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: Abstract When living in a group, individuals have to make trade-offs, and compromise, in order to balance the advantages and disadvantages of group life. Strategies that enable individuals to achieve this typically affect inter-individual interactions resulting in nonrandom associations. Studying the patterns of this assortativity using social network analyses can allow us to explore how individual behavior influences what happens at the group, or population level. Understanding the consequences of these interactions at multiple scales may allow us to better understand the fitness implications for individuals. Social network analyses offer the tools to achieve this. This special issue aims to highlight the benefits of social network analysis for the study of primate behaviour, assessing it's suitability for analyzing individual social characteristics as well as group/population patterns. In this introduction to the special issue, we first introduce social network theory, then demonstrate with examples how social networks can influence individual and collective behaviors, and finally conclude with some outstanding questions for future primatological research. Am. J. Primatol. 73:703?719, 2011. ? 2011 Wiley-Liss, Inc.

Abstract: Equine welfare can be enhanced by applying species specific training. This may incorporate social learning, as horses are highly social and social stimuli are of primary importance. Social learning is comparable to individual learning in its learning mechanisms, differing primarily in the way it is stimulated. Our initial study showed that horses of different breeds (N = 38) follow humans after observing other horses doing so, but only if the observed horse was familiar to and higher ranking than the observer (Fisher's exact test: N = 12, P = 0.003). A second study showed that horses and ponies (N = 25) learned to pull a rope to open a feeding apparatus after observing demonstrations by conspecifics, again, only if the demonstrating horse was older and higher ranking than the observer (Fisher's combination test, N = 3, v2 = 27.71, p = 0.006). Our third approach showed that horses and ponies (N = 24) learned to press a switch to open a feeding apparatus after observing a familiar person (GzLM: N = 24, z = 2.33, P = 0.02). Most recently, we confronted horses and ponies (N = 50) with persons demonstrating different techniques for opening a feeding apparatus. In this study we investigated whether the horses would copy the demonstrators' techniques or apply their own. Here only some horses copied the technique, and most of the successful learners used their mouths irrespective of the demonstrators' postures (Chi Square Test: N = 40, df = 2, &#967;2 = 31.4, p < 0.001). In all the approaches social stimuli elicited learning processes in the test horses, while only a few individuals in the control groups mastered the tasks by individual learning. The following behaviour observed in the initial study may have been facilitated by a social stimuli (social facilitation), and the opening of the feed boxes in the subsequent studies appear to be mostly the result of enhancement (social enhancement). Some horses may have used the social stimuli at first and continued their learning process by individual trial and error. However, the horses were also selective in whom and some in how to copy. This may have been conditioned (socially conditioned) or the result of simple forms of reasoning on the reliability of the particular information provided by demonstrators of certain social ranks or social positions, as high ranking and familiar horses and familiar persons were copied and some imitated exactly.
Lay person message: Traditional riding instructions suggest that horses learn by observing other horses. For example, older, more experienced driving horses are used for initial training of young driving horses. We have shown that horses indeed use learning stimuli provided by other horse, as well as by humans. Horses readily accept stimuli observed in high ranking and familiar horses, and familiar persons. Such stimuli elicit learning processes which are comparable to individual learning. We suggest applying social learning whenever possible, as it is much faster and less stressful than individual learning, where learners experience negative outcomes in trial and error learning.

Abstract: Chapter 1 – Introduction, Pages 1-36
Chapter 2 – Perception, Pages 37-54
Chapter 3 – Behavior and the brain, Pages 55-84, Caroline Hahn
Chapter 4 – Learning, Pages 85-118
Chapter 5 – Social behavior, Pages 119-150
Chapter 6 – Communication, Pages 151-163
Chapter 7 – Locomotory behavior, Pages 165-187
Chapter 8 – Ingestive behavior, Pages 189-215
Chapter 9 – Eliminative behavior, Pages 217-221
Chapter 10 – Body care, Pages 223-243
Chapter 11 – Behavior of the stallion, Pages 245-264
Chapter 12 – Behavior of the mare, Pages 265-290
Chapter 13 – Training, Pages 291-311, Andrew McLean, Paul McGreevy
Chapter 14 – Handling and transport, Pages 313-329
Chapter 15 – Miscellaneous unwelcome behaviors, their causes and resolution, Pages 331-345
Further reading, Page 347
Glossary, Pages 351-356
Index, Pages 357-369

Abstract: Covers the aspects of social behaviour of animals in comprehensive form Provides a clear overview to up-to-date empirical and theoretical research on social animal behaviour
Discusses collective animal behaviour, social networks and animal personality in detail
The last decade has seen a surge of interest among biologists in a range of social animal phenomena, including collective behaviour and social networks. In ‘Animal Social Behaviour’, authors Ashley Ward and Michael Webster integrate the most up-to-date empirical and theoretical research to provide a new synthesis of the field, which is aimed at fellow researchers and postgraduate students on the topic. &#8203;