178 research outputs found

    What is it like to be a jealous dog? Commentary on Cook et al. on Dog Jealousy

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    Abstract: Jealousy is a good candidate for comparative studies due to its clear adaptive value in protecting social bonds and affective relationships. Dogs are suitable subjects for investigating the evolution of jealousy, thanks to their rather sophisticated socio-cognitive abilities \u2014 which in some cases parallel those reported for human infants \u2014 and thanks to their long-lasting relationship with humans. The work of Cook and colleagues (2018) addresses the issue of jealousy in dogs through the lens of neuroscience, examining the relationship between the amygdala and jealousy. Their experiment has a number of methodological flaws that prevent distinguishing jealousy from other internal states; it also lacks behavioral indicators that could help in this endeavor. Nevertheless, it is an admirable step towards a multidisciplinary approach to the investigation of non-basic emotions in nonhuman species

    Wolf-like or dog-like? A comparison of gazing behaviour across three dog breeds tested in their familiar environments

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    Human-directed gazing, a keystone in dog\u2013human communication, has been suggested to derive from both domestication and breed selection. The influence of genetic similarity to wolves and selective pressures on human-directed gazing is still under debate. Here, we used the \u2018unsolvable task\u2019 to compare Czechoslovakian Wolfdogs (CWDs, a close-to-wolf breed), German Shepherd Dogs (GSDs) and Labrador Retrievers (LRs). In the \u2018solvable task\u2019, all dogs learned to obtain the reward; however, differently from GSDs and LRs, CWDs rarely gazed at humans. In the \u2018unsolvable task\u2019, CWDs gazed significantly less towards humans compared to LRs but not to GSDs. Although all dogs were similarly motivated to explore the apparatus, CWDs and GSDs spent a larger amount of time in manipulating it compared to LRs. A clear difference emerged in gazing at the experimenter versus owner. CWDs gazed preferentially towards the experimenter (the unfamiliar subject manipulating the food), GSDs towards their owners and LRs gazed at humans independently from their level of familiarity. In conclusion, it emerges that the artificial selection operated on CWDs produced a breed more similar to ancient breeds (more wolf-like due to a less-intense artificial selection) and not very human-oriented. The next step is to clarify GSDs\u2019 behaviour and better understand the genetic role of this breed in shaping CWDs\u2019 heterospecific behaviour

    Red-green color vision in three catarrhine primates

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    The evolution of the red-green visual subsystem in trichromatic primates has been linked to foraging advantages, specifically the detection of either ripe fruits or young leaves amid mature foliage, and to the intraspecific socio-sexual communication, namely the signal of the male rank, the mate choice and the reproductive strategies in females. New data should be added to the debate regarding the evolution of trichromatic color vision. Three catarrhine primates were observed to achieve this goal. The research was performed on captive groups of vervet monkeys (Chlorocebus aethiops), pig-tailed macaques (Macaca nemestrina) and chimpanzees (Pan troglodytes) housed at Parco Natura Viva - Garda Zoological Park (Italy). Using pairs of red-green bags containing the same hidden reward in comparable outdoor enclosures, we recorded the choices by observed individuals (n = 25) to investigate the role of color cues in choosing an object. The results indicate that chimpanzees used red color as cue to choose an object that contains food by showing a preference toward red objects; in contrast, vervet monkeys and pig-tailed macaques do not demonstrate a clear choice based on the color of the object. Our findings highlight the importance of the foraging hypothesis but not rule out the potential role of the intraspecific socio-sexual communication and may serve to add useful information to the debate regarding the adaptive value of the evolution of color vision in order to fill a phylogenetic gap from Old World monkeys to humans. Future studies should address the role of socio-sexual communication, such as the selection of the reproductive partner of both high genetic quality and with compatible genes, to determine how this influenced the evolution of color vision in non-human primates

    Rimozione di sedimenti per fluitazione dal serbatoio di Sernio (SO)

