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Author Pongrácz, P.; Miklósi, Á.; Kubinyi, E.; Topál, J.; Csányi, V.
Title Interaction between individual experience and social learning in dogs Type Journal Article
Year 2003 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.
Volume 65 Issue 3 Pages 595-603
Keywords
Abstract We investigated the interaction between individual experience and social learning in domestic dogs,Canis familiaris . We conducted two experiments using detour tests, where an object or food was placed behind a transparent, V-shaped wire-mesh fence, such that the dogs could get the reward by going around the fence. In some groups, two open doors were offered as an alternative, easier way to reach the reward. In experiment 1 we opened the doors only in trial 1, then closed them for trials 2 and 3. In experiment 2 other dogs were first taught to detour the fence with closed doors after they had observed a detouring human demonstrator, then we opened the doors for three subsequent trials. In experiment 1 all dogs reached the reward by going through the doors in trial 1, but their detouring performance was poor after the doors had been closed, if they had to solve the task on their own. However, dogs in the experimental group that were allowed to watch a detouring human demonstrator after the doors had been closed showed improved detouring ability compared with those that did not receive a demonstration of detouring. In experiment 2 the dogs tended to keep on detouring along the fence even if the doors had been opened, giving up a chance to get behind the fence by a shorter route. These results show that dogs can use information gained by observing a human demonstrator to overcome their own mistakenly preferred solution in a problem situation. In a reversed situation social learning can also contribute to a preference for a less adaptive behaviour. However, only repeated individual and social experience leads to a durable manifestation of maladaptive behaviour. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour.
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Call Number refbase @ user @ Serial 565
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Author Hare, B.; Addessi, E.; Call, J.; Tomasello, M.; Visalberghi, E.
Title Do capuchin monkeys, Cebus apella, know what conspecifics do and do not see? Type Journal Article
Year 2003 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.
Volume 65 Issue 1 Pages 131-142
Keywords
Abstract Capuchin monkeys were tested in five experiments in which two individuals competed over food. When given a choice between retrieving a piece of food that was visible or hidden from the dominant, subordinate animals preferred to retrieve hidden food. This preference is consistent with the hypotheses that either (1) the subordinate knew what the dominant could and could not see or (2) the subordinate was monitoring the behaviour of the dominant and avoiding the piece of food that it approached. To test between these alternatives, we released subordinates with a slight head start forcing them to make their choice (between a piece of food hidden or visible to the dominant) before the dominant entered the area. Unlike chimpanzees, Pan troglodytes, subordinates that were given a head start did not preferentially approach hidden pieces of food first. Therefore, our experiments provide little support for the hypothesis that capuchin monkeys are sensitive to what another individual does or does not see. We compare our results with those obtained with chimpanzees in the same paradigm and discuss the evolution of primate social cognition. Copyright 2003 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.
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Notes Approved no
Call Number refbase @ user @ Serial 586
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Author Drent, P.J.; van Oers, K.; van Noordwijk, A.J.
Title Realized heritability of personalities in the great tit (Parus major) Type Journal Article
Year 2003 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci
Volume 270 Issue 1510 Pages 45-51
Keywords Aggression; Animals; Animals, Domestic; Animals, Wild; *Behavior, Animal; Breeding; Exploratory Behavior; Female; *Heredity; Male; Selection (Genetics); Songbirds/*genetics/*physiology; Variation (Genetics)
