years longer than for dogs (Driscoll et al.
2009).
The two-s tage hypothesis (Udell et al. 2010) proposes
two critical elements necessary for a domesticated animal
to sensitize to human cues: First, the nonhuman animal
must be willing to accept humans as companions, a process
that usually occurs during early ontogeny. Second, the
animal should learn through conditioning to follow human
actions in order to receive reinforcement. The sensitive
period of socialization for kittens occurs from 2 to 7 weeks
of age. If socially engaged during this period, kittens have
the ability to imprint and recognize specific human han-
dlers, which supports the idea that cats accept humans as
social companions (Karsh 1983; Karsh and Turner 1988).
Kittens socialized to humans during the sensitive period
display less fearful responses to humans at later ages and
become more social toward humans overall (Casey and
Bradshaw 2008; Karsh and Turner 1988). Turner (1991)
suggests that humans may even serve as stimula tion for
indoor cats in a mutually rewarding relationship, with each
subject (human or cat) readily complying with the other’s
need for interaction. These findings suggest that increased
levels of kitten socialization with humans lead to an
increased desire for human connection later in adult cat life
(Casey and Bradshaw 2008; Karsh 1983), and thus the
acceptance of humans as social companions.
In support of the second stage of the two-stage
hypothesis, cats also appear capable of learni ng to respond
to some human actions. For example, there is evidence that
cats are as capable as dogs at following basic human ges-
tural cues (Miklo
´
si et al. 2005). Miklo
´
si et al. (2005) tested
cat and dog subjects on four different types of human-
presented communicative cues in the form of pointing
gestures. The gestures were combinations of proximal
(10–20 cm away from the bowl) or distal (70–80 cm away
from the bowl) cues and momentary (the point position was
held for 1 s and then removed) or dynamic (the point
position was held for the duration of the trial until the
subject made his/her choice) cues. If the animal understood
the cue, it could utilize the cue to locate hidden food in one
of two containers. The results indicated that cats were as
proficient as dogs in their use of the four types of com-
municative cues, although the authors suggested that dogs
may have the overall advantage in following communica-
tive gestures due to their trainability and tendency to offer
extended visual contact with humans. Notable, however, is
that neither species demonstrated significant learning
throughout the duration of the experiment, sugges ting that
both species were familiar with communicative cues and
their potential meanings before the onset of the experiment.
An ability to respond to human points need not imply
anything about the underlying representation of a human’s
intentions, but it does imply that cats are able to use these
cues to predict the presence of objects of interest.
The goal of the current study was to extend these find-
ings to the domain of human emotion cues. As with the
ability to follow gestural cues, an ability to respond dif-
ferently or appropriately to varied cues of human emotion
need not imply that cats have representations of the
meaning of underlying emotion states, but it would again
show that cats are able to interpret and predict different
consequences based on cues provided by humans. In this
case, cues provided by emotion expressions might be
considered to be more subtle than overt point and gesture
cues. Therefore, an ability to use human emotions as pre-
dictive cues to likely outcomes is unlikely to emerge in the
absence of prolonged human contact, but we also ques-
tioned whether it would depend upon having evolved to
live in social groups, in which case, dogs, but not cats,
should have this ability. Domestic dogs have previously
demonstrated the ability to differentiate human facial
expressions. For example, Deputte and Doll (2011) found
that dogs displayed more avoidant behavior and were sig-
nificantly less likely to approach actors displaying angry
expressions in comparison with actors displaying happy
expressions. Buttelmann and Tomasello (2013) determined
that dogs were able to utilize human facial expressions of
happiness and disgust to locate hidden food. Merola et al.
(2012) found that dogs did not regulate their behavior as a
function of positive or negative emotional messages pro-
vided by humans in a social referencing paradigm, but did
respond different ly toward a potentially frightening object.
Furthermore, a follow-up study found that dogs were better
able to distinguish between emotions when their familiar
owner, rather than a stranger, presented the cues (Merola
et al. 2014). In this study, dogs could distinguish between
their owners’ fearful and happy expressions and use these
cues to guide their explorations of boxes, but, as in But-
telmann and Tomasello (2013), had more difficulty dif-
ferentiating neutral expressions from other emotional
expressions. These findings support the idea that dogs
interpret human emo tion expressions in an adaptive man-
ner allowing them to predict plausible outcomes, but that
specific experience through human interaction is critical.
Merola et al. (2015) also recently tested domestic cats in
a similar social referencing paradigm and found similar
rates of looking between the owner and the ambiguous
object as they previously observed in dogs (2012). This
result contrasted with a previous study that reported lower
rates of gaze to the owner from cats compared to dogs
Anim Cogn
123
(Miklo
´
si et al. 2005) when food was placed out of reach.
Furthermore, Merola et al. (2015) found only subtle
behavioral differences whe n the owner reacted in negative
versus positive ways to an ambiguous object (i.e., a fan).
For exam ple, cats were slightly quicker to start moving in
the negative condition and gazed more at a possible exit.
Thus, previous studies have suggested the possibility that
cats will show more subtle effects of human emotion cues
compared to dogs, but with only one existing study testing
cats (Merola et al. 2015) it is important to examine cats’
behavior in different contexts.
In the current study, we measured domestic cats’ natural
responses to humans exhibiting different emotion states in
two experiments using facial, postural, (Experiment 1) and
vocal (Experiment 2) cues of emotion. We hypothesized
that cats with a close personal relat ionship to humans
would alter their behavior in accordance with two basic
human emotions: happiness and anger. In accord ance with
previous research finding that dogs (Merola et al. 2014) and
cats (Collard 1967; Casey and Bradshaw 2008; Edwards
et al. 2007) respond differently to familiar vers us unfa-
miliar humans, we also manipulated familiarity of the
human with the prediction that cats may be better able to
differentiate the emotions of a familiar human caretaker
compared to a stranger. The first experiment tested cats in a
very familiar room of their home with a familiar and
unfamiliar human using only emotion-related facial
expressions and posture for the emotions of happiness and
anger. The second experiment tested cats in a neutral lab-
oratory with both their familiar owner and an unfamiliar
experimenter using positive and negative emotional vocal
cues (in the form of an emotionally charged conversation)
to inve stigate their reac tivity to an auditory cue of emotion
versus a visual cue alone. In both experiments, we
observed the cats’ behavior and disposition, their latency to
approach the (unfamiliar) experimenter or their (familiar)
owner, and the duration in which they stayed in close
proximity to either human. Additionally, in the second
experiment, we added the variable of gaze direction and
duration of gaze.
Experiment 1
In Experiment 1, we sought to determine whether cats
would behave differently in response to two basic human
emotion expressions without the use of verbal or dynamic
movement cues. The two human expressions simulated for
the cats were happiness (positive ) and anger (negative, see
Fig. 1). We predicted that cats would respond more posi-
tively, approach the human more quickly, and spend more
time in contact with the human in the positive emotion
condition compared to the negative emotion condition. We
also expected that these effects might be more pronounced
for the familiar owner, and that cats would generally
approach the familiar owner faster than the unfamiliar
experimenter. In contrast to the previously reviewed
research, we were not interested in the ability of the cats to
infer a communicative message with regard to a secondary
object. Rather, we wished to measure a natural response to
an indicator of emotional state, which might predict a
direct behavioral consequence for the subject (i.e., an angry
person is more likely to cause harm relative to a happy
person). By reducing the extent to which the cat had to
infer a goal or disposition on the part of the human towar d
an external object, we hoped to increase the potential to
observe differential effects of the cats’ behavior with
regard to the human’s differing emotion cues.