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    Il presente lavoro descrive la rimozione di un ingente quantitativo di sedimenti (circa 100'000 tonnellate) dal serbatoio di Sernio, in provincia di Sondrio, effettuata tra maggio e luglio del 2009. Il sedimento \ue8 stato evacuato per fluitazione (flushing), nel sostanziale rispetto dei vincoli preventivamente stabiliti sulla concentrazione di solidi sospesi (CSS) delle acque scaricate. Tali limitazioni hanno lo scopo di contenere l\u2019impatto delle operazioni sugli ecosistemi acquatici coinvolti. La CSS \ue8 stata controllata regolando il livello nel serbatoio, la portata in uscita e, in un secondo tempo, mediante l\u2019utilizzo di escavatori meccanici. La gestione delle operazioni si \ue8 basata sul costante monitoraggio della CSS poco a valle dell\u2019area di intervento. La campagna di misura \ue8 stata ulteriormente estesa a valle, per un tratto di circa 40 km lungo l\u2019asta dell\u2019Adda, al fine di quantificare la riduzione della CSS per effetto combinato di diluizione e deposizione

    Pet dogs' behavior when the owner and an unfamiliar person attend to a faux rival

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    While dog owners ascribe different emotions to their pets, including jealousy, research on secondary emotions in nonhuman animals is very limited and, so far, only one study has investigated jealousy in dogs (Canis familiaris). This work explores jealousy in dogs one step further. We conducted two studies adapting a procedure devised to assess jealousy in human infants. In each study 36 adult dogs were exposed to a situation in which their owner and a stranger ignored them while directing positive attention towards three different objects: a book, a puppet and a fake dog (Study 1: furry; Study 2: plastic). Overall, the results of both studies do not provide evidence that the behavioral responses of our dogs were triggered by jealousy: we did not find a clear indication that the fake dogs were perceived as real social rivals, neither the furry nor the plastic one. Indeed, dogs exhibited a higher interest (i.e. look at, interact with) towards the fake dogs, but differences in the behavior towards the fake dog and the puppet only emerged in Study 2. In addition, many of the behaviors (protest, stress, attention seeking, aggression) that are considered distinctive features of jealousy were not expressed or were expressed to a limited extent, revealing that dogs did not actively try to regain their owner's attention or interfere with the interaction between the owner and the faux rival. Finally, a differentiated response towards the attachment figure (the owner) and the unfamiliar person (the stranger) did not emerge. Differently from what reported in human infants, dogs' behavior towards the attachment figure and the stranger interacting with the potential competitor (in this case, the fake dog) did not significantly differ: in both studies dogs paid attention to the owner and the stranger manipulating the fake dog to the same extent. In conclusion, we do not exclude that dogs could possess a rudimentary form of jealousy, but we suggest that research on this topic should require the use of a real social interloper (conspecific or human) and more naturalistic procedures

    Automatic Classification of Cat Vocalizations Emitted in Different Contexts

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    Cats employ vocalizations for communicating information, thus their sounds can carry a wide range of meanings. Concerning vocalization, an aspect of increasing relevance directly connected with the welfare of such animals is its emotional interpretation and the recognition of the production context. To this end, this work presents a proof of concept facilitating the automatic analysis of cat vocalizations based on signal processing and pattern recognition techniques, aimed at demonstrating if the emission context can be identified by meowing vocalizations, even if recorded in sub-optimal conditions. We rely on a dataset including vocalizations of Maine Coon and European Shorthair breeds emitted in three different contexts: waiting for food, isolation in unfamiliar environment, and brushing. Towards capturing the emission context, we extract two sets of acoustic parameters, i.e., mel-frequency cepstral coefficients and temporal modulation features. Subsequently, these are modeled using a classification scheme based on a directed acyclic graph dividing the problem space. The experiments we conducted demonstrate the superiority of such a scheme over a series of generative and discriminative classification solutions. These results open up new perspectives for deepening our knowledge of acoustic communication between humans and cats and, in general, between humans and animals

    Do Dogs (Canis lupus familiaris) Make Counterproductive Choices Because They Are Sensitive to Human Ostensive Cues?

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    Dogs appear to be sensitive to human ostensive communicative cues in a variety of situations, however there is still a measure of controversy as to the way in which these cues influence human-dog interactions. There is evidence for instance that dogs can be led into making evaluation errors in a quantity discrimination task, for example losing their preference for a larger food quantity if a human shows a preference for a smaller one, yet there is, so far, no explanation for this phenomenon. Using a modified version of this task, in the current study we investigated whether non-social, social or communicative cues (alone or in combination) cause dogs to go against their preference for the larger food quantity. Results show that dogs' evaluation errors are indeed caused by a social bias, but, somewhat contrary to previous studies, they highlight the potent effect of stimulus enhancement (handling the target) in influencing the dogs' response. A mild influence on the dog's behaviour was found only when different ostensive cues (and no handling of the target) were used in combination, suggesting their cumulative effect. The discussion addresses possible motives for discrepancies with previous studies suggesting that both the intentionality and the directionality of the action may be important in causing dogs' social biases