Abstract Behaviour under conditions of mild stress shows consistent patterns in all vertebrates: exploratory behaviour, boldness, aggressiveness covary in the same way. The existence of highly consistent individual variation in these behavioural strategies, also referred to as personalities or coping styles, allows us to measure the behaviour under standardized conditions on birds bred in captivity, link the standardized measurements to the behaviour under natural conditions and measure natural selection in the field. We have bred the great tit (Parus major), a classical model species for the study of behaviour under natural conditions, in captivity. Here, we report a realized heritability of 54 +/- 5% for early exploratory behaviour, based on four generations of bi-directional artificial selection. In addition to this, we measured hand-reared juveniles and their wild-caught parents in the laboratory. The heritability found in the mid-offspring-mid-parent regression was significantly different from zero. We have thus established the presence of considerable amounts of genetic variation for personality types in a wild bird.
Address Netherlands Institute of Ecology, PO Box 40, 6666 ZG Heteren, The Netherlands. drent@cto.nioo.knaw.nl
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Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title (down)
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ISSN 0962-8452 ISBN Medium
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Notes PMID:12590770 Approved no
Call Number refbase @ user @ Serial 591
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Author Nakamaru, M.; Sasaki, A.
Title Can transitive inference evolve in animals playing the hawk-dove game? Type Journal Article
Year 2003 Publication Journal of Theoretical Biology Abbreviated Journal J. Theor. Biol.
Volume 222 Issue 4 Pages 461-470
Keywords Hawk-dove game; Ess; Transitive inference; Resource holding potential
Abstract What should an individual do if there are no reliable cues to the strength of a competitor when fighting with it for resources? We herein examine the evolutionarily stable strategy (ESS) in the hawk-dove game, if the opponent's resource-holding potential (RHP) can only indirectly be inferred from the outcome of past interactions in the population. The strategies we examined include the classical mixed strategy in which no information on past games is utilized, the `imprinting' strategy in which a player increases/decreases its aggressiveness if it wins/loses a game, the `immediate inference' strategy in which a player can infer the strength of those opponents it fought before, and the `transitive inference' strategy in which a player can infer the strength of a new opponent through a third party with which both players have fought before. Invasibility analysis for each pair of strategies revealed that (i) the transitive-inference strategy can always invade the mixed strategy and the imprinting strategy, and itself refuses invasion by these strategies; (ii) the largest advantage for transitive inference is achieved when the number of games played per individual in one generation is small and when the cost of losing an escalated game is large; (iii) the immediate inference, rather than the transitive inference, can be an ESS if the cost of fighting is small; (iv) a strong linear ranking is established in the population of transitive-inference strategists, though it does not perfectly correlate to the ranking by actual RHPs. We found that the advantage of the transitive inference is not in its ability to correct a misassessment (it is actually the worst in doing so), but in the ability of quickly lining up either incorrect or correct assessments to form a linear dominance hierarchy.
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Call Number refbase @ user @ Serial 601
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Author McDonnell, S.M. (ed)
Title The Equid Ethogram: A Practical Field Guide to Horse Behavior Type Book Whole
Year 2003 Publication Abbreviated Journal
Volume Issue Pages
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Publisher Eclipse Press Place of Publication Lexington, Kentucky Editor McDonnell, S.M.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN ISBN 978-1581500905 Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 711
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Author Call, J.; Brauer, J.; Kaminski, J.; Tomasello, M.
Title Domestic dogs (Canis familiaris) are sensitive to the attentional state of humans Type Journal Article
Year 2003 Publication Journal of comparative psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol
Volume 117 Issue 3 Pages 257-263
Keywords Animals; *Appetitive Behavior; *Attention; *Bonding, Human-Pet; *Concept Formation; Cues; Dogs/*psychology; Female; Humans; *Inhibition (Psychology); Male; Nonverbal Communication
