Juliane Kaminski

Body orientation and face orientation: two factors controlling apes' begging behavior from humans

A number of animal species have evolved the cognitive ability to detect when they are being watched by other individuals. Precisely what kind of information they use to make this determination is unknown. There is particular controversy in the case of the great apes because different studies report conflicting results. In experiment 1, we presented chimpanzees, orangutans, and bonobos with a situation in which they had to request food from a human observer who was in one of various attentional states. She either stared at the ape, faced the ape with her eyes closed, sat with her back towards the ape, or left the room. In experiment 2, we systematically crossed the observer’s body and face orientation so that the observer could have her body and/or face oriented either towards or away from the subject. Results indicated that apes produced more behaviors when they were being watched. They did this not only on the basis of whether they could see the experimenter as a whole, but they were sensitive to her body and face orientation separately. These results suggest that body and face orientation encode two different types of information. Whereas face orientation encodes the observer’s perceptual access, body orientation encodes the observer’s disposition to transfer food. In contrast to the results on body and face orientation, only two of the tested subjects responded to the state of the observer’s eyes.

The domestication hypothesis for dogs' skills with human communication: a response to Udell et al. (2008) and Wynne et al. (2008)

Domestic dogs have special skills in comprehending human communicative behaviours (Hare & Tomasello 2005; Miklosi 2008). Dogs across a range of breeds use human communicative cues such as pointing or physical markers to find food that is hidden in one of two hiding places (controls rule out the use of olfactory cues; Cooper et al. 2003; Hare & Tomasello 2005; Miklosi & Soproni 2006). In direct comparisons, dogs are even more skilled than chimpanzees at using human communicative cues when searching for food (Hare et al. 2002; Bra¨uer et al. 2006). Moreover, a number of studies suggest that dogs understand human gestures communicatively, as a number of possible low-level explanations have been ruled out (e.g. only responding to movement; reflexively coorienting; using only familiar cues, etc.; Hare et

How dogs know when communication is intended for them

Domestic dogs comprehend human gestural communication in a way that other animal species do not. But little is known about the specific cues they use to determine when human communication is intended for them. In a series of four studies, we confronted both adult dogs and young dog puppies with object choice tasks in which a human indicated one of two opaque cups by either pointing to it or gazing at it. We varied whether the communicator made eye contact with the dog in association with the gesture (or whether her back was turned or her eyes were directed at another recipient) and whether the communicator called the dogs name (or the name of another recipient). Results demonstrated the importance of eye contact in human-dog communication, and, to a lesser extent, the calling of the dogs name--with no difference between adult dogs and young puppies--which are precisely the communicative cues used by human infants for identifying communicative intent. Unlike human children, however, dogs did not seem to comprehend the humans communicative gesture when it was directed to another human, perhaps because dogs view all human communicative acts as directives for the recipient.

Focus on the essential: all great apes know when others are being attentive

When begging for food, all great ape species are sensitive to a human’s attention. However, studies investigating which cues are relevant for chimpanzees to assess the attentional state of others have produced highly inconsistent results. Some have suggested chimpanzees differentiate attention based on the status of the face or even the eyes, while others have indicated that body posture alone is the relevant cue. Kaminski et al. (Anim Cogn 7:216–223, 2004) compared the behaviour of chimpanzees, bonobos and orangutans while begging for food from a human experimenter who systematically varied his face and body orientation. Their results indicated that both factors, face and body orientation, affect apes’ begging behaviour. The authors claimed that while body orientation provides information about the experimenter’s general disposition to offer food, the visibility of the face provides information about the human’s attentional state. In the current study, we tested this hypothesis with all four great apes species. However, unlike Kaminski et al. (Anim Cogn 7:216–223, 2004), the experimenter was able to hand over food regardless of body orientation. The results show that as soon as the offering of the food was no longer restricted, the orientation of the face became the key factor. Therefore, we present the first evidence that all great ape species are able to assess the attentional state of a recipient based on the orientation of the face.

Paedomorphic Facial Expressions Give Dogs a Selective Advantage

How wolves were first domesticated is unknown. One hypothesis suggests that wolves underwent a process of self-domestication by tolerating human presence and taking advantage of scavenging possibilities. The puppy-like physical and behavioural traits seen in dogs are thought to have evolved later, as a byproduct of selection against aggression. Using speed of selection from rehoming shelters as a proxy for artificial selection, we tested whether paedomorphic features give dogs a selective advantage in their current environment. Dogs who exhibited facial expressions that enhance their neonatal appearance were preferentially selected by humans. Thus, early domestication of wolves may have occurred not only as wolf populations became tamer, but also as they exploited human preferences for paedomorphic characteristics. These findings, therefore, add to our understanding of early dog domestication as a complex co-evolutionary process.

Comparing dogs and great apes in their ability to visually track object transpositions

Knowing that objects continue to exist after disappearing from sight and tracking invisible object displacements are two basic elements of spatial cognition. The current study compares dogs and apes in an invisible transposition task. Food was hidden under one of two cups in full view of the subject. After that both cups were displaced, systematically varying two main factors, whether cups were crossed during displacement and whether the cups were substituted by the other cup or instead cups were moved to new locations. While the apes were successful in all conditions, the dogs had a strong preference to approach the location where they last saw the reward, especially if this location remained filled. In addition, dogs seem to have especial difficulties to track the reward when both containers crossed their path during displacement. These results confirm the substantial difference that exists between great apes and dogs with regard to mental representation abilities required to track the invisible displacements of objects.