Method
Subjects
Experiment 1 included 12 sterilized adult cats from five
different households. Eight of the cats had participated in a
pilot study, which was similar to the current study but
involved releasing the cats from crates, and four of the cats
Fig. 1 Experimental setup for Experiment 1
Anim Cogn
123
were naı
¨
ve to testing. Five different owners participated in
this experiment. All of the cats were of mixed breed (seven
males, five females) and ranged in age from an estimated
1–12 years. All were housed indoors and were ‘rescued’
from shelters or as strays. All were described as affec-
tionate with their owners.
Materials
Experiment 1 required two video cameras on tripods, a
stopwatch, a measuring tape and placeholders, and a small
food dish with treats. The video camera s on tripods were
set in different places according to the testing room.
However, each room had a video camera capturing the
main footage of the session (the area in close proximity to
the human, including the treat bowl and starting location of
the cat), as well as a background video camera to capture
areas not accessible by the main video where the cat may
have investigated during the experiment.
Testing environment
The cats had a room in their house where they spent the
majority of their time. These rooms were used as the
testing spaces for the experiment. They were all approxi-
mately equivalent in size (*4 9 4 m) with at least one
window and a door to keep subjects in the testing space
during testing. All items (cat furniture, human furniture,
toys, water bowls, etc.) were left in the testing space to
maintain the normalcy of each room, but each room con-
tained enough empty space to make it possible to conduct
the experiment. The basic setup is depicted in Fig. 1.
Procedure
Eight of the cats participated in eight trials (two individual
trials per day) across four test days. Given observed con-
sistency in behavior over time and based on the availability
of the additional three owners, the remaining four cats
participated in four trials (one of each condition) in one test
day. The order of presentation of emotion expressions was
counterbalanced across and between cats, such that every
cat participated in four happy emotion expression trials and
four angry emotion expression trials (two of each with the
familiar owner and unfamiliar experimenter), but no cat
received the same order of presentation of expressions.
Although the unfamiliar experimenter was no longer
completely unfamiliar give n that she had participated in
four trials with eight of the cats in the pilot, she was still
unfamiliar in comparison with the familiar owner (with
whom each cat had lived for several years). Thus, there
were four test conditions for Experiment 1: familiar happy,
unfamiliar happy, familiar angry, and unfamiliar angry.
Facial expressions were based on Ekman and Friesen
(1975). Each was presented while the experimenter was
sitting cross-legge d, in direct sight line with the subject.
The facial expressions were based on descriptions and
images of human facial expression and emotion given by
Ekman and Friesen (1975) and are depicted in Fig. 2. The
experimenter had amateur theatrical experience, but to
ensure that she was exhibiting the appropriate facial
expressions for the designated trials, a naı
¨
ve coder verified
the intended emotion on 96 % (70/73) of the trials by
observing the trials on video.
Angry emotion expression In the angry emotion expres-
sion condition, the experimenter sat cross-legged, with
arms tense and hands clenched in fists resting on her/his
knees. Posture was upright, tense, and slightly leaning
forward. The face was clenched, with eyebrows furrowed
and pinched toge ther. The mouth was firmly set, lips
puckered in, with chin slightly protruding. As with the
Fig. 2 Facial expressions for Experiment 1: angry (top) and happy
(bottom)
Anim Cogn
123
happy condition, direct gaze was given to the subject for
the duration of the trial.
Happy emotion expression In this condition, the experi-
menter sat cross-legged, with arms resting loosely on her
knees or in her lap. Posture was upri ght, but relaxed. The
face was relaxed, eyes slightly narrowed, with soft gaze
directed toward the subject for the duration of trial. The
experimenter was smiling (which alternated during a trial
between showing teeth or not to prevent strain) and
maintained relaxed breathing.
On each test day, the experimenter (female, 23 years)
arrived at the home of the cats with all necessary materials.
She wore neutral clothing. She went directly to the room
that the owner indicated the cat should be tested in and set
up the equipment. In each testing room, the measurements
were identical. The experimenter marked .5 m from the
entrance into each testing room as the location for the
experimenter to sit. The treat bowl was marked 2 m from
the experimenter’s location, toward the center of the room.
The treat bowl was used as motivation to lure the cats into
a consistent starting position 2 m away from the experi-
menter (unfamiliar or familiar). When first placed, this
worked to reposition the cats from the door to the room to
the start position, allowing the experimenter to enter.
On each trial, the owner turned on the video cameras,
placed several tre ats into the bowl, and placed the cat in
front of the bowl before exiting the room. If the cat
approached the bowl and immediately began eating, the
owner indicated to the experimenter to enter the room, sit,
and begin the trial by displaying the emotion expression.
When the experimenter was in position, the owner shut the
door and started the stopwatch. The trial las ted 3 min. If
the cat did not approach the treats immediately after they
had been set down, the owner would exit the room, start the
stopwatch for 1 min, and then indicate to the experimenter
to enter the room and begin the trial as described previ-
ously. At the end of 3 min, the owner would knock on the
door, indicating the end of the trial. This signaled to the
experimenter to stop the video cameras, open the door, and
release the cat back into the main living area. These roles
were reversed if the owner was participating in the trial
(familiar condition). The order in which the cats were
tested was randomly determined across all test days. In the
multi-cat house, all of the cats rotated through their first
trial before beginning the second trial. This allowed for
maximal time between trials for each cat in an attem pt to
counteract any possible habituation effects.
Behavior coding All behavioral data were coded from
video by a naı
¨
ve research assistant. Additionally, a second
research assistant coded a random 25 % of the videos for
reliability. The research assistants yielded a high inter-rater
correlation for latency to exit the carrier (r = 1.00,
p = .01), behaviors presented (r = .93, p = .01), and
duration of time spent in contact with either human
(r = .98, p = .01). The assistants measured approach
latency, duration of contact, and types of behaviors pre-
sented by the cat (grouped as positive, negative, or neutral
behaviors).
Dependent Measures Approach latency was measured as
the time it took from the start of the trial for the cat to be
within 10 cm of the experimenter’s body. This time was
recorded as the time to ‘make contact.’ The duration of
time spent in contact with either type of human was the
sum of the time(s) the cat spent ‘making contact with a
human. ‘Making contact’ included behaviors such as
rubbing against the exper imenter, eating the treats, sniffing
the experimenter within 10 cm of the experimenter’s body,
pawing at the experimenter, climbing in her lap, and other
curiosity/attention-seeking behaviors.
Cat behavi or(s) The behavioral ethogram depicted in the
section Appendix was utilized to ensure that the research
assistant could accurately gauge cat behavior and body
language. The ethogram was based upon earlier work by
Leyhausen (1979) with some modifications to suit the
current research. The assistant was asked to watch each
video in 15-s blocks (demarcated with a stopwatch) and
indicate all behaviors observed at each interval using
interval sampling. That is, they simply checked a box
whether a behavior was present during that 15-s interval.
After coding was completed, the behaviors were catego-
rized as those that were explicitly positive and negative.
For example, having ears forward and normal, relaxed
body posture were considered positive behaviors, whereas
slinking, tense body posture and a tightly tucked tail were
considered negative behaviors. The frequencies of each
type of behavior were summed.
Data analysis
Data (approach latenc y, duration of contact, and positive/
negative behavior frequencies) were analyzed using repe-
ated measures ANOVAs with familiarity (familiar , unfa-
miliar) and emotion (happy, angry) as repeated factors,
using SPSS version 20.0. We used simple main effect tests
(paired t tests) to examine significant interactions. We
applied a Bonferroni correction for multiple analyses
(.05/3) accepting a p value as significant at .017.