Abstract Twelve domestic dogs (Canis familiaris) were given a series of trials in which they were forbidden to take a piece of visible food. In some trials, the human continued to look at the dog throughout the trial (control condition), whereas in others, the human (a) left the room, (b) turned her back, (c) engaged in a distracting activity, or (d) closed her eyes. Dogs behaved in clearly different ways in most of the conditions in which the human did not watch them compared with the control condition, in which she did. In particular, when the human looked at them, dogs retrieved less food, approached it in a more indirect way, and sat (as opposed to laid down) more often than in the other conditions. Results are discussed in terms of domestic dogs' social-cognitive skills and their unique evolutionary and ontogenetic histories.
Address Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany. call@eva.mpg.de
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. : 1983 Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0735-7036 ISBN Medium
Area Expedition Conference
Notes PMID:14498801 Approved no
Call Number refbase @ user @ Serial 713
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Author Horowitz, A.C.
Title Do humans ape? Or do apes human? Imitation and intention in humans (Homo sapiens) and other animals Type Journal Article
Year 2003 Publication Journal of comparative psychology Abbreviated Journal J Comp Psychol
Volume 117 Issue 3 Pages 325-336
Keywords Adolescent; Adult; Animals; *Appetitive Behavior; Attention; Child, Preschool; Concept Formation; Female; Humans; *Imitative Behavior; Male; Motivation; Pan troglodytes/*psychology; *Problem Solving; *Psychomotor Performance; Reaction Time; Species Specificity
Abstract A. Whiten, D. M. Custance, J.-C. Gomez, P. Teixidor, and K. A. Bard (1996) tested chimpanzees' (Pan troglodytes) and human children's (Homo sapiens) skills at imitation with a 2-action test on an “artificial fruit.” Chimpanzees imitated to a restricted degree; children were more thoroughly imitative. Such results prompted some to assert that the difference in imitation indicates a difference in the subjects' understanding of the intentions of the demonstrator (M. Tomasello, 1996). In this experiment, 37 adult human subjects were tested with the artificial fruit. Far from being perfect imitators, the adults were less imitative than the children. These results cast doubt on the inference from imitative performance to an ability to understand others' intentions. The results also demonstrate how any test of imitation requires a control group and attention to the level of behavioral analysis.
Address Department of Cognitive Science, University of California, San Diego, CA, USA. ahorowitz@crl.ucsd.edu
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. : 1983 Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0735-7036 ISBN Medium
Area Expedition Conference
Notes PMID:14498809 Approved yes
Call Number refbase @ user @ Serial 736
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Author Wilson, D.A.; Stevenson, R.J.
Title The fundamental role of memory in olfactory perception Type Journal Article
Year 2003 Publication Trends in Neurosciences Abbreviated Journal Trends. Neurosci.
Volume 26 Issue 5 Pages 243-247
Keywords olfactory perception mammals
Abstract Current emphasis on odorant physiochemical features as the basis for perception largely ignores the synthetic and experience-dependent nature of olfaction. Olfaction is synthetic, as mammals have only limited ability to identify elements within even simple odor mixtures. Furthermore, olfaction is experience-bound, as exposure alone can significantly affect the extent to which stimuli can be discriminated. We propose that early analytical processing of odors is inaccessible at the behavioral level and that all odors are initially encoded as `objects' in the piriform cortex. Moreover, we suggest that odor perception is wholly dependent on the integrity of this memory system and that its loss severely impairs normal perception.
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Notes Approved no
Call Number refbase @ user @ Serial 795
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Author Pusey, A. E.; Packer, C.
Title The Ecology of relationships Type Book Chapter
Year 2003 Publication Behavioural Ecology Abbreviated Journal Behav. Ecol.
Volume Issue Pages 254 -283
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Publisher Blackwell Scientific Publication Place of Publication Oxford Editor Krebs, J.R.; Davis, N.B.;
Language Summary Language Original Title
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Call Number refbase @ user @ Serial 820
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Author Wasilewski A.
Title 'Friendship' in ungulates? – Sociopositive relationships between non-related herd members of the same species Type Manuscript
Year 2003 Publication Abbreviated Journal
Volume Issue Pages
Keywords
Abstract http://www.staff.uni-marburg.de/~z-phylog/wisstaff/wasi-sum.htm

