|   | 
Details
   web
Records
Author Leca, J.-B.; Gunst, N.; Thierry, B.; Petit, O.
Title Distributed leadership in semifree-ranging white-faced capuchin monkeys Type Journal Article
Year 2003 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.
Volume 66 Issue 6 Pages 1045-1052
Keywords
Abstract We investigated the initiation of group movements in white-faced capuchin monkeys, Cebus capucinus, with the aim of determining whether a single individual with high dominance status consistently leads movements or whether leadership is distributed between group members. The group studied was reared in semifree-ranging conditions. A multivariate analysis followed by univariate analyses demonstrated that leadership was not concentrated on a single individual in this species. All individuals could initiate a collective movement. Nearly half of group members regularly succeeded in recruiting at least three followers. Although both sexes had similar rates of start attempts, females succeeded more frequently than males. We found no significant effect of the dominance status on the percentage of successful attempts. The use of a slow speed, looking back towards the other group members, or trills by the initiator heightened the likelihood of success in group movement initiation. An initiator starting from a core position in a clumped group was more successful than one starting from an edge position in a clumped group or from a dispersed group. Furthermore, the probability of successful start attempts was higher when the group remained stationary for a long period. Leadership in white-faced capuchins appears to be distributed between group members rather than exclusively concentrated on high-ranking individuals. Copyright 2003 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial (up) 2028
Permanent link to this record
 

 
Author Meunier, H.; Leca, J.B.; Deneubourg, J.L.; Petit, O.
Title Group movement decisions in capuchin monkeys: the utility of an experimental study and a mathematical model to explore the relationship between individual and collective behaviours Type Journal Article
Year 2006 Publication Behaviour Abbreviated Journal Behaviour
Volume 143 Issue Pages 1511-1527
Keywords animal society – collective decision-making – primates – group movement – mathematical modeling
Abstract In primate groups, collective movements are typically described as processes dependent on leadership mechanisms. However, in some species, decision-making includes negotiations and distributed leadership. These facts suggest that simple underlying processes may explain certain decision mechanisms during collective movements. To study such processes, we have designed experiments on white-faced capuchin monkeys (Cebus capucinus) during which we provoked collective movements involving a binary choice. These experiments enabled us to analyse the spatial decisions of individuals in the group. We found that the underlying process includes anonymous mimetism, which means that each individual may influence all members of the group. To support this result, we created a mathematical model issued from our experimental data. A totally anonymous model does not fit perfectly with our experimental distribution. A more individualised model, which takes into account the specific behaviour of social peripheral individuals, revealed the validity of the mimetism hypothesis. Even though white-faced capuchins have complex cognitive abilities, a coexistence of anonymous and social mechanisms appears to influence their choice of direction during collective movements. The present approach may offer vital insights into the relationships between individual behaviours and their emergent collective acts.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial (up) 2066
Permanent link to this record
 

 
Author Bourjade, M.; Thierry, B.; Maumy, M.; Petit, O.
Title Decision-making in Przewalski horses (Equus ferus przewalskii) is driven by the ecological contexts of collective movements Type Journal Article
Year 2009 Publication Ethology Abbreviated Journal Ethology
Volume 115 Issue 4 Pages 321-330
Keywords
Abstract We addressed decision-making processes in the collective movements of

two groups of Przewalski horses (Equus ferus przewalskii) living in a semi

free-ranging population. We investigated whether different patterns of

group movement are related to certain ecological contexts (habitat use

and group activity) and analysed the possible decision-making processes

involved. We found two distinct patterns; ‘single-bout’ and ‘multiplebout’

movements occurred in both study groups. The movements were

defined by the occurrence of collective stops between bouts and differed

by their duration, distance covered and ecological context. For both

movements, we found that a preliminary period involving several horses

occurred before departure. In single-bout movements, all group members

rapidly joined the first moving horse, independently of the preliminary

period. In multiple-bout movements, however, the joining

process was longer; in particular when the number of decision-makers

and their pre-departure behaviour before departure increased. Multiplebout

movements were more often used by horses to switch habitats and

activities. This observation demonstrates that the horses need more time

to resolve motivational conflicts before these departures. We conclude

that decision-making in Przewalski horses is based on a shared consensus

process driven by ecological determinants.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial (up) 4801
Permanent link to this record
 