Results
A repeated measures ANOVA on appro ach latency with
familiarity (familiar owner, unfamiliar exper imenter) and
Anim Cogn
123
emotion (happy, angry) as factors revealed no significant
differences in approach latency based on emotion
(F
1,11
= .00, p = .96, g
2
= .00) or familiarity
(F
1,11
= .06, p = .81, g
2
= .01). There was no interaction
of emotion and familiarity (F
1,11
= 2.10, p = .18,
g
2
= .16). Figure 3 shows the results for total duration of
contact. There was no main effect of emotion (F
1,11
= .75,
p = .41, g
2
= .06) or familiarity (F
1,11
= 3.67, p = .08,
g
2
= .25), but there was an interaction between emotion
and familiarity that approached our adjusted sign ificance
level (F
1,11
= 9.98, p = .01, g
2
= .48). To probe the
interaction, simple effect tests were conducted in the form
of paired sample t tests to compare duration of contact in
happy versus angry conditions for familiar owners and then
for unfamiliar experimenters. The test was not significant
for the unfamiliar experimenter; t
11
=-.98, p = .35, CI
-35.94–13.84. For the familiar owners, there was a ten-
dency for cats to spend more time in contact with their
owner in the happy (M = 66.75, SD = 63.11) versus angry
condition (M = 34.21, SD = 38.69), t
11
= 1.96, p = .08,
CI -4.08–69.17). The results are depicted in Fig. 3.
Figure 4 shows the results for (a) positive and (b) neg-
ative behaviors. The behaviors were averaged across trials
and were also analyzed using a repeated measures ANOVA
including the factors of emotion and familiarity, as well as
valence (positive, negative). There were significantly more
positive behaviors exhibited by the cats than negative
behaviors (F
1,11
= 29.03, p \ .0 01, g
2
= .73). There was a
significant three-way interaction between valence of
behaviors, emotion, and familiarity (F
1,11
= 10.69,
p = .01, g
2
= .85). The interaction was probed using
separate repeated measures ANOVAs, split on the factor of
valence (positive and negative). There was a significant
interaction between emotion and familiarity only for pos-
itive behaviors (F
1,11
= 10.37, p = .008, g
2
= .49). To
examine the interaction, two paired samples t tests were
conducted, one for familiar owner and another for the
unfamiliar experimenter. For the experimenter, emotion
was not significant, t
11
=-1.44, p = .18. For the owner,
however, emotion approached significance, t
11
= 2.76,
p = .02. The cats displayed more positive behavior
when their owner was displaying a happy (M = 24.42,
SD = 14.08), rather than an angry, expression (M = 14.08,
SD = 12.83).
Discussion
Although the cats did not appear to alter their approach to
their owner based on the emotion condition, they did alter
their overall behavior by responding more positively to
their owner in the happy condition. With regard to the
duration of time the cats spent in contact with either type of
human, the cats spent more time with their owner in the
happy than in the angry condition, whereas they showed no
significant difference with the unfamiliar experimenter.
Thus, these cats were more sensitive to emotions when
displayed by the owner—being more likely to engage in
Fig. 3 Average time spent in contact with either human (familiar or
unfamiliar) in both emotion conditions (happy or angry) in Exper-
iment 1
Fig. 4 a (top) Depicts the significant interaction between emotion
and familiarity for positive behaviors in Experiment 1. b (bottom)
Depicts the nonsignificant interaction between emotion and familiar-
ity for negative behaviors in Experiment 1. Note the figures are
presented on different scales for the sake of clarity
Anim Cogn
123
positive behaviors and spend time in contact with her when
she appeared to be happy than when she appeared angry.
These findings are consistent with findings that dogs find it
easier to discriminat e familiar emotions with familiar
humans (Merola et al. 2014). It should be noted that rela-
tively subtle change s in cats’ behavior as the result of
emotional cues given by familiar humans are also consis-
tent with previous research (Merola et al. 2015). Taken
together, these findings at least suggest that cats prefer
positive emotion states in humans when these emotion
states are conveyed by familiar humans with which they
have established social bonds. We had deliberately con-
trolled for sensitivity to auditory cues of emotion in the first
experiment, but, given the relatively subtle effects with
only visual cues present, we decided to include vocal cues
in a follow-up experiment.
Experiment 2
In this experiment, we presented cats with vocal cues, in
the form of an emotionally charged conversation (positive
or negative) to increase the saliency of the cue and
potentially the likelihood of the cats differentiating the two
conditions. Vocal cues were selected given cats’ sensitivity
to auditory information (Fay 1988; Warfield 1973) and
recent research by Saito and Shinozuka ( 2013) that
demonstrated that cats differentiate and respond more to
the voice of their owners than to the voices of novel
humans. Cats were transpor ted to a novel researc h site for
this experiment; thus, carriers were introduced to both
(a) protect the cats durin g travel and (b) provide a con-
sistent starting position for both trials. If the cats could
discriminate the vocal emotion cues, we expected that they
should alter their latency to exit their carrier such that they
would be more hesitant to leave the carrier during the
negative emotion condition and faster to exit the carrier in
the positive emotion condition. Additionally, the cat’s
overall disposition during the trial should reflect the con-
dition, i.e., an increase in negative behaviors in the nega-
tive condition and an increase in positive behaviors in the
positive condition. We also expected cats to spend more
time in contact with the owner and experimenter during the
positive condition, and we thought that this effect might be
even more pronounced for the experimenter.
In Experiment 2, we also measured frequency of gaze
toward both humans based on a recent finding that cats may
utilize social referencing (Merola et al. 2015), in which an
individual utilizes the perceptions and behaviors of another
to shape their understanding of a situation (Feinman 1982).
Given that the cats were placed in a novel environment in
Experiment 2 and could use the owner as a reference when
approaching the unfamiliar experimenter, gaze was a more
useful cue here than in Experiment 1 where there was only
one human present in a familiar environment. Social ref-
erencing is a know n phenomenon in dogs (Merola et al.
2012, 2014), whereby dogs will alter their ‘looking’
behavior and locomoti on toward a novel object based on
their owner’s reaction. More than 80 % of the dogs in
Merola et al.’s (2012) study looked referentially toward
their owner. Additionally, they altered their behavioral
approach and avoidance of the novel object based on their
owner’s own negative-avoidance response. The same
research team recently found cats capable of social refer-
encing under the same conditions (Merola et al. 2015).
Therefore, in this study, it was hypothesized that the cats
might spend more time exploring the room (perhaps closer
to the experimenter) during the positive condition, whereas
they might gaze more frequent ly at their owner in the
negative condition when the atmosphere would be tense.
The hypothesis of Experiment 2 was that understanding the
cues of positive human emotion would signal relaxation to
the cats, whereas understanding the cues of negative human
emotion would signal fear and hesi tancy to engage in
contact with the cats.
Method
Subjects
Experiment 2 included 26 sterilized adult cats (15 males,
11 females). Twenty-three of the 26 cats lived exclusively
indoors at the time of testing, two cats lived primarily
indoors but had access to the outdoors, and one cat lived
exclusively outdoors. The cats came from 16 households;
therefore, 16 owners participated in the experiment. The
average age of the cats was 5.53 years, with the average
age of adoption as 1.19 years. On average, the cats had
cohabitated with their current owner for 3.93 years before
participating in this experiment. Before being adopted, 11
of the cats were identified as strays, six were adopted from
shelters with unknown prior histories, five were house cats
for the duration of their lives, two were exclusively outdoor
cats, and one was a farm cat. None of the cats were con-
sidered feral, indicating that all of them had received some
early socialization with humans such that they accepted
and were responsive to the presence of humans. The cats
were solicited via social media (Facebook), on campus
recruitment (handing out flyers in psychology classes), and
word of mouth. To participate, cats had to be physically
healthy and easy to handle. The owner was required to
bring the cat in a travel carrier, with the ability to replace
the cat in the carrier several times throughout the duration
of the experiment. The owne rs were given a five-dollar gift
card for participation, with intended use for supplies for
their cat.