Summary

* The quantitative study presented here demonstrates and verifies for ungulates the existence of social bonds, which in humans are termed 'friendships'. Whereas 'friendships' in non-human primates have become increasingly accepted over the past 30 years, their existence in non-primates remained as yet to be proved.

* The investigation was conducted on ungulates, because like primates the majority of their species are highly social; at the same time they are phylogenetically distant to the primates. To date, research into the social behaviour of ungulates in general, and of domestic species in particular, focuses predominantly on agonistic (socionegative) components, such as conflicts and resulting dominance hierarchies; sociopositive behaviours have been largely neglected.

As a consequence, previous evidence in favour of 'friendships' among ungulates remained largely anecdotal. Studies explicitly investigating sociopositive relationships among herd members are rare and typically confound bonds based on 'friendships' with reproductive relationships (kinship and sexually motivated bonds).

* Of each of the two large ungulate orders two species were investigated: horses and donkeys (Perissodactyla, Equidae) and sheep and cattle (Artiodactyla, Bovidae). The comparative, individual-based (and hence highly discriminative) longitudinal approach addressed all three levels of social organisation: associations, interactions and bond patterns within social units. Due to its systematic, quantitative, individual-based and comparatively broad design, this work may be considered to some degree a 'pioneering study'. As a consequence, a substantial amount of time and effort was required, particularly with respect to developing methods for the collection and analysis of data.

* Two reasons led to conducting this study on domestic ungulates: For farm animals information about who is related to whom is usually readily available, facilitating discrimination between friendship and kinship. Furthermore, successful proof of 'friendships' among ungulates would imply practical consequences for animal husbandry, since a social environment accommodating the animals' psychosocial needs is an essential prerequisite for their well-being (ethical reasons for animal protection) and ultimately results in higher productivity and hence economic efficiency (anthropocentric reasons for animal protection).

* Field research was conducted in England. Cattle and sheep were studied under commercial husbandry conditions, whereas appropriately large herds of horses and donkeys could only be found at a sanctuary.

* Two to three herds of each of the four species, namely cattle, sheep, donkeys and horses, comprising 11 to 60 members (average herd size approx. 25) were studied in two consecutive years (1996: 36 weeks, 1997: 28 weeks). The herds of cattle mainly consisted of subadult females, whereas those of the other species were predominantly composed of adults. Equids were kept in mixed-sex herds of mares and geldings (castrated males); the bachelor flocks of sheep consisted of 'intact' males (rams). The data presented here are based on 234 individuals and approximately 1500 hours of observation.

* Since even human social psychology provides neither a consistent definition nor a universally applicable terminology, it was necessary to establish a generally valid, precise definition of 'friendship'. Care was taken to exclude characteristics containing a bias as to the function of friendships (criteria were limited to those regarding contents and form). The definition contains all relevant criteria including those necessary for discrimination against alternative sociopositive relationships.



Friendship is defined as a voluntary, reciprocal, non-reproductive bond between individuals. It is primarily dyadic and carries a subjective value to both participants. Friendship is characterised by positive affect ('affection') and is expressed in a consistent inter-individual preference.

This definition is applicable to social relationships among both human and non-human animals, as well as interspecific relationships.

* Two types of parameters were used as indicators of 'friendship': frequency of spatial proximity (nearest neighbours; consistent neighbour preferences as a reflection of associations) and frequencies of different spontaneous as well as experimentally induced sociopositive interactions. For different reasons, of the four kinds of interactions (social grooming s.l., resting in physical contact, sharing limited feed, documenting behaviours s.l.) only grooming and feed sharing proved reliable.

* Aspects of the animals' spontaneous behaviour were recorded for all herds and in both years, whereas husbandry conditions demanded that complementary experiments be restricted to a few selected herds only. Data were collected using different Sampling and Recording Techniques, which were usually combined for maximum efficiency (e.g. Scan Sampling with nearest neighbour data, Ad libitum Sampling and Continuous Recording with sociopositive interactions).

* Data were subjected to an extensive statistical analysis. In addition to commonly used uni- and bivariate methods (Binomial and Chi-Square Goodness-of-Fit Tests, bivariate Correlations and Mantel Tests) a number of multivariate statistics were applied (Multidimensional Scaling, hierarchical Cluster Analysis, partial Correlations and multiple Mantel-Tests). Dyadic data are best represented as matrices; matrix data, however, pose the difficulty of partial interdependence, requiring Randomisation Tests (such as the one developed by Mantel) for their analysis. The complexity and amount of neighbour data required the development and optimisation of a 'customised' evaluation software (NENESYS = NEarest NEighbour SYstematic Standardisation programme) in close interdisciplinary cooperation with computer scientists and mathematicians.