 
Author Sueur, C.; Petit, O.
Title Signals use by leaders in Macaca tonkeana and Macaca mulatta: group-mate recruitment and behaviour monitoring Type Journal Article
Year 2010 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 13 Issue 2 Pages 239-248
Keywords Decision-making – Collective movement – Intention – Macaque – Social style – Kinship
Abstract Abstract  Animals living in groups have to make consensus decisions and communicate with each other about the time, or the direction, in which to move. In some species, the process relies on the proposition of a single individual, i.e. a first individual suggests a movement and the other group members decide whether or not to join this individual. In Tonkean (Macaca tonkeana) and rhesus macaques (Macaca mulatta), it has been observed that this first individual displays specific signals at departure. In this paper, we aimed to explore the function of such behaviours, i.e. if these behaviours were recruitment signals or only cues about the motivation of the first departed individual. We carried out temporal analyses and studied the latencies of the first departed individual’s behaviours and of the joining of other group members. We also assessed whether the social style of a species in terms of dominance and kinship relationships influenced the patterns of signal emissions. We then analyzed how the first departed individual decided to make a pause or to stop it according to the identities of group members that joined the collective movement. Results showed that Tonkean macaques and rhesus macaques seemed to use back-glances to monitor the joining of other group members and pauses to recruit such individuals. This was especially the case for highly socially affiliated individuals in Tonkean macaques and kin-related individuals in rhesus macaques. Moreover, back-glances and pauses disappeared when such individuals joined the first departed individual. From these results, we suggested that such behaviour could be considered intentional. Such findings could not be highlighted without temporal analyses and accurate observations on primate groups in semi-free ranging conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial (up) 5117
Permanent link to this record
 

 
Author Sueur, C.; Petit, O.
Title Organization of Group Members at Departure Is Driven by Social Structure in Macaca Type Journal Article
Year 2008 Publication International Journal of Primatology Abbreviated Journal Int. J. Primatol.
Volume 29 Issue 4 Pages 1085-1098
Keywords dominance – kinship – Macaca tonkeana – M. mulatta – network metrics – order – movement
Abstract Abstract  Researchers have often explained order of progression of group members during joint movement in terms of the influence of ecological pressures but rarely that of social constraints. We studied the order of joining by group members to a movement in semifree-ranging macaques with contrasting social systems: 1 group of Tonkean macaques (Macaca tonkeana) and 1 group of rhesus macaques (M. mulatta). We used network metrics to understand roles and associations among individuals. The way the macaques joined a movement reflected the social differences between the species in terms of dominance and kinship. Old and dominant male rhesus macaques were more often at the front of the movement, contrary to the Tonkean macaques, which exhibited no specific order. Moreover, rhesus macaques preferred to join high-ranking or related individuals, whereas Tonkean macaques based associations during joining mostly on sexual relationships with a subgroup of peripheral males.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial (up) 5125
Permanent link to this record
 

 
Author Jacobs, A.; Maumy, M.; Petit, O.
Title The influence of social organisation on leadership in brown lemurs (Eulemur fulvus fulvus) in a controlled environment Type Journal Article
Year 2008 Publication Behavioural Processes Abbreviated Journal Behav. Process.
Volume 79 Issue 2 Pages 111-113
Keywords Animals; *Decision Making; Dominance-Subordination; *Exploratory Behavior; Female; Group Structure; *Leadership; Lemur/*psychology; Male; Sex Factors; *Social Environment
Abstract Studies on leadership during group movements in several lemur species showed that females were responsible for the travelling choices concerning time and direction. Interestingly, in these species females are dominant over males. We investigated the influence of social organisation upon leadership processes by studying a lemur species in which social organisation is characterized by the absence of female dominance: the brown lemur (Eulemur fulvus fulvus). The study was conducted on a semi-free ranging group of 11 individuals and the analysis performed on 69 group movements showed that all the individuals could initiate a group movement. In 34 cases, the whole group moved. There was no significant difference in the number of start attempts or in the number of group members involved from one initiator to another. Moreover, there was no effect of sex or age of the initiator on the number of individuals following it or on the speed of the joining process. Therefore, the leadership observed is widely distributed to all group members. These results support the hypothesis of an influence of social organisation upon the decision-making processes but still remain to be studied in a more relevant ecological context.
Address IPHC-DEPE, Equipe d'ethologie des primates, UMR 7178, Centre National de la Recherche Scientifique-Universite Louis Pasteur and Centre de Primatologie, Strasbourg, France
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0376-6357 ISBN Medium
Area Expedition Conference
Notes PMID:18586413 Approved no
Call Number Equine Behaviour @ team @ Serial (up) 5127
Permanent link to this record
 

 
Author Sueur, C.; Petit, O.
Title Shared or unshared consensus decision in macaques? Type Journal Article
Year 2008 Publication Behavioural Processes Abbreviated Journal Behav. Process.
Volume 78 Issue 1 Pages 84-92
Keywords Collective movement; Decision-making; Leadership; Social style
Abstract Members of a social group have to make collective decisions in order to synchronise their activities. In a shared consensus decision, all group members can take part in the decision whereas in an unshared consensus decision, one individual, usually a dominant member of the group, takes the decision for the rest of the group. It has been suggested that the type of decision-making of a species could be influenced by its social style. To investigate this further, we studied collective movements in two species with opposed social systems, the Tonkean macaque (Macaca tonkeana) and the rhesus macaque (Macaca mulatta). From our results, it appears that the decision to move is the result of the choices and actions of several individuals in both groups. However, this consensus decision involved nearly all group members in Tonkean macaques whereas dominant and old individuals took a prominent role in rhesus macaques. Thus, we suggest that Tonkean macaques display equally shared consensus decisions to move, whereas in the same context rhesus macaque exhibit partially shared consensus decisions. Such a difference in making a collective decision might be linked to the different social systems of the two studied species.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0376-6357 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial (up) 5129
Permanent link to this record
 