Anim Cogn
123
Materials
The laboratory room was equipped with two video cameras
on tripods, a table for the cat and carrier, place markers for
the humans to stand on, and a stopwatch for timing the
trials. The owner completed informed consent forms and
demographic surveys before the trial began.
Testing environment
The laboratory space was rectang ular (3 9 4 m), with one
door and two windows. The laboratory and windows were
painted black. The room held minimal distractions for the
cats. Before testing began, the laboratory room was con-
figured for testing. A 2 9 1 9 .5 m table was placed
lengthwise in the room. The video cameras were positioned
to allow maximal video footage of the room. One video
camera and tripod was erected facing the table where the
carrier was placed with the front of the carrier facing the
camera. This camera captured the cat’s behavior and gaze
as he/she remained in, or exited, the carrier. The second
video camera and tripod was placed in the corner of the
room, behind the table and carrier. This camera captured
the cat’s movements around the room after he/she exited
the carr ier. Place markers in the form of a masking tape
‘1’ and ‘2’ were placed on the ground .5 m from the end
of the table where the cat carrier faced. The place markers
allowed the experimenter to counterbalance the owner’s
position to eliminate any side biases the cat may have had.
This meant for one trial, the owner stood on the number
‘1’ and the experimenter on the number ‘2,’ while in the
other trial the owner stood on the number ‘2’ and the
experimenter stood on the number ‘1.’ See Fig. 5 for a
diagram of the laboratory setup.
Procedure
The cat was brough t to the testing facility in a travel carrier
and escorted to the laboratory space by the experimenter.
Upon reaching the laboratory, the experimenter instructed
the owner to place the carrie r on the table with the carrier
front facing the video camera. She then asked the owner to
step into the hallway to allow the cat to accli mate to the
testing space as well as to explain the trial procedure. The
owner was instructed that the experimenter would be having
two conversations with him/her. This procedure required
acting on the part of the research team and the owners of the
cats. The experimenter had amateur theatrical experience,
but the owners were not known to. For this reason, the
experimenter provided scripted phrases that served as
emotion prompts for both the owners and the experimenter to
use to convincingly convey the emotion in front of the cat.
The owner was told that he/she was free to use the scripted
prompts or to ad lib the conversation as long as the content
maintained the emotion of the trial. The experimenter indi-
cated that during the conversations, the owner was to keep a
moderate and consistent vocal volume (no yelling or making
loud noises that could startle the cat), to avoid touching or
making eye contact with his/her cat should he/she approach,
and to avoid exces sive movement (e.g., waving arms,
shaking a fist, or other movements that may frighten the cat).
When the owner understood the procedure, the owner and
experimenter equipped with a stopwatch to time the trial
entered the laboratory. Exact movements and scripts were
not controlled or standardized because the goal was to
establish a natural conversation that varied in emotional
tone, and corresponding expression and postures. In order to
verify that the conversations were interpreted as positive and
negative to a naı
¨
ve human observer, a research assistant who
was naı
¨
ve to the purpose of the study coded the emotional
valence of the trials from video. Her coding agreed with the
intended valence on 100 % of the trials.
Each cat participated in two consecutive 2-min trials.
Upon entering the laboratory, the experimenter initiated
recording on both video cameras. The experimenter then
asked the owner to open the cat carrier door and then stand
Fig. 5 Experimental setup for Experiment 2
Anim Cogn
123
facing the experimenter, on the number ‘1’ or ‘2’ taped
on the floor. Position was counterbalanced across individ-
ual cats and across conditions. The trial started when the
cat carrier door was open and the owner was standing on
the appropriate positional number facing the experimenter.
The experimenter started the stopwatch and engaged the
owner in conver sation with the appropriate emotional tone
for that trial. One trial was deemed positive and the other
negative with order of presentation randomized across cats.
When 2 min had elapsed on the stopwatch, the experi-
menter asked the owner to place the cat back in the carrier
and secure the carrier door. While the owner collected the
cat, the exper imenter turned off the video cameras and then
both humans exited the room to prepare for the next trial. To
avoid the cat becoming familiar with the experimenter dur-
ing the first trial and therefore exiting the carrier faster on the
second trial, a research assistant (also female, though with-
out theatrical experience) performed the second trial with the
owner, following the same procedure as the first trial.
Behavior coding We measured the duration that each
subject spent in proximity to the owner and experimenter/
research assistant (measured by dividing the video screen
into four equal quadrants), the cat’s gaze direction during
the trials (at the experimenter or owner), the latency to exit
carrier and overall behavioral disposition (varying from
stressed to relaxed) for each trial. Two research assistants
who were naı
¨
ve to the hypotheses of the study coded the
video to assess these variables. They were instructed to
keep the sound of videos muted to avoid any coding biases.
The research assistants yielded a high inter-rater correla-
tion for latency to exit the carrier (r = .90, p = .03) and
for behavioral disposition (r = .76, p = .002)
Results
To measure the duration of time in proximity to
owner/experimenter, the video for each trial was divided
into four equal sized quadrants. The amount of time spent
on the side (which was comprised of two adjacent quad-
rants) with the owner was summed, as was the amount of
time spent on the side (comprised of the other two adjacent
quadrants) where the experimenter was positioned. A
repeated measures ANOVA with the factors of emotion
(positive and negative) and familiarity (unfamiliar experi-
menter/research assistant and familiar owner) for the
duration of time spent in proximity to both types of human
was performed. There were no significant main effects of
emotion (F
1,21
= .60, p = .45) or familiarity (F
1,21
=
2.23, p = .15) and no significant interaction (F
1,21
= .001,
p = .98).
Figure 6 summarizes where the cats were focusing their
attention during the trial. A frequency of ‘looks’ toward
the owner, experimenter, or anywhere else in the room was
acquired by tallying where the cats were looking at 10-s
intervals for the duration of the trial. A repeated measures
ANOVA was conducted on gaze frequency with the factors
of emotion (positive and negative) and familiarity (unfa-
miliar experimenter/research assistant and familiar owner).
Emotion did not have a significant impact on gaze fre-
quency (F
1,25
= .72, p = .40). However, the effect of
familiarity approached significance based on our adjusted
p value in that cats looked significantly more at their owner
than at the experimenter (F
1,25
= 4.96, p = .04). There
was no interaction between emotion and familiarity
(F
1,25
= 1.44, p = .24).
The time until the cat exited the carrier in both trials was
measured using a stopwatch. These times, grouped
according to emotion (positive or negative), were com-
pared using a paired samples t test. The results were non-
significant based on emotion condi tion (t
25
= .34,
p = .73).
Lastly, to measure behavioral disposition, the research
assistants were given a behavioral ethogram (see Ap-
pendix section) and asked to rate the cats on a Likert scale
ranging from -2 (very stressed) to 2 (very relaxed) for the
overall trial. A paired samples t test was conducted to
compare the total scores based on condi tion (positive or
negative). There was no significant difference between
perceived emotional state/behavioral disposition based on
emotion condition (t
25
= .42, p = .68).
Discussion
The results from Experiment 2 indicate that the cats do not
adjust proximity to their owner or the experimenter based
Fig. 6 Average frequency of ‘looks’ toward owner (familiar)or
experimenter (unfamiliar) in both the negative and positive emotion
conditions in Experiment 2. There were signi ficantly more ‘looks’
toward the owner than the experimenter
Anim Cogn
123
on emotion condition, nor do they modify their latency to
exit their carrier based on the emotion condition (positive
or negative). Additionally, when a research assistant was
asked to rate the cats on their overall disposition through-
out the trial, it did not appear that the cats were reacting
more negatively (stressed) under the negative emotion
condition, or more positively (relaxed) during the positive
emotion condition. This is unlikely to be due to high levels
of distress from the experimental manipulation given that
the average behavioral disposition scores were positive in
both conditions. Finally, the cats gazed more at their owner
than at the unfamiliar experimenter, suggesting that they
may have been looking for cues, as in social referencing,
from the owner. That the use of the owner as a source of
reference was not differentiated based on emotion cues
suggests that the cues provided were not salient to the cats
and that cats viewed both experimental conditions as
equally ambiguous. Thus, the results from this study may
indicate their propensity for social referenci ng, consistent
with Merola et al. (2015), such that cats look more toward
their owners in novel situations regardless of the emo tional
atmosphere.
