Introduction
Since domestication began more than 10 000 years ago (Pang et al., 2009; see also Clutton-Brock, Chapter 2; vonHoldt & Driscoll, Chapter 3), dogs have been living in a human-dominated niche in which they are likely to enjoy advantages if they are able to communicate and cooperate successfully with people (Miklósi et al., 2004; Bradshaw & Rooney, Chapter 8). As such, dogs are thought to have evolved cognitive-emotional traits analogous to the social skills that differentiate humans from other primates (Hare et al., 2005; Topál et al., 2009a). Accordingly, investigating the cognition of domestic dogs provides a potentially exciting opportunity to reveal which cognitive traits have functional relevance in the present social life of humans (Virányi et al., 2008a).
Recent intensive research focusing on dogs’ social interactions and communication with humans has revealed that dogs perform more like humans in some communicative and cooperative tasks than any other animal species (Lakatos et al., 2009; Soproni et al., 2001). In some of these tasks, dogs outperform other species that are more closely related to humans, such as chimpanzees (Pan troglodytes) (Brauer et al., 2006; Hare et al., 2002; but see Mulcahy & Hedge, 2012). These intriguing dog–human similarities are often assumed to originate from the dog's adaptation to the human environment, and are partly due to their life-long experiences with humans and the influence that this exerts on their cognitive development (Udell et al., 2010, Miklósi & Tópal, 2011). Dogs typically grow up in human families and develop attachments and dependent relationships analogous to those between children and their parents (Topál et al., 1998). This developmental environment can foster a variety of mechanisms ranging from classical conditioning (Bentosela et al., 2008) to more complex modifications of cognitive and emotional processes, such as the ontogenetic process of “enculturation” that has been proposed to result in enhanced cognitive abilities in non-human primates raised by humans (Hare et al., 2005). Consequently, many argue that dog behavior and cognition have been modified in ways that help dogs to be socially integrated into human groups.
For both theoretical and practical reasons, it is important to ask to what extent aspects of dog behavior and cognition have either been genetically modified during the course of domestication or altered by individual experiences and training.