 
Author Petit, O.; Bon, R.
Title Decision-making processes: The case of collective movements Type Journal Article
Year 2010 Publication Behavioural Processes Abbreviated Journal Behav. Process.
Volume 84 Issue 3 Pages 635-647
Keywords Consensus; Inter-individual relationships; Leadership; Self-organization; Social status
Abstract Besides focusing on the adaptive significance of collective movements, it is crucial to study the mechanisms and dynamics of decision-making processes at the individual level underlying the higher-scale collective movements. It is now commonly admitted that collective decisions emerge from interactions between individuals, but how individual decisions are taken, i.e. how far they are modulated by the behaviour of other group members, is an under-investigated question. Classically, collective movements are viewed as the outcome of one individual's initiation (the leader) for departure, by which all or some of the other group members abide. Individuals assuming leadership have often been considered to hold a specific social status. This hierarchical or centralized control model has been challenged by recent theoretical and experimental findings, suggesting that leadership can be more distributed. Moreover, self-organized processes can account for collective movements in many different species, even in those that are characterized by high cognitive complexity. In this review, we point out that decision-making for moving collectively can be reached by a combination of different rules, i.e. individualized (based on inter-individual differences in physiology, energetic state, social status, etc.) and self-organized (based on simple response) ones for any species, context and group size.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0376-6357 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial (up) 5217
Permanent link to this record
 

 
Author Petit, O.; Thierry, B.
Title Aggressive and peaceful interventions in conflicts in Tonkean macaques Type Journal Article
Year 1994 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.
Volume 48 Issue 6 Pages 1427-1436
Keywords
Abstract Abstract. Peaceful interventions in conflicts are an extremely rare phenomenon in most primate species. In contrast to aggressive interventions, they cannot lead to gains in terms of competition. To clarify the function and origin of this behaviour, the patterning and consequences of peaceful and aggressive interventions were studied in a semi-free ranging group of tonkean macaques, Macaca tonkeana. Intense conflicts frequently elicited both types of intervention. Interveners preferentially targeted the initiator of the conflict, who was generally the dominant of the two opponents. Males tended to intervene more than females, especially using peaceful interventions. Interventions were frequently performed on behalf of the most closely kin-related opponent; this was true particularly for aggressive interventions. In peaceful interventions, the intervener was usually dominant over both parties. Lipsmacking, clasping, mounting and social play were mainly used, and were successful in halting aggression. Peaceful interventions were frequently followed by an affinitive interaction, such as grooming, between intervener and target. Peaceful interventions thus appear to protect the beneficiary while preserving the social relationship between intervener and target. The origin of the behaviour can be traced to the epigenetic constraints arising from the species-specific social organization.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-3472 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial (up) 5244
Permanent link to this record
 

 
Author Ramseyer, A.; Petit, O.; Thierry, B.
Title Decision-making in group departures of female domestic geese Type Journal Article
Year 2009 Publication Behaviour Abbreviated Journal Behaviour
Volume 146 Issue Pages 351-371
Keywords MOVEMENT; COLLECTIVE; PRE-DEPARTURE; RECRUITMENT; ANSER DOMESTICUS
Abstract Group-living animals have to make trade-offs to reach consensus and travel together. We investigated the recruitment processes underpinning decision-making at departure in a group of 20 female domestic geese (Anser domesticus) kept in semi-free-range conditions. Two observers continuously videotaped the behaviours of the birds. Data were analyzed using multiple regression analyses. We found that decision-making was a continuous and distributed process. Departure was preceded by an increase in the arousal state of group members and their initial orientation influenced recruitment. Patterns of group movement could be predicted from the behaviours of individuals before departure. Individuals' locations, moves and signals could act as passive or communicative cues. A higher number of vocalisations and arousal behaviours led to a larger number of individuals recruited. Some individuals were more efficient than others in recruiting followers but any geese could initiate a movement. First movers recruited a higher number of mates when they had a greater number of neighbours. Not only the first mover but also the behaviours of the second and third movers prompted further individuals to follow. There was no evidence that geese were able to intentionally recruit others, rather they synchronized and adjusted each other's motives until reaching a consensus.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial (up) 5289
Permanent link to this record