There are several reasons why emotional context may
not have significantly impacted proximity to owner/ex-
perimenter, latency to exit carrier, and behavioral dispo-
sition. First, because the experimenters and owners were
acting, the cats may have been unable to hear or feel a
sincerely negative environment in the way they might
perceive negative emotion in their home when their owner
is truly upset. Furthermore, natural emotions may be
associated with different chemical or olfactory signals that
were not present in the contrived experimental conditions.
However, Mayes et al. (2015) have shown that, in a food
search task, cats appear to prioritize visual over olfactory
cues, suggesting that the lack of chemical cues in this
scenario may not have been responsible for preventing
them from discri minating between conditions. Second, the
laboratory setting was exciting to some cats and stressful to
others. Whereas some of the cats eagerly exited their car-
rier to explore (regardless of what their owner and exper-
imenter were doing), others appeared stressed, and their
response to the emotion conditions may have been masked
by their neophobia. Thus, individual differences in
response to the situation may have exerted a stronger
impact on behavior than the exper imental manipulation.
General discussion
These experiments are among the first conducted on
domestic cats to determine their discrimination of human
emotion expressi ons. The results suggest that cats may alter
their behavior in subtle ways based on the expressions of
emotion, especially when a familiar owner is displaying the
emotion, similar to the findings of Merola et al. (2015). For
example, in Experiment 1, cats spent more time in contact
with their familiar owners when those owners appeared
happy than angry. However, unlike domestic dogs and their
extensive, easily quantifiable usage of human emotive cues
(Buttelmann and Tomasello 2013; Deputte and Doll 2011;
Merola et al. 2012, 2014; Muller et al. 2015), cats do not
appear to display the same type of responses when pre-
sented with the two most extreme human emotions (hap-
piness and anger) presented through facial, postural, or
vocal cues. For example, cats did not alter their approach
based on human emotion expressions, but they did adjust
their duration of contact and expression of positive
behaviors in Experiment 1.
Behaviorally, the cats showed significantly more posi-
tive behaviors toward their familiar owner in the happy
emotion condition versus the angry emotion condition.
This could suggest that the cats’ positive behavior s were
somewhat influenced by the emotion of their owner, and
that, perhaps, they may have equated their owner’s positive
disposition in the happy condition with a prior history of
reinforcement (as happiness from the owne r may have
signaled affectionate or rewarding behavior toward her
cats). This could be further substantiated by the fact that
the cats perform ed significantly less positive behaviors in
the angry trials and did not react to the emotions of the
unfamiliar experimenter in any particular way. Although
this result would need to be replicated, it fits well with the
two-stage hypothesis, advanced by Udell et al. (2010) and
with the current companion animal literature. Custance and
Mayer (2012 ) found a similar effect in dogs, whereby dogs
consistently approached and attempt ed to ‘comfort’ their
distressed owners as well as strangers. Custance and Mayer
summarized the dogs’ results less as true ‘empathy’ and
more as operant conditioning simply stating that the dogs
were more than likely reinforced for approaching their
distressed owners in the past such that they have learned to
generalize the production of ‘comforting’ behavior to any
human (including strangers) in anticipation of reinforce-
ment. Although the cats in Experiment 1 did not extend
their positive behavior to the unfamiliar experimenter, this
could be a by-product of domestication in that humans
generally do not socialize their cats to the same extent they
do their dogs, thus making the average cat more phobic of
novel humans than the average dog (Bernstein 2007).
Finally, Experiment 2 increased the sample and used
vocal cues to determine whether cats would respond to
emotionally charged conversations (positive or negative) in
an uncertain situation (i.e., novel environm ent and
humans). Overall, the cats were unaffected by the con-
versations in terms of their latency to exit their carrier, their
spatial choices (proximity to owner or experimenter), and
Anim Cogn
123
their overall behavior. Howeve r, based on gaze direction,
the cats looked significantly more at their owner across
conditions than at the experimenter, consistent with other
recent research (Merola et al. 2015). These results could
suggest rudimentary social referencin g, whereby the cats
looked at their owner for situational understanding,
regardless of emotional context. Similar to Merola et al.
(2015), the cats in this experiment were in a novel envi-
ronment (compared to the familiar home setting used in
Experiment 1), and only their owner was familiar. Whereas
Merola et al.’s experiment included an ambiguous object
which the pet and owner were orienting toward, in the
current experiment, the unfamiliar experimenter could be
viewed as an ambiguous element that might inspire refer-
encing from the owner. Although we had expected the cats
to reference the owner more in the negative context, if the
emotion cues disambiguated the intentions or character of
the experimenter equally in both conditions, similar pat-
terns of gaze across conditions might be expected. Alter-
natively, the emotion cues may not have disambiguated the
experimenter at all, also leading to equivalent patterns of
looking, an interpretation that may be more consistent with
the lack of differentiation of cats’ behavior across condi-
tions. Ideally, future studies would include a neutral con-
dition in which no emotion information or context is
provided.
Although the cats’ behaviors in Experiment 2 did not
provide clear evidence of discriminating between emo-
tional valences in novel situations, it is possible that the
subjects were assessing the situation based on different
cues than those that were explicitly manipulated in this
experiment, or expressed their understanding in more
subtle behaviors such as ear orientation (as demonstrated
by Saito and Shinozuka 2013), vocalizations, and other
small body movements. We did not examine these subtle
behaviors because we wished to test whether cats showed
adaptive responses (movement toward or away) in response
to cues that might predict a human’s actions.
One possibility is that domestic cats may not have the
ability to understand huma n emotion as a communicative
cue given their relatively short period of domestication
with humans. This conclusion would be in line with the
Domestication Theory (communicative cue understanding
as an evolved trait; Hare et al. 2002, 2010) but not the two-
stage hypothesis (communicative cue understanding as the
product of experience and reinforcement). It may be the
case that cats need the interdependency of relationship that
dogs and humans share, whereby dogs work for, obey, and
look to humans for guidance in the vast majority of situ-
ations (Berns et al. 2012; Buttelmann and Tomasello 2013;
Custance and Mayer 2012; Kaminski et al. 2013). Dogs
have been selected and bred for their ability to quickly
respond to humans in a highly visible and consistent way,
whereas cats have never faced the same pressures.
Although there is research consistent with the two-stage
hypothesis (Casey and Bradshaw 2008; Karsh 1983; Karsh
and Turner 1988; Miklo
´
si et al. 2005; Turner 1991), the
emphasis on coevolution of understanding between humans
and domestic pets as part of the domestication process may
be a critical component of cognitive capacities such as
emotion cue understanding, and cats may not yet have
coevolved with humans to this extent. An alternative
explanation is that the pre-domestication evolutionary
history of cats as solitary animals, in contrast to the rich
social lives of wild dogs, has not prepared cats with the
cognitive capacity to discriminate emotion cues to the same
degree.
Future directions
Future work in this area should include investigation into
what cues, if any, domestic cats use to predict differences
in human behavior, and how these cues affect the cat–
human relationship and attachment. Future studies shoul d
also compare the behavior of cats with different rearing
histories. It is possible that cats reared by humans since
birth (as opposed to the rescue cats that participated here)
might respond differently in the same tests. A larger
sample of cat–owner dyads would be ideal, as particular
cat–human relationships may influence the results.
