Based on results of molecular phylogenetic analyses and archaeological evidences, most researchers believe that the dog is descended from the wolf and that east Asia was the central place for the early events of domestication around 15,000-20,000BP. Many different theories of domestication have been proposed in respect of the evolutionary mechanism, and each theory can explain a particular aspect of the process which has different evolutionary backgrounds by its stage and phase. The dog is established in modern society as a companion animal. It has physiological and psychological benefits to human, which include facilitating therapy, reducing stress, and socialization. In addition to that, the dog has positive effects on child development and elderly people.

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Recent researches have shown that dogs (Canis familiaris) possess a number of social cognitive abilities and communicate with humans in unique ways. Several researches suggest that dogs do not only use the overt features of humans (e.g., pointing, gaze) to find a hidden food in an object choice task, but also recognize the covert aspects of humans (e.g., knowledge) to predict the actions of them. This paper reviews evidence showing such excellent social cognition in dogs. Several comparisons between wolves and dogs suggest that human-like social skills by dogs have evolved as a by-product of domestication. Besides, some researchers argue the possibility of acquisition of similar social skills between dogs and humans through convergent cognitive evolution, which enabled them to communicate. The study of social cognitive skills in dogs will broaden our understanding of comparative social cognition.

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A special relationship between human and dog is considered to be established by dog's characteristic social skill and cognitive ability, based on adequate emotional and affiliative behavior. It has been emphasized that puppy's experience in its developing period is prerequisite for dog's socialization to human. On the other hand, it is also indicated that if maternal environment is deprived, it would cause various behavioral problems of impairing dog's sociality in adulthood, such as anxiety, fear-related behavior, or aggression toward human. These suggest that maternal environment in dogs could have a large impact on the human-dog relationship. In various mammalian species including human, the quality of mother-infant relationships has been shown to affect neurobehavioral development related to sociality. However, there are few studies in dogs. This article discusses how dog's sociality can be influenced by maternal environment in each developmental stage of puppy, and underlying predictable mechanisms for it. The developmental approach to dog's sociality will be beneficial for better understanding of a special relationship between human and dog.

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Dogs have shared a common environment and similar selective pressures with humans through the time of domestication. About 60 years ago, Lorenz (1949) proposed that in many ways dogs are possibly more human-like than any other animals, including nonhuman primates. Only recently, however, scientific studies have evinced the specialized social skills of dogs. The relationships between humans and domestic dogs have deepened and changed, which highlighted or rather increased practical and ethical problems on the relationship between these two species. Some dogs are considered as members of the family, while some others are ill-treated and abandoned due to their behavior problems. In an attempt to examine how animal psychology can contribute to the dog-human relationship in modern society, this article reviews the application of behavior technology to behavior problems of dogs, the problems arising from the massive disparities in the treatment of dogs, and the view and traditional attitude towards animals in the theories of animal ethics.

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We observed the behaviors of domestic dogs and their keepers in an off-leash dog park, and elucidated the relationships between them as well as with other humans and dogs who visited the park. The dogs and their keepers spent half of their time in proximity. The keepers employed physically stable behaviors such as talking and touching as tools to interact with their dogs. On the other hand, the dogs employed proximity regulations as tools to interact with their keepers. The keepers and their dogs tended to engage in intra-species more frequently than inter-species interactions. The keepers interacted with their dogs more actively on weekdays than on weekends and holidays. The women interacted with their dogs and other humans more actively than the men did.

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Two lists of human personality-trait descriptors (386 descriptors in List A and 382 descriptors in List B) were judged by university students (n=230 for List A, and n=138 for List B). The data were summarized in terms of the “acceptance score” of each descriptor, which is the percentage of students who agreed that the descriptor was suitable for describing dog personalities. As expected, descriptors for language or complex mental mechanisms had low scores. The characteristics of the judges (e.g., their age and affection for dogs) had no effects on anthropomorphism reflected in the percentage of descriptors admitted for describing dog personalities. Furthermore, we conducted a personality questionnaire consisting of descriptors with an acceptance score of 70% or more. With this questionnaire, another group of university students (n=325) and dog owners (n=217) were requested to assess their friends (a friend per student) and dogs (a dog per owner), respectively. Factor analyses of these two sets of data revealed a similar “Big-Five” personality structures in humans and dogs.

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According to the experimental studies conducted by European and American researchers, domestic dogs are good performers in choosing a container based on gestures provided by humans. Some researchers have argued that this ability is a product of domestication. We investigated whether family dogs in Japan can use social cues to locate food hidden in one of two small containers (pots). The tested cues were (1) pointing to the target pot with the contralateral hand (i.e., cross-body pointing), (2) turning the head to the target pot, and (3) kneeling behind the target pot (i.e., local enhancement). The performance was poor in the present study compared with the previous studies conduced in European/American countries. As family dogs are well controlled in these countries compared to those in Japan, our data seem to challenge the domestication hypothesis and support the claim that social skill learning plays a critical role in this task.

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Animal study in modern psychology has started as animal model study for general theory of human behavior. I examined pigeons and songbirds as models of human visual cognition and human auditory cognition respectively. Due to difference in anatomical structures and evolutionary history between the birds and humans, research to understand human cognition by avian models has limitation. On the other hand, researches with birds, far distant animals from human beings, are crucially important to understand visual and auditory cognitive faculty in general, because these faculties are not human-specific but widely spread in animal kingdom.