* Seven different aspects of 'ungulate friendships' were addressed. The presented results differ in extent and depth.

1. Demonstration and verification of friendships in ungulates

2. Quantification of inter-individual preferences

3. Situation-specific aspects of these preferences

4. Dynamics and duration of friendships

5. Asymmetry within the relationships

6. Conditions enhancing friendships

7. Functions of animal friendships

* All four species expressed distinct inter-individual ('personal') preferences both for certain neighbours and for specific partners for sociopositive interactions. Endeavouring to present conservative and hence reliable assessments, only those neighbour preferences exceeding a threshold criterion were considered as associations. As the set-up of the study ensured that these associations met the criteria outlined in the definition of 'friendship' by excluding alternative bases for bonds (such as kinship and sexual motivation = reproductive relationships), the first explicit attempt at verifying the existence of friendship can be considered successful for all four species of ungulates examined. As a consequence, the concept of 'friendship' needs to be extended beyond the order of primates.

* Due to methodological reasons, the frequencies of interactions are only semi-quantitative and hence can be compared within herds only.

Frequencies of spatial proximity, on the other hand, provide a fully quantitative indicator, enabling direct comparisons across species, between different herds of the same species and between individuals. Due to the 'spatial limitations' of this thesis, it mainly focuses on inter-species comparisons.

With the exception of donkeys, the species could be arranged in sequence of increasing values of three parameters characterising their associative structure: maximum strength of association, maximum group size and proportion of herd members associated in distinct groups. Cattle showed the lowest values in all three parameters, sheep were intermediate, and horses reached the highest values. In these three species the strength of their associations was positively related to group size and the proportion of individuals associated in distinct groups. The donkeys did not fit this pattern: On the one hand, their association pattern comprised the lowest proportion of associated members and the smallest groups (pairs); on the other hand, these pairs exhibited very strong associations.

* Comparing inter-individual preferences across up to four different situations clear interspecific differences became evident. Some of these were greater between species of the same order than between orders.

The comparison of structures of association during grazing to those during resting, revealed two distinct patterns: Herds of horses and sheep flocks divided themselves into separate, usually mutually exclusive and independent groups and their associations corresponded greatly in both situations. Donkeys and cattle, on the other hand, formed diffuse, incomplete associative networks. The proportion of associations corresponding in both situations was far lower than in horses and sheep.

In all four species frequencies of social grooming s.l. (sheep are generally believed not to engage in social grooming, but see below) were compared to proximity frequencies during grazing and resting; and additionally to frequencies of feed sharing in the equid species.

Whereas horses restricted their sociopositive interactions entirely (grooming) or mostly (feed sharing) to members of their own group, cattle showed very little if any correspondence between partner preferences when grazing, resting and grooming. Donkeys spread their preferences widely across herd members, 'typically' approaching individuals for grooming with whom they were not associated during either grazing or resting. Considering their patterns of feed sharing, two different types of behaviour became evident: Pairs of donkeys that were closely associated during both grazing and resting, preferentially shared feed between them, whereas the remaining herd members did not discriminate between associates and non-associates when sharing feed. For sheep the findings of this study substantially increased the likelihood that unidirectional head rubbing and reciprocal cheek-to-cheek contact serve to strengthen 'personal' bonds and reduce tension – two functions generally attributed to social grooming. Both behaviours occurred mostly, but not exclusively, within groups of associated animals; these associations corresponded largely during grazing and resting.

* Results indicate that different types of social interactions and associations during different activities, respectively, may be particularly suited to initiate, consolidate and intensify friendships and occur particularly frequently during different phases of friendship formation and development. In horses, for instance, social grooming appears to some extent to be associated with the initiation of bonds, whereas resting in close proximity seems to strengthen newly formed relationships.