Answering specific questions about the ways in which the
cat–human relationship compares to and differs from that
of the dog–human relationship could facilitate new training
methods, more public understanding of cats, and better
welfare practices. In the same way, the research into the
dog–human relationship (Hare and Tomasello 2005; Joly-
Mascheroni et al. 2008; Kaminski et al. 2013) has
improved the way we view our dogs, and this small set of
studies, along with the recent work of other researchers,
has taken steps to further our understanding of the cat–
human interaction.
Acknowledgments The authors declare no competing interests. The
studies comply with the ethical standards of the IACUC of Oakland
University. We would like to thank all of the humans and felines who
have contributed in various ways to this set of experiments. Special
thanks go to Zoe Johnson-Ulrich, Jennifer Hamilton, and Molly
McGuire for their assistance with data collection, and Jonathan
Saulter, Audrey Robeson, Laina Townsend, and Ellen Searle for their
assistance with coding. Thanks to Lisa Welling for helpful comments
on the MS thesis on which this publication is based.
Appendix
See Table 1.
Anim Cogn
123
Table 1 Behavioral ethogram (modified from Leyhausen 1979)
Ears forward
Ears out
Ears back
Body normal
Body low
Body arched
Tail midline or up
Tail tucked (around body,
between legs)
Tail below midline
Sit Cat’s rear end is on the ground
Lay Cat is not standing, or locomoting: may be resting on abdomen, side, or back, with legs extended or tucked
under
Stand still The cat is not in locomotion, but holds an upright posture
Walk-slink Cat is locomoting with chest and abdomen close to the ground, legs not fully extended, may be pressed against
walls or objects
Walk-normal Cat is locomoting with legs extended and relaxed body posture
Rub Cat presses its body, or head, against object or surface
Jump The cat uses its legs and feet to vertically lift off of the ground
Purr A ‘rumbling’ sound which does not require the cat to open its mouth, often accompanied by other relaxed-
type behaviors
Growl A deep ‘groaning’ sound often accompanied by stress-type behaviors
Hiss A sharp exhale of air
Meow A stacatto annunciated vocalization, onomatopeoic in sound ‘merrr-oww’ or ‘rah-ooww’
Yowl/whine A greater intensity meow often with the last vowel sound extended
Paw at door The cat uses one or both front feet to manipulate the door
Eat treats Cat ingests food
Behind E The cat is behind the experimenter’s body
Rub on E Cat presses its body, or head, against the experimenter
Lick E Cat uses tongue in repetition on the experimenter
Climb on E’s lap Cat locomotes onto the experimenter’s crossed legs
Bite E Cat closes its mouth and teeth around experimenter, may be seen when cat is behaving negatively (as in attack)
or positively (as in ‘love bites’’)
Scratch E Cat uses paw and claws in a swiping motion
Paw E Cat uses paw(s) to manipulate an object or touch an object, without the use of claws
Anim Cogn
123
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... Perhaps cats will generally show clearer expectancy violation effects when names are called by familiar voices. Some previous studies have shown cat-human communication effects specific to the owner, with little generalization of social cognitive abilities to a stranger 18,38 . Galvan and Vonk reported that cats differentiate between happy and aggressive expressions of their owner but not a stranger 18 . ...
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Sociality can be broadly defined as the ability and tendency of individuals to reside in social groups with either conspecifics and/or other species. More specifically, sociability relates to the ability and tendency of individuals to display affiliative behaviours in such contexts. The domestic cat is one of the most globally popular companion animals and occupies a diverse range of lifestyles. Despite an arguably short period of domestication from an asocial progenitor, the domestic cat demonstrates an impressive capacity for both intra- and interspecific sociality and sociability. At the same time, however, large populations of domestic cats maintain various degrees of behavioural and reproductive autonomy and are capable of occupying solitary lifestyles away from humans and/or conspecifics. Within social groups, individuals can also vary in their tendency to engage in both affiliative and agonistic interactions, and this interindividual variation is present within free-living populations as well as those managed in confined environments by humans. Considerable scientific enquiry has focused on cats’ social behaviour towards humans (and conspecifics to a much lesser extent) in this latter context. Ontogeny and human selection, in addition to a range of proximate factors including social and environmental parameters and individual cat and human characteristics, have been highlighted as important moderators of cats’ sociability. Such factors may have important consequences regarding individuals’ adaptability to the diverse range of lifestyles that they may occupy. Where limitations to individuals’ social capacities do not enable sufficient e.g. adaption, compromises to their wellbeing may occur. This is most pertinent for cats managed by humans, given that the physical and social parameters of the cats’ environment are primarily dictated by people, but that positive human-selection for traits that enhance cats’ adaptability to such lifestyles appears to be limited. However, limitations in the availability and quality of evidence and equivocal findings may impede the current understanding of the role of certain factors in relation to cat sociability and associations with cat wellbeing, although such literature gaps also present important opportunities for further study. This review aims to summarise what is currently known about the various factors that may influence domestic cats’ sociality and sociability towards both humans and conspecifics, with a predominant focus on cats managed by humans in confined environments. Current limitations, knowledge gaps, and implications for cat wellbeing are also discussed.
... Studies on the social skills of cats are scarce (partly due to the methodological difficulties of testing cats in unfamiliar environments). Cats do seem to recognize emotions such as anger and happiness in people [98,99] and understand human intentions-as they follow pointing gestures [82,100] and can reproduce simple human movements [101]. However, cats are not able to interpret third party interactions [102], an ability present in social species. ...
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Describing the relationship with one’s cat in human terms might reflect an underlying anthropomorphic view of the relationship which might be associated with an owner’s behavior towards their cat and the cat’s living environment. Owners self-categorized the relationship with their cat as either a ‘member of the family’, ‘as a child’, ‘best friend’, or ‘a pet animal’. The extent to which owner- and cat-related factors influence these four relationship descriptions are examined in survey data of approximately 1800 cat owners. Differences in outdoor access, care during absence of the owner, and access to the bedroom are examined between the four relationship perceptions. The owner’s age and household composition, ideas about their cat’s equality, support, and dependency, and whether their cat is a pedigree were significantly associated with relationship description and explained 46% of the variance. Owners who perceive their cat as a child or best friend see their cat as loyal, empathetic, equal to family, and dependent on them for love and care. Their cats are less often left in the care of others, are allowed more often in the bedroom and have less often (unrestricted) outdoor access. Moreover, cats perceived as children are more likely to live in a multi-cat household. Our results provide insight in the factors that are related to different (anthropomorphic) perceptions of the human–cat relationship and how perceptions relate to the living environment of cats.
... It is also questionable to what extent the results of this study can be interpreted in relation to the level of sociability of cats against strangers. Cats are able to distinguish between known and unknown persons and often show preferences for the familiar person ( Galvan and Vonk, 2016 ). However, Vitale and Udell (2019) documented that whether a person was known or unknown to a cat it did not affect their sociabilityrelated behavior. ...
