Abstract: Social relationships are essential for maintaining human mental health, yet little is known about the brain mechanisms involved in the development and maintenance of social bonds. Animal models are powerful tools for investigating the neurobiological mechanisms regulating the cognitive processes leading to the development of social relationships and for potentially extending our understanding of the human condition. In this review, we discuss the roles of the neuropeptides oxytocin and vasopressin in the regulation of social bonding as well as related social behaviors which culminate in the formation of social relationships in animal models. The formation of social bonds is a hierarchical process involving social motivation and approach, the processing of social stimuli and formation of social memories, and the social attachment itself. Oxytocin and vasopressin have been implicated in each of these processes. Specifically, these peptides facilitate social affiliation and parental nurturing behavior, are essential for social recognition in rodents, and are involved in the formation of selective mother-infant bonds in sheep and pair bonds in monogamous voles. The convergence of evidence from these animal studies makes oxytocin and vasopressin attractive candidates for the neural modulation of human social relationships as well as potential therapeutic targets for the treatment of psychiatric disorders associated with disruptions in social behavior, including autism.

Abstract: Intraspecific allometric calculations of the brain to body size relation revealed distinct differences between 127 (67; 60) ancestral wild cavies and 82 (37; 45) guinea pigs, their domesticated relatives. The dependency of both measures from one another remained the same in both animal groups but the brains of guinea pigs were by 14.22% smaller at any net body weight. Consistent with results in other species the domestication of Cavia aperea is also characterized by a decrease of brain size. Fresh tissue sizes of the five brain parts medulla oblongata, cerebellum, mesencephalon, diencephalon and telencephalon were determined for 6 cavies and 6 guinea pigs by the serial section method. Additionally the sizes of 16 endbrain structures and those of the optic tract, the lateral geniculate body and the cochlear nucleus were measured. Different decrease values resulted for all these structures concomitant with domestication as was calculated from the amount of total brain size decrease and average relative structure values in the wild as well as the domesticated brain. The size decrease of the entire telencephalon (-13.7%) was within the range of the mean overall reduction as similarly was the case for the total neocortex (-10.7%) whereas the total allocortex (-20.9%) clearly was more strongly affected. The size decrease of the olfactory bulb (-41.9%) was extreme and clearly higher than found for the secondary olfactory structures (around -11%). The primary nuclei of other sensory systems (vision, audition) were decreased to less extent (lateral geniculate: -18.1%; cochlear nucleus: -12.6%). Mass decreases of pure white matter parts were nearly twice as high in contrast to associated grey matter parts (neocortex white versus grey matter; tractus opticus versus lateral geniculate body). The relatively great decrease values found for the limbic structures hippocampus (-26.9%) and schizocortex (-25.9%) are especially notable since they are in good conformity with domestication effects in other mammalian species. The findings of this study are discussed with regard to results of similar investigations on wild and domesticated gerbils (Meriones unguiculatus), the encephalization of the wild form, the special and species-specific mode and duration of domestication and in connection with certain behavioral changes as resulted from comparative investigations in ethology, socio-biology, endocrinology and general physiology.

Abstract: The diet strategy of the wolf in Europe is reviewed on the basis of 74 basic and 14 additional literature
sources. The comparative analysis reveals clear dependence on the latitude (and, therefore, on the changing
environmental conditions) correlated with the wild ungulate abundance and diversity. Following a
geographic pattern, the wolf is specialised on different species of ungulates: moose and reindeer in Scandinavia,
red deer in Central and Eastern Europe and wild boar in Southern Europe. Where this large prey
is taken, the roe deer is hunted with almost the same frequency in every region. The wolf diet in Europe
shows two ecological adaptations formed by a complex of variables: 1. Wolves living in natural habitats
with abundance of wild ungulates feed mainly on wild prey. 2. In highly anthropogenic habitats, with low
abundance of wild prey, wolves feed on livestock (where husbandry of domestic animals is available) and
take also a lot of plant food, smaller prey (hares and rodents) and garbage food. The frequency of occurrence
of wild ungulates in the diet of wolves in North Europe varies from 54.0% in Belarus to 132.7% in
Poland, while that of livestock is in the range from 0.4% in Norway to 74.9% in Belarus. In South Europe,
the frequency of occurrence of wild prey varies from 0% in Italy and Spain to 136.0% in Italy, while of domestic
ungulates ranges between 0% and 100% in Spain. The low density or lack of wild prey triggers the
switch of the wolf diet to livestock, plant food (32.2-85% in Italy) or even garbage (up to 41.5% in Italy).

Abstract: We argue that the operational definition proposed by Ramsey et al. does not represent a significant improvement for students of innovation, because it is so restrictive that it might actually prevent the testing of hypotheses on the relationships between innovation, ecology, evolution, culture, and intelligence. To avoid tautological thinking, we need to use an operational definition that is taxonomically unbiased and neutral with respect to the hypotheses to be tested.

Abstract: Intraspecific interactions between individuals or groups of individuals of the same species are an important component of population dynamics. Interactions can be static, such as spatial overlap, or dynamic based on the interactions of movements, and can be mediated through communication, such as the deployment of scent marks. Interactions and their behavioural outcomes can be difficult to determine, especially for species that live at low densities. With the use of GPS collars we quantify both static and dynamic interactions between male cheetahs (Acinonyx jubatus) and the behavioural outcomes. The 99% home-ranges of males overlapped significantly while there was little overlap of the 50% home-ranges. Despite this overlap, male cheetahs rarely came into close proximity of one another, possibly because presence was communicated through frequent visits to marking posts. The minimum distance between individuals in a dyad ranged from 89m to 196m but the average proximity between individuals ranged from 17,145 ± 6,865m to 26,367 ± 11,288m. Possible interactions took place more frequently at night than by day and occurred mostly in the 50% home-range of one individual of a dyad or where cores of both individuals overlapped. After a possible encounter male cheetahs stayed in close proximity to each other for up to 6 hours, which could be the result of a territory defence strategy or the presence of a receptive female. We believe that one of the encounters between a singleton and a 5-male coalition resulted in the death of the singleton. Our results give new insights into cheetah interactions, which could help our understanding of ecological processes such as disease transmission.