Dogs steal in the dark

All current evidence of visual perspective taking in dogs can possibly be explained by dogs reacting to certain stimuli rather than understanding what others see. In the current study, we set up a situation in which contextual information and social cues are in conflict. A human always forbade the dog from taking a piece of food. The part of the room being illuminated was then varied, for example, either the area where the human was seated or the area where the food was located was lit. Results show that dogs steal significantly more food when it is dark compared to when it is light. While stealing forbidden food the dog’s behaviour also depends on the type of illumination in the room. Illumination around the food, but not the human, affected the dogs’ behaviour. This indicates that dogs do not take the sight of the human as a signal to avoid the food. It also cannot be explained by a low-level associative rule of avoiding illuminated food which dogs actually approach faster when they are in private. The current finding therefore raises the possibility that dogs take into account the human’s visual access to the food while making their decision to steal it.

Citizen Science as a New Tool in Dog Cognition Research

Family dogs and dog owners offer a potentially powerful way to conduct citizen science to answer questions about animal behavior that are difficult to answer with more conventional approaches. Here we evaluate the quality of the first data on dog cognition collected by citizen scientists using the Dognition.com website. We conducted analyses to understand if data generated by over 500 citizen scientists replicates internally and in comparison to previously published findings. Half of participants participated for free while the other half paid for access. The website provided each participant a temperament questionnaire and instructions on how to conduct a series of ten cognitive tests. Participation required internet access, a dog and some common household items. Participants could record their responses on any PC, tablet or smartphone from anywhere in the world and data were retained on servers. Results from citizen scientists and their dogs replicated a number of previously described phenomena from conventional lab-based research. There was little evidence that citizen scientists manipulated their results. To illustrate the potential uses of relatively large samples of citizen science data, we then used factor analysis to examine individual differences across the cognitive tasks. The data were best explained by multiple factors in support of the hypothesis that nonhumans, including dogs, can evolve multiple cognitive domains that vary independently. This analysis suggests that in the future, citizen scientists will generate useful datasets that test hypotheses and answer questions as a complement to conventional laboratory techniques used to study dog psychology.

Dogs (Canis familiaris) are Adapted to Receive Human Communication

In recent years, evidence has been accumulating that domestic dogs (Canis familiaris)havespecializedskills in readinghuman-givencommunicativecues (e.g., pointing gestures). These skills seem to be the result of selection pressures during the process of domestication and therefore an adaptation to the dogs’ environment, namely human societies. Also, current evidence suggests that dogs’ understanding of human gestures is more flexible than was formerly thought. More specifically, dogs distinguish between intended communicative acts and non-intended but targetdirected behaviours, suggesting that dogs’ behaviour in this domain reflects important aspects of the comprehension of human communicative intentions. However, while children also eavesdrop on communicative interactions between third parties, dogs do not. This can be taken as evidence that dogs take human gestures as directives, while children see them as (sometimes) informative. Also dogs’ understanding of gestures seems to be generally more behaviourally based whereas children comprehend gestures in the context of joint attentional interactions. A species’ cognitive adaptations, like its morphological adaptations, reflect the ecological contexts in which it has evolved. Domestic dogs (Canis familiaris) have evolved in a very special ecological context. Approximately fifteen thousand years ago, wolves (Canis lupus) entered human societies and were domesticated to become one of the most successful species on the planet, the domestic dog (Vila et al. 1997). Since then dogs have been part of human societies and interact with humans in many different ways; they help to hunt, to herd, to protect, etc. (Coppinger and Coppinger 2001). For living in the human world, dogs may have evolved specialized cognitive mechanisms which enable them to interact with human beings and which resemble some of humans’ cognitive skills (Hare and Tomasello 2005), making dogs an interesting model for questions regarding the evolution of cognition. J. Kaminski Sub-Department of Animal Behaviour, University of Cambridge, High Street, Madingley, Cambridge CB3 8AA UK e-mail: Kaminski@eva.mpg.de A. Berthoz and Y. Christen (eds.), Neurobiology of “Umwelt”: How Living Beings 103 Perceive the World, Research and Perspectives in Neurosciences, c

Do domestic dogs interpret pointing as a command

Domestic dogs comprehend human gestural communication flexibly, particularly the pointing gesture. Here, we examine whether dogs interpret pointing informatively, that is, as simply providing information, or rather as a command, for example, ordering them to move to a particular location. In the first study a human pointed toward an empty cup. In one manipulation, the dog either knew or did not know that the designated cup was empty (and that the other cup actually contained the food). In another manipulation, the human (as authority) either did or did not remain in the room after pointing. Dogs ignored the human’s gesture if they had better information, irrespective of the authority’s presence. In the second study, we varied the level of authority of the person pointing. Sometimes this person was an adult, and sometimes a young child. Dogs followed children’s pointing just as frequently as they followed adults’ pointing (and ignored the dishonest pointing of both), suggesting that the level of authority did not affect their behavior. Taken together these studies suggest that dogs do not see pointing as an imperative command ordering them to a particular location. It is still not totally clear, however, if they interpret it as informative or in some other way.