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This study was conducted for the purpose of long-term monitoring of changes in the sociability of group-housed cats towards a familiar caregiver in a private no-kill shelter. The sociability of the monitored cat population was assessed at two-week intervals during one calendar year. A total of 158 animals were rated on a 5-point scale, the individual levels of which represented the level of sociability (1-very friendly cat to 5-very unfriendly cat). The evaluation was performed by visual observation of the cats' response to human approach and contact by one observer. At the first assessment, more than three quarters of the cats (81%) showed very friendly (score of 1) or friendly behavior (score of 2). Of the 88 cats that were evaluated at least twice and at the same time their stay in the shelter terminated during the monitoring period, 56 cats (63.6%) did not change their score (worsen or improve) during their stay in the shelter. Among the cats with an observed change, there was a permanently improved score in a significantly higher number of cats (P < 0.001) during the stay in the shelter than a permanent deterioration (26; 29.5% and 3; 3.4%, respectively). There was a temporary improvement or worsening of the score in 3 cats (3.4%). The improvement in the sociability score during the stay in the shelter mainly concerned cats whose behavior was rated as neutral (score of 3), unfriendly (score of 4) or very unfriendly (score of 5) at the first evaluation. The length of stay of cats in the shelter (LOS) correlated with the level of sociability of the cats during the first (rtau = 0.72, P < 0.001) and the last evaluation (rtau = 0.23, P = 0.007); however, the LOS itself did not predict the level of sociability (P > 0.05). The sociability level at the first assessment was found to be a predictor of the sociability level at the last assessment (P < 0.001). The results of our study suggest that during the stay in the shelter, the cats generally improve their sociability towards a familiar person. Although it appears that cats with lower levels of sociability remain in the shelter for a longer period of time, improvements may increase their adoption potential. Support for programs to increase the cat sociability is needed and should be addressed in further research.
... A study showed that a cat's behavior toward its owner during interactions was affected by their owner's emotional state (Turner and Rieger, 2001). As with dogs, they distinguished between humans' facial expressions and associated postures (Merola et al., 2015;Galvan and Vonk, 2016) and strangers' voices (Quaranta et al., 2020). Dogs/cats can distinguish between signals Call, J., Bräuer, J., Kaminski, J., and Tomasello, M. (2003). ...
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Whilst humans undisputedly shape and transform most of earth's habitats, the number of animals (domestic and wild) living on this planet far outnumbers that of humans. Inevitably, humans have to interact with animals under a variety of circumstances, such as during conservation efforts, wildlife and zoo management, livestock husbandry, and pet keeping. Next to the question of how humans deal with these interactions and conflicts, it is crucial to understand the animal's point of view: How do animals perceive and differentiate between humans? How do they generalize their behavior towards humans? And how does knowledge about humans spread socially? In this Research Topic, we aim to collect original empirical work and review articles to get a more comprehensive and diverse picture on how humans are part of the sensory and cognitive world of non-human animals. We strongly invite contributions that pinpoint shortcomings and limitations in interpreting the available research findings, that provide new cross-disciplinary frameworks (e.g. links between conservation biology and comparative psychology, or human-animal interactions at zoos and animal welfare) and that discuss the applied implementation of these findings (e.g. for conservation attempts or livestock husbandry management).
... Even though Miklosi et al. [39] had already shown differences between dogs and cats in their ability to use human pointing gestures, especially that cats lacked some components of attention-seeking behavior compared with dogs, Pongracz et al. [40] in Hungary demonstrated that cats were indeed able to read and follow human gaze for referential information. Galvan and Vonk [41] determined that cats were only moderately sensitive to human emotions indicated by postural and vocal cues, but particularly so when displayed by their owners as opposed to strangers. The latter implies that learning is probably involved. ...
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After recent publication of several reviews covering research results from the last 35 years of domestic cat studies, a number of important unanswered questions and hypotheses have arisen that could interest active researchers, especially those beginning their academic careers. Some sections of this paper concern methodologies that have yielded new insights and could provide more in the future; other sections concern findings and interpretations of those that need further testing. First, hypotheses arise from combining subjective (or psychological) assessments of cat and human personality traits and observational (ethological) studies of cat–human interactions: e.g., do owners with high attachment to their cats interact differently with them than owners with low attachment levels? New analytical methods of dyadic interaction observations open the door for testing further hypotheses. In particular, the Theme® (Noldus bv, NL) program could be used to determine if there are differences between cat breeds in interaction patterns with people, which is not only of interest to owners but also therapists employing cats in their practices. Cat breed differences have been found using subjective ratings, but these need to be corroborated by direct observational data from the home setting and/or non-invasive colony observations, since ratings based on anthropomorphic projections might not be reliable. This should be done before searching for the genetic basis of such differences. Reliable information on breed differences is also needed before prescribing certain breeds for animal-assisted interventions. A model has predicted that the degree of socialization as a kitten affects cats’ responses to positive and negative experiences with unfamiliar humans and their formation of feline–human relationships later on. This needs to be tested in an ethically approved manner on cats of known socialization status and has enormous consequences for cat adoptions from animal shelters. Observations of human–cat interactions have yielded many correlations, which can be tested by non-invasive manipulations of human behavior in the home setting. Examples of these will be given and are of general interest to the cat-owning public. A review of first findings on social cognition in cats has resulted in further unanswered questions and hypotheses. Finally, two aspects of domestic cat ecology will be considered (effects on wildlife and space utilization), which are of great interest to the public and conservationists alike.
... Other studies have explored the preference that domestic mammals can have for one human emotion over another. In cats, the subjects spent more time in contact with their owner expressing happiness than anger and more positive behaviors were observed (Galvan and Vonk 2016). Goats preferred to initially interact with happy faces when left to move freely in an arena around which were hung pictures of an unfamiliar human expressing happiness or anger . ...
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In the past 20 years, research focusing on interspecific sociocognitive abilities of animals toward humans has been growing, allowing a better understanding of the interactions between humans and animals. This review focuses on five sociocognitive abilities of domestic mammals in relation to humans as follows: discriminating and recognizing individual humans; perceiving human emotions; interpreting our attentional states and goals; using referential communication (perceiving human signals or sending signals to humans); and engaging in social learning with humans (e.g., local enhancement, demonstration and social referencing). We focused on different species of domestic mammals for which literature on the subject is available, namely, cats, cattle, dogs, ferrets, goats, horses, pigs, and sheep. The results show that some species have remarkable abilities to recognize us or to detect and interpret the emotions or signals sent by humans. For example, sheep and horses can recognize the face of their keeper in photographs, dogs can react to our smells of fear, and pigs can follow our pointing gestures. Nevertheless, the studies are unequally distributed across species: there are many studies in animals that live closely with humans, such as dogs, but little is known about livestock animals, such as cattle and pigs. However, on the basis of existing data, no obvious links have emerged between the cognitive abilities of animals toward humans and their ecological characteristics or the history and reasons for their domestication. This review encourages continuing and expanding this type of research to more abilities and species.
... Crossspecies discrimination of the emotional expression of other species also has informative value, particularly in the case of prey-predator relations. There have been reports on the discrimination of human facial expression by animals (cats: Galvan and Vonk 2016;horses: Smith et al. 2016;dogs: Barber et al. 2016, Huber et al. 2013sheep: Davis et al. 1998;monkeys: Guo et al. 2019;pigeons: Stephan et al. 2012;magpies: Lee et al. 2011;archery fish: Newport et al. 2016;wasps: Dyer et al. 2005). However, there have been no studies on the discrimination of human facial expressions in rodents. ...
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Social animals likely recognize emotional expressions in other animals. Recent studies suggest that mice can visually perceive emotional expressions of other mice. In the first experiment, we measured the preference of mice for two different facial expressions (a normal facial expression and an expression of negative emotion such as pain) of rats, mice, and humans. Results revealed that mice showed a slight preference for the normal expression over the face expressing pain in the case of rats, but no preference in the case of others. In the second experiment, we trained mice to discriminate between the two facial expressions in an operant chamber with a touch screen. They could discriminate facial expressions of mice and rats, but they did not show discrimination of human facial expressions. Principal component analysis of the images of stimuli reveals negative correlation between pixel-based dissimilarity of training stimuli and the number of sessions to criterion. The mice showed generalization to novel images of the mouse faces with and without pain but did not maintain their discriminative behavior when new rat faces were shown. These results suggest that mice display category discrimination of conspecific facial expressions but not of other species.