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The nature and extent of dolphin intelligence has long intrigued humans. Unequivocal answers to the question “how intelligent are dolphins?” have proven evasive due to both the existing myriad views of intelligence and the ambiguity of much spontaneous dolphin behavior. In this paper, we focus on one aspect of intelligence, namely the ability to plan one's behavior in a meaningful way. The generalized ability to create novel and appropriate behavioral plans when confronted with new problems has obvious evolutionary advantages, but has been found in relatively few species. The studies reported in this paper demonstrate planning behaviors in bottlenose dolphins (Tursiops truncatus) in conditions quite different from those that occur during dolphin foraging and mating (two areas in which wild dolphins may engage in planning). The dolphins' ability to plan their behaviors in these novel contexts provides additional evidence that generalized planning ability is not unique to humans, and demonstrate that human-like language is not required for generalized planning skills. These findings also suggest that in addition to species niche specific cognitive abilities, generalized cognitive abilities may play an important role in the evolutionary success of some species.

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Tufted capuchin monkeys (Cebus apella), a species of New World primates, are known to be adept at various complex tool use both in the laboratory and in the wild. With their manual dexterity, they work as a helper for quadriplegic people. Social intelligence hypothesis, which places social intelligence as a major factor to advance complex information processing capability, predicts advanced social intelligence in this species with highly developed physical intelligence. In this paper, I describe a series of studies on social intelligence of this species in our comparative cognition laboratory at Kyoto University. As a competitive aspect of social intelligence, we analyzed spontaneous deceptive behavior between the monkeys. Two monkeys, dominant and subordinate, faced each other in the transparent boxes and two food cups were placed between them. When the subordinate monkey opened the baited cup, the dominant opponent was able to usurp the food. Some of the subordinates started to open the empty cup first: a behavior that could be interpreted as a deceptive act. As a cooperative aspect, we showed that two monkeys cooperated by dividing a sequence of behavior necessary to obtain rewards. This behavior continued even when only one of the participants received a reward if their roles were switched every trial; a reciprocal altruism was shown. To examine whether such complicated social behaviors reflect processes of mentalizing, we asked whether capuchin monkeys have cognitive components underlying them. We found that the monkeys are capable of recognizing attentional states of humans, inferring consequences of other's behavior, recognizing other's knowledge status, inferring the cause of other's emotional expression, and recognizing other's welfare. Thus these primitive aspects of mentalizing are clearly shared in species that is much more distant from humans than apes.

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Based on the Law for the Humane Treatment and Management of Animals, the Ministry of the Environment specifies “Standards Relating to the Care and Management of Laboratory Animals and Relief of Pain”. Regarding the use of laboratory animals, Japan has avoided stringent laws and regulations and adopted a system of rationalization based on voluntary management in each institution. These measures are intended to reinforce the independence of institutions to promote creative and flexible research. By legalization of the 3R-principle, ministries promoting science and technology have established basic policies for rationalization of animal experimentation in research institutions under their jurisdiction. The Science Council of Japan formulated the “Guidelines for Proper Conduct of Animal Experiments”. These guidelines were elaborated by collaboration of representatives from all scientific fields related to animal experiments including biological, pharmaceutical, agricultural, veterinary and medical sciences. To verify the voluntary management of laboratory animal care and use, 1) a collaborating committee of laboratory animal facilities of national, public and private universities, 2) Japan Health Sciences Foundation and 3) Japanese Society for Laboratory Animal Resources are investigating or testing third party evaluation systems, respectively. Accreditation by AAALAC International has been completed for seven facilities in Japan.

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This paper aims to reflect the 30 years of Ai project that started in 1978. Ai project started as a sort of ape-language project. However, it was uniquely different from the previous studies in terms of the computer-interfaced system and the introduction of psychophysical measurement. The original version of Ai project may be summarized as an attempt to know the perceptual world of a nonhuman animal. It combined the psychological studies on learning and perception and utilized the language-like skill as a window through which we can access to the chimpanzee mind. This paper put the Ai project in a historical context, summed up the research results, showed the fieldwork on the wild chimpanzees, and illuminated the establishment and the perspective of a new discipline named Comparative Cognitive Science.

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The effects of i.p. injections of the non-selective dopamine (DA) agonist apomorphine on open-field behavior were examined in high- (H) and low-activity (L) strains of mice selected for open-field activity. ICR mice used as a foundation population for selection were also included. In all strains, apomorphine (0.01, 0.1, and 1mg/kg) dose-dependently reduced ambulatory activity, defecation, locomotion, and leaning. Significant decreases were found at 0.1-1mg/kg compared to the vehicle control. The occurrence of grooming reached a peak in the second minute at 1mg/kg, whereas it gradually increased during testing at other doses and in the vehicle control. The strains showed different dose responses for stretching and rearing: significant reductions were detected only in L at 1mg/kg for stretching and only in ICR at 0.1-1mg/kg for rearing. These strain differences suggest that the DA systems were genetically modified during selection in both strains.

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Because of the decreasing number of individuals and the unsuccessful reproduction of captive gorillas, the documentation of the development of gorilla infants is attracting much attention in Japan. The aim of this study was to document the social development of a captive gorilla infant in Higashiyama Zoo. We recorded the activity budgets, proximity data, approach, and moving away of this infant, Ai, at 7 and 19 months of age, and the ways of infant-carrying at 19 months of age. In her first year, Ai started to be independent of her mother and to approach a nonkin female gorilla by herself. During the same period, the two ways of infant-carrying which gorilla infants display in different developmental stages were shown: carrying in the ventro-ventral position and ventro-dorsal position. These results revealed the developmental change of the relationship between Ai and each adult individual. The accumulation of case reports such as this study will help to understand the development of gorilla infants in captivity. Based on such understanding, the welfare and management of the captive gorilla population in Japan may be improved.

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