The longitudinal character of the study permitted to trace existing bonds over a maximum of 18 months. The duration of bonds in horses and sheep was comparable to findings of other authors for herds whose social networks resulted from a mixture of bonds based on both friendship and kinship; cattle relationships lasted shorter than described in the literature, while those in donkeys turned out to be approximately twice as long as had been documented to date.

* Aspects of asymmetry within dyadic relationships become particularly evident in grooming behaviours in bovids, which are typically performed unilaterally (social licking in cattle and head rubbing in sheep). Both behaviours can occur either spontaneously or as a consequence of solicitation.

* Addressing the question of factors potentially encouraging friendships, relationships between the degree of similarity with respect to some physical characteristics and nearest neighbour frequencies were found to be statistically significant. Cattle of similar age associated more closely, and horned rams preferred other individuals with horns as neighbours. The widely accepted preference of horses for associates of similar coat colour (and height) was not verified.

It remains to be decided whether (in addition to this preference for similar individuals) a preference based on complementary characteristics does exist.

* Following a critical review of the methodology employed, the benefits ungulates derive from friendships and possible applications for animal husbandry are discussed. Very little convincing evidence of a (direct) concrete, practical benefit was found. A psychological benefit in the form of social / emotional support, on the opposite, became highly probable.

Anecdotal evidence indicates, that situations causing a state of anxiety, may favour the initiation and intensification of friendships. Moreover, the study was able to statistically prove connection between (roughly) simultaneous introduction to a new herd (novel social environment) and persisting associations (as an indicator of friendships) in horses and sheep. These findings suggest that ungulate friendships provide a feeling of security. Social / emotional support among friends is predominantly given in a passive manner, e.g. in the form of – both literally and metaphorically – standing by a friend during conflicts with a third party, followed by social grooming with the friend. Social grooming has been shown by other authors to reduce physiological symptoms of stress. In addition, external signs of relaxation indicate a decrease in psychological tension. Hence, psychological support enhances the animal's physical health (and ultimately increases its biological fitness), providing an indirect practical benefit.

* Since all larger species of farm animals are highly social ungulates, the demonstration and verification of friendships implies consequences for husbandry practice. Intensive husbandry conditions are characterised by high animal densities, resulting in increased social stress, and grouping of animals of similar ages, which interferes with or prevents the formation and maintenance of bonds between kin. As friendships develop preferentially between individuals of similar age, they can be accommodated with relatively little effort when deciding about regrouping. The study presented here provides explicit recommendations to interested stockpersons on how to expeditiously and efficiently identify existing friendships and on which aspects to take into account when regrouping established herds or introducing new members.

* The different aspects of the study and their complex and often interwoven interrelations are condensed into a 'Regelkreismodell'. This model facilitates the generation of precise hypotheses for future research. Further detailed investigation into a variety of questions raised by this study seems in many ways promising and rewarding.

* The successful demonstration and verification of the existence of friendship in ungulates requires an extension of the 'concept of friendship' beyond the order of primates and encourages more detailed research into the bonding behaviour of other social vertebrates (e.g. elephants, dolphins, carnivores and also parrots).

* This extension demands a reinterpretation of some behaviours which so far have been unsatisfactorily or controversially classified, such as social head or horn rubbing in sheep, which has been mentioned occasionally, but received very little attention in the literature. Due to its occurrence during aggressive interactions, some authors consider horn or head rubbing to be agonistic. Others suppose the preorbital gland to play a significant role in this type of interaction and interpret head or horn rubbing as a 'respectful gesture' (adopting the dominant sheep's individual scent).

The study presents the first description of cheek-to-cheek contact in sheep. These cheek contacts are unequivocally sociopositive in nature. Since they are frequently associated with head rubbing, a third interpretation of head rubbing behaviour is offered by classifying both behaviours within the context of social grooming s.l.. More detailed examinations of these behaviours will be conducted as part of a research project into the evolution of the bovidae.
Address
Corporate Author Thesis Ph.D. thesis
Publisher University of Marburg Place of Publication Marburg Editor
Language German Summary Language Original Title
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 824
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