... A succession of half-blinks followed by a prolonged eye narrowing or closure, also known as slow blink sequence, has been suggested to facilitate positive emotional communication between cats and humans (Humphrey et al. 2020). Pet cats are also able to recognize human attentional state (Mertens and Turner 1988;Ito et al. 2016;, read human emotional expression (Merola et al. 2015;Galvan and Vonk 2016;Quaranta et al. 2020), and use human-directed cues, such as pointing (Miklósi et al. 2005;Kraus et al. 2014) and gazing (Pongrácz et al. 2019), to locate hidden food, Cats can also use social referencing when confronted with an ambiguous item (e.g., running fan with plastic ribbons). As defined by Merola et al. (2015), social referencing is a process where "animals look at humans (informer) when facing unfamiliar situations that are difficult to interpret, and act in accordance with the informer's positive or negative emotional reactions". ...
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Research on social cognitive ability in domestic cats is limited. The current study investigated social referencing in cats when exposed to first, a solvable, and then, an unsolvable scenario (i.e., reachable and unreachable treats) in the presence of either an attentive or an inattentive caregiver. Cats expressed more gaze alternation ( P = 0.013), but less interaction with the caregiver ( P = 0.048) and approached the treat container less frequently ( P = 0.017) during the unsolvable test, compared to the solvable test. When in the presence of an attentive caregiver, cats initiated first gaze at the caregiver faster ( P = 0.001); gazed at the caregiver for longer ( P = 0.034); and approached the treat more frequently ( P = 0.040), compared to when the caregiver was inattentive. Significant interaction was observed between test and caregiver’s attentional state on the expression of sequential behavior, a type of showing behavior. Cats exhibited this behavior marginally more with attentive caregivers, compared to inattentive caregivers, but only during the unsolvable test. There was a decrease in sequential behavior during the unsolvable test, compared to solvable test, but this was only seen with inattentive caregivers ( P = 0.018). Our results suggest that gaze alternation is a behavior reliably indicating social referencing in cats and that cats’ social communication with humans is affected by the person’s availability for visual interaction.
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This is a mini review that summarizes what is known from quantitative observational studies of social interactions between domestic cats and humans in both laboratory colonies and the home setting. Only results from data that have been statistically analyzed are included; hypotheses still to be tested will be declared as such. In some cases, the observational data have been combined with independently collected subjective assessments by the owners of the animals' character and owner personality traits to help interpret the data. Further some relevant experimental studies are also included. All social interactions between cats and humans that are discussed below assume that the animals were socialized to people as kittens, the first topic of this review. Such socialized cats show what might be called “friendliness to humans,” which in turn affects human attachment to the cat. The visual and acoustic behavioral elements used to communicate and interact with other cats can be perceived by people and are also employed by the cats when interacting with them. The initiation, and the initiator of social interactions between cats and humans have been shown to influence both the duration of the interaction bout and total interaction time in the relationship. Compliance with the interactional “wishes” of the partner is positively correlated between the cats and the humans over all human-cat dyads examined. Cats do not spontaneously prefer one gender or age cohort of people, but the humans in those cohorts behave differently to the cats causing the latter to react differentially. The dyadic interaction structure has also been shown to differ between women and men and between older and younger adults. Nevertheless, cats—merely their presence but of course their behavior—can affect human moods and human mood differences have been shown to affect the behavior of the cats. Finally, differences have been found between interactions with purebred and non-purebred cats and between younger and older cats.
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Cats’ (Felis catus) communicative behaviour towards humans was explored using a social referencing paradigm in the presence of a potentially frightening object. One group of cats observed their owner delivering a positive emotional message, whereas another group received a negative emotional message. The aim was to evaluate whether cats use the emotional information provided by their owners about a novel/unfamiliar object to guide their own behaviour towards it. We assessed the presence of social referencing, in terms of referential looking towards the owner (defined as looking to the owner immediately before or after looking at the object), the behavioural regulation based on the owner’s emotional (positive vs negative) message (vocal and facial), and the observational conditioning following the owner’s actions towards the object. Most cats (79 %) exhibited referential looking between the owner and the object, and also to some extent changed their behaviour in line with the emotional message given by the owner. Results are discussed in relation to social referencing in other species (dogs in particular) and cats’ social organization and domestication history.
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There has been a marked interest in the socio-cognitive abilities of dogs and their wild relatives. This change after basically total neglect of more than 50 years took place after researchers have recognized that evolution has acted to alter the social behavior set of the dogs in such a way to increase their chances of survival in the anthropogenic environment. Evidently, dogs evolved a social behavior set, which in some respects is functionally equivalent to respective human traits. In this review, we provide an evolutionary description of this process and also contrast different approaches that aim to grasp the key aspects of this change. Contrasting models invoke increased ability for cooperating, utilizing social cues, or modifications in specific social traits (e.g., fear). One key factor seems to be the increased sensitivity of dogs to react to the human social environment in general. They need much less social experience for achieving high levels of social skills in anthropogenic environments in comparison to wolves. We propose a model of social competence that facilitates the comparison of dogs and wolves, but, in addition, it could be utilized for dog-human (infant) and dog-chimpanzee comparisons.
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The domestic cat (Felis silvestris catus) has shared an intertwined existence with humans for thousands of years, living on our city streets and in our homes. Yet, little scientific research has focused on the cognition of the domestic cat, especially in comparison with human's other companion, the domestic dog (Canis lupus familiaris). This review surveys the current status of several areas of cat cognition research including perception, object permanence, memory, physical causality, quantity and time discrimination, cats' sensitivity to human cues, vocal recognition and communication, attachment bonds, personality, and cognitive health. Although interest in cat cognition is growing, we still have a long way to go until we have an inclusive body of research on the subject. Therefore, this review also identifies areas where future research must be conducted. In addition to the scientific value of future work in this area, future research on cat cognition could have an important influence on the management and welfare of pet and free-roaming cats, leading to improved human-cat interactions.
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A sample of 100 adult cat owners participated in a mail survey designed to investigate various aspects of attachment to feline companions. 54 respondents were members of a nationwide computer cat club and 46 were attenders at a cat show in Anaheim, California. 92% of respondents reported preferring cats to all other pets citing ease of care, affection and companionship, and personality as the main reasons. A mean self-rated attachment score of 9.3 on a 10-point scale was obtained. Positive characteristics of the cat were associated with attachment, and the presence of certain problem behaviors did not affect that attachment. Comparisons of the benefits of feline and human companionship showed that affection and unconditional love were the primary benefits of the human-cat relationship, and verbal communication was the primary benefit of the human-human relationship. The findings indicate that, although not a replacement for human contact, feline companions can be a very important source of pleasure and em...
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The question of whether animals have emotions and respond to the emotional expressions of others has become a focus of research in the last decade [1-9]. However, to date, no study has convincingly shown that animals discriminate between emotional expressions of heterospecifics, excluding the possibility that they respond to simple cues. Here, we show that dogs use the emotion of a heterospecific as a discriminative cue. After learning to discriminate between happy and angry human faces in 15 picture pairs, whereby for one group only the upper halves of the faces were shown and for the other group only the lower halves of the faces were shown, dogs were tested with four types of probe trials: (1) the same half of the faces as in the training but of novel faces, (2) the other half of the faces used in training, (3) the other half of novel faces, and (4) the left half of the faces used in training. We found that dogs for which the happy faces were rewarded learned the discrimination more quickly than dogs for which the angry faces were rewarded. This would be predicted if the dogs recognized an angry face as an aversive stimulus. Furthermore, the dogs performed significantly above chance level in all four probe conditions and thus transferred the training contingency to novel stimuli that shared with the training set only the emotional expression as a distinguishing feature. We conclude that the dogs used their memories of real emotional human faces to accomplish the discrimination task. Copyright © 2015 Elsevier Ltd. All rights reserved.