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.

Behaviour of smaller and larger dogs: Effects of training methods, inconsistency of owner behaviour and level of engagement in activities with the dog

Behavior of Smaller and Larger Dogs

Christine Arhant, Hermann Bubna-Littitz, Angela Bartels, Andreas Futschik, Josef Troxler

Behaviour of smaller and larger dogs: Effects of training methods, inconsistency of owner behaviour and level of engagement in activities with the dog

Applied Animal Behaviour Science, Volume 123, Issues 3–4, March 2010, Pages 131–142

Abstract

The owner's behaviour is regarded to be a possible cause of unfavourable behaviour such as poor obedience or excitability in smaller dogs. The aim of this study was to investigate whether owner behaviour such as use of training methods, inconsistency in the owner's behaviour or engagement in shared activities differs between owners of smaller (<20 kg) and larger dogs (≥20 kg) and whether associations between the owner's and the dog's behaviour in smaller dogs differ from those in larger dogs. For this purpose, a questionnaire-based survey via postal mailing was conducted in an urban and suburban population of pet dog owners (response rate: 28%). Statistical analysis of 1276 questionnaires involved descriptive statistics, Chi²-test, t-tests and Spearman correlations. Our results confirm that smaller dogs are seen as less obedient (P < 0.001), more aggressive and excitable (P < 0.001) and more anxious and fearful (P < 0.001). Smaller dog owners reported being more inconsistent in interactions with their dog (P < 0.001) and engaging less in training and play activities (P < 0.001) than larger dog owners. More consistent owner behaviour (r_s = −0.4, P < 0.001) and more frequent engagement in training and play activities (r_s = 0.4, P < 0.001) correlated with better obedience in smaller dogs. No marked differences were found in the types of training methods used with smaller and larger dogs, but owners of smaller dogs reported slightly less use of punishment (P = 0.007). In smaller and larger dogs, a more frequent use of punishment was associated with increased aggression and excitability (smaller: r_s = 0.3, P < 0.001; larger: r_s = 0.2, P < 0.001) as was a more frequent use of reward-based responses to unwanted dog behaviour such as calming or distracting the dog (r_s = 0.2, P < 0.001). The main result of our study was that increased anxiety and fear was related to a more frequent use of punishment in smaller (r_s = 0.2, P < 0.001) but not in larger dogs. We conclude that smaller dog owners could significantly improve obedience in their dogs by being more consistent in interactions and engaging regularly in play and training activities with them. Behavioural problems could be reduced by avoiding habits of punishment that might reinforce fear or fear-related aggression.

Physical size matters in the domestic dog's (Canis lupus familiaris) ability to use human pointing cues

William S. Helton, Nicole D. Helton

Physical size matters in the domestic dog's (Canis lupus familiaris) ability to use human pointing cues

Behavioural Processes, Volume 85, Issue 1, September 2010, Pages 77–79

Abstract

Researchers have reported differences between breeds of dogs in their ability to utilize human gestures (Wobber et al., 2009). These reports could either be the result of underlying differences in inherent communication abilities or differences in physical capacities amongst breeds. One physical difference between breeds which may make a difference in using visual cues is relative size. Larger dogs should, all other things being equal, have greater inter-ocular distances and this may improve their visual abilities for some tasks. This hypothesis was tested in the present study by comparing the performance of larger (>22.7 kg) and smaller (<22.7 kg) dogs on a pointing choice task. Larger dogs did perform better on this task than smaller dogs (P = .03). Researchers need to be careful when making comparisons between breeds to first consider physical differences before assuming any inherent cognitive differences.