    Human Analogue Safe Haven Effect of the Owner : Behavioural and Heart Rate Response to Stressful Social Stimuli in Dogs

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    The secure base and safe haven effects of the attachment figure are central features of the human attachment theory. Recently, conclusive evidence for human analogue attachment behaviours in dogs has been provided, however, the owner’s security-providing role in danger has not been directly supported. We investigated the relationship between the behavioural and cardiac response in dogs (N = 30) while being approached by a threatening stranger in separation vs. in the presence of the owner, presented in a balanced order. Non-invasive telemetric measures of heart rate (HR) and heart rate variability (HRV) data during the threatening approaches was compared to periods before and after the encounters. Dogs that showed distress vocalisation during separation (N = 18) and that growled or barked at the stranger during the threatening approach (N = 17) were defined as behaviourally reactive in the given situation. While characteristic stress vocalisations were emitted during separations, the absence of the owner did not have an effect on dogs’ mean HR, but significantly increased the HRV. The threatening approach increased dogs’ mean HR, with a parallel decrease in the HRV, particularly in dogs that were behaviourally reactive to the encounter. Importantly, the HR increase was significantly less pronounced when dogs faced the stranger in the presence of the owner. Moreover, the test order, whether the dog encountered the stranger first with or without its owner, also proved important: HR increase associated with the encounter in separation seemed to be attenuated in dogs that faced the stranger first in the presence of their owner. We provided evidence for human analogue safe haven effect of the owner in a potentially dangerous situation. Similarly to parents of infants, owners can provide a buffer against stress in dogs, which can even reduce the effect of a subsequent encounter with the same threatening stimuli later when the owner is not present

    Domestic cats (Felis silvestris catus) do not show signs of secure attachment to their owners

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    The Ainsworth Strange Situation Test (SST) has been widely used to demonstrate that the bond between both children and dogs to their primary carer typically meets the requirements of a secure attachment (i.e. the carer being perceived as a focus of safety and security in otherwise threatening environments), and has been adapted for cats with a similar claim made. However methodological problems in this latter research make the claim that the cat-owner bond is typically a secure attachment, operationally definable by its behaviour in the SST, questionable. We therefore developed an adapted version of the SST with the necessary methodological controls which include a full counterbalance of the procedure. A cross-over design experiment with 20 cat-owner pairs (10 each undertaking one of the two versions of the SST first) and continuous focal sampling was used to record the duration of a range of behavioural states expressed by the cats that might be useful for assessing secure attachment. Since data were not normally distributed, non-parametric analyses were used on those behaviours shown to be reliable across the two versions of the test (which excluded much cat behaviour). Although cats vocalised more when the owner rather the stranger left the cat with the other individual, there was no other evidence consistent with the interpretation of the bond between a cat and its owner meeting the requirements of a secure attachment. These results are consistent with the view that adult cats are typically quite autonomous, even in their social relationships, and not necessarily dependent on others to provide a sense of security and safety. It is concluded that alternative methods need to be developed to characterise the normal psychological features of the cat-owner bond

    Handler beliefs affect scent detection dog outcomes

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    Our aim was to evaluate how human beliefs affect working dog outcomes in an applied environment. We asked whether beliefs of scent detection dog handlers affect team performance and evaluated relative importance of human versus dog influences on handlers’ beliefs. Eighteen drug and/or explosive detection dog/handler teams each completed two sets of four brief search scenarios (conditions). Handlers were falsely told that two conditions contained a paper marking scent location (human influence). Two conditions contained decoy scents (food/toy) to encourage dog interest in a false location (dog influence). Conditions were (1) control; (2) paper marker; (3) decoy scent; and (4) paper marker at decoy scent. No conditions contained drug or explosive scent; any alerting response was incorrect. A repeated measures analysis of variance was used with search condition as the independent variable and number of alerts as the dependent variable. Additional nonparametric tests compared human and dog influence. There were 225 incorrect responses, with no differences in mean responses across conditions. Response patterns differed by condition. There were more correct (no alert responses) searches in conditions without markers. Within marked conditions, handlers reported that dogs alerted more at marked locations than other locations. Handlers’ beliefs that scent was present potentiated handler identification of detection dog alerts. Human more than dog influences affected alert locations. This confirms that handler beliefs affect outcomes of scent detection dog deployments
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