Size communication in domestic dog, Canis familiaris, growls

Size Communication in Dogs

A.M. Taylor, D. Reby, K. McComb

Size communication in domestic dog, Canis familiaris, growls

Animal Behaviour, Volume 79, Issue 1, January 2010, Pages 205–210

ABSTRACT

In many species, body size is a key determinant of the outcome of agonistic interactions, and receivers are expected to attend to size cues when assessing competitors' signals. Several mammal vocalizations, including domestic dog growls, encode reliable information about caller body size in the dispersion of formant frequencies. To test whether adult domestic dogs attend to formant dispersion when presented with the growls of their conspecifics, we played recordings of resynthesized growls where the size-related variation in formant frequency spacing was manipulated independently of all other parameters. Subjects from three different size groups (small, medium and large dogs) were presented with playbacks of growls where formant frequencies had been rescaled to correspond to a dog 30% smaller or 30% larger than themselves. While large dogs systematically displayed more motivation to interact when growls simulated a smaller intruder, small dogs did not respond differentially to the playback conditions. However, the small dogs responded significantly less than all other size groups to both playback conditions. Our results suggest that domestic dogs are able to perceive size-related information in growls, and more specifically that they are able to adapt their behavioural response as a function of the perceived intruder's size relative to their own.

A comparison of dog–dog and dog–human play behaviour

Dog-Dog vs Human-Dog Playing

Nicola J Rooney, John W.S Bradshaw, Ian H Robinson

A comparison of dog–dog and dog–human play behaviour

Applied Animal Behaviour Science, Volume 66, Issue 3, 29 February 2000, Pages 235–248

Abstract

In the popular literature, it is often assumed that a single conceptual framework can be applied to both dog–dog and dog–human interactions, including play. We have, through three studies, tested the hypothesis that dog–dog and dog–human play are motivationally distinct. In an observational study of dogs being walked by their owners (N=402), dogs which were walked together, and had opportunities to play with one another, played with their owners with the same frequency as dogs being walked alone. This finding was supported by a questionnaire survey of 2585 dog owners in which dogs in multi-dog households played slightly more often with their owners than dogs in single-dog households. The performance of dog–dog play does not, therefore, seem to suppress the dogs' motivation to play with their owners as would be predicted if they were motivationally interchangeable. In an experimental comparison of dog–dog and dog–human toy-centred play, the dogs were more likely to give up on a competition, to show and present the toy to their play partner, if that partner was human. When two toys were available, dogs playing with other dogs spent less time showing interest in both toys and possessed one of the toys for longer, than dogs playing with people. Overall, the dogs were more interactive and less likely to possess the object when playing with a person. We conclude that dog–dog and dog–human play are structurally different, supporting the idea that they are motivationally distinct. We therefore suggest there is no reason to assume that the consequences of dog–dog play can be extrapolated to play with humans.

The breakfast effect: Dogs (Canis familiaris) search more accurately when they are less hungry

Holly C. Miller, Charlotte Bender

The breakfast effect: Dogs (Canis familiaris) search more accurately when they are less hungry

Behavioural Processes, Available online 29 September 2012

Abstract

We investigated whether the consumption of a morning meal (breakfast) by dogs (Canis familiaris) would affect search accuracy on a working memory task following the exertion of self-control. Dogs were tested either 30 or 90 min after consuming half of their daily resting energy requirements (RER). During testing dogs were initially required to sit still for 10 min before searching for hidden food in a visible displacement task. We found that 30 min following the consumption of breakfast, and 10 min after the behavioral inhibition task, dogs searched more accurately than they did in a fasted state. Similar differences were not observed when dogs were tested 90 min after meal consumption. This pattern of behavior suggests that breakfast enhanced search accuracy following a behavioral inhibition task by providing energy for cognitive processes, and that search accuracy decreased as a function of energy depletion.

Dogs, Canis familiaris, communicate with humans to request but not to inform

Juliane Kaminski, Martina Neumann, Juliane Bräuer, Josep Call, Michael Tomasello

Dogs, Canis familiaris, communicate with humans to request but not to inform

Animal Behaviour, Volume 82, Issue 4, October 2011, Pages 651–658

ABSTRACT

Dogs are especially skilful at comprehending human communicative signals. This raises the question of whether they are also able to produce such signals flexibly, specifically, whether they helpfully produce indicative (‘showing’) behaviours to inform an ignorant human. In experiment 1, dogs indicated the location of an object more frequently when it was something they wanted themselves than when it was something the human wanted. There was some suggestion that this might be different when the human was their owner. So in experiment 2 we investigated whether dogs could understand when the owner needed helpful information to find a particular object (out of two) that they needed. They did not. Our findings, therefore, do not support the hypothesis that dogs communicate with humans to inform them of things they do not know.

Refutation of the stereotype of a “killer dog” in light of the behavioral interpretation of human corpses biting by domestic dogs

Krzysztof Maksymowicz, Krzysztof Marycz, Joanna Czogała, Tomasz Jurek

Refutation of the stereotype of a “killer dog” in light of the behavioral interpretation of human corpses biting by domestic dogs

Journal of Veterinary Behavior: Clinical Applications and Research, Volume 6, Issue 1, January–February 2011, Pages 50–56

Abstract

Postmortem bite injuries caused by domestic dogs are not very common, but because of their special character and concomitant occurrence, explaining them requires extensive forensic expertise and knowledge of the basics of animal behavior. The authors have analyzed reasons for the damage of human body caused by the dogs, with suspicion of fatal biting. Characteristics of the wounds, the description of the crime scene, the available psychophysical data of the animals, and the likely motives for the behavior exhibited by the dogs were examined. In the course of the study, it was concluded that the wounds were postmortem in nature and the crime scene character was atypical for the satisfaction of the scavenging instinct. Moreover, detailed analysis of the cases described in the text later revealed that uncharacteristic anxiety reactions with the sequent satisfaction of the exaggerated form of care-giving and the loyalty to the guardians were the most likely motivations for the actions of the dogs in the face of human death.