Both human and nonhuman primates use imperative pointing to request a desired object from another individual. Gaze alternation often accompanies such pointing gestures, and in species that have no hands this can in itself function as imperative pointing. Dogs have exceptional skills in communicating with humans. The early development of these skills is suggested to have been facilitated by domestication. Adult wolves socialized with humans can use human-provided information to find food in various situations, but it is unclear whether they would use gaze alternation to show their human partner a target location they cannot reach on their own. In our experiment, we tested wolves and dogs in a task where they could indicate an out-of-reach food location to one of two human partners. One partner reacted in a cooperative way and gave the food hidden in the indicated location to the subject whereas the other responded in a competitive way and ate the food herself. Our results suggest that wolves, as well as dogs, use ‘showing’ behaviours to indicate a food location to a human partner, and that both can adjust their communication to the cooperativeness of their human partners, showing more indicating signals in the presence of the cooperative partner than in the presence of the competitive one. We conclude that wolves and dogs, both kept in packs under the same conditions, can use humans as cooperative partners, and point imperatively in order to receive a desired out-of-reach object. It seems that intensive socialization with humans enables both wolves and dogs to communicate cooperatively about a food location with humans, most probably relying on skills that evolved to promote social coordination within their packs.

Deception, the use of false signals to modify the behaviour of the receiver, occurs in low frequencies even in stable signalling systems. For example, it can be advantageous for subordinate individuals to deceive in competitive situations. We investigated in a three-way choice task whether dogs are able to mislead a human competitor, i.e. if they are capable of tactical deception. During training, dogs experienced the role of their owner, as always being cooperative, and two unfamiliar humans, one acting 'cooperatively' by giving food and the other being 'competitive' and keeping the food for themselves. During the test, the dog had the options to lead one of these partners to one of the three potential food locations: one contained a favoured food item, the other a non-preferred food item and the third remained empty. After having led one of the partners, the dog always had the possibility of leading its cooperative owner to one of the food locations. Therefore, a dog would have a direct benefit from misleading the competitive partner since it would then get another chance to receive the preferred food from the owner. On the first test day, the dogs led the cooperative partner to the preferred food box more often than expected by chance and more often than the competitive partner. On the second day, they even led the competitive partner less often to the preferred food than expected by chance and more often to the empty box than the cooperative partner. These results show that dogs distinguished between the cooperative and the competitive partner, and indicate the flexibility of dogs to adjust their behaviour and that they are able to use tactical deception.

Attending to the perception of others may help individuals gaining information from conspecifics, or help in competitive situations. Dogs (Canis familiaris) are attentive to humans' signals and their attentional state. We investigated whether dogs of different breed groups differ in their ability to pay attention to human's perception, first according to the genetic relatedness between dog breeds, and second according to working style differences. Once dogs had learned to leave forbidden food on the floor, they were confronted with 2 food items to which only they had unrestricted visual access. The owners saw either none or 1 food item through a transparent barrier. Our results showed that dogs pay attention to the perception of humans, whereby differences between breed groups became obvious. Within different genetic groups, ancient and hunting type dogs performed similarly, they were more attentive to their owners' perception than shepherd and the mastiff type dogs. When comparing dogs classified according to their working style, independent workers and family dogs were attentive to the owner's perception, while cooperative workers seemed not. The dogs' choice could not be explained by a general or training induced preference for eating behind an opaque screen, or by an influence of the owner's possible intention to prevent the dog from taking the food item he could see. Our study confirms that dogs are attentive/sensitive to human's perception, but genetic and working style differences among the breeds, as well as dog sport experiences explain part of the variation seen in their performance. (PsycINFO Database Record