scholarly journals Initiation and spread of escape waves within animal groups

2015 ◽  
Vol 2 (4) ◽  
pp. 140355 ◽  
Author(s):  
James E. Herbert-Read ◽  
Jerome Buhl ◽  
Feng Hu ◽  
Ashley J. W. Ward ◽  
David J. T. Sumpter
Keyword(s):  
Natural Selection ◽  
Simulation Model ◽  
Entire Group ◽  
Centralized Control ◽  
Local Interactions ◽  
Animal Groups ◽  
Fish Schools ◽  
Group Members ◽  
Group Density ◽  
Transfer Of Information

The exceptional reactivity of animal collectives to predatory attacks is thought to be owing to rapid, but local, transfer of information between group members. These groups turn together in unison and produce escape waves. However, it is not clear how escape waves are created from local interactions, nor is it understood how these patterns are shaped by natural selection. By startling schools of fish with a simulated attack in an experimental arena, we demonstrate that changes in the direction and speed by a small percentage of individuals that detect the danger initiate an escape wave. This escape wave consists of a densely packed band of individuals that causes other school members to change direction. In the majority of cases, this wave passes through the entire group. We use a simulation model to demonstrate that this mechanism can, through local interactions alone, produce arbitrarily large escape waves. In the model, when we set the group density to that seen in real fish schools, we find that the risk to the members at the edge of the group is roughly equal to the risk of those within the group. Our experiments and modelling results provide a plausible explanation for how escape waves propagate in nature without centralized control.

scholarly journals Collective Apologies Moderate the Effects of Justice Concerns on Support for Collective Punishment

2017 ◽  
Vol 48 (4) ◽  
pp. 194-207
Author(s):  
Jacques Berent ◽  
Andrea Pereira ◽  
Juan M. Falomir-Pichastor
Keyword(s):  
The Other ◽  
Third Party ◽  
Entire Group ◽  
Group Members ◽  
Sense Of Justice ◽  
Collective Punishment

Abstract. Following an offense, various justice concerns arise, and people might support the punishment of the offender’s entire group to restore a sense of justice (even if the other group members are innocent). We hypothesized that support for collective punishment might increase along one’s justice concerns, and that such effect can be hindered by the group’s collective apologies. In three studies, third-party observers were presented with various cases of aggression and we measured (Study 1) or manipulated (Studies 2 and 3) their justice concerns. In all studies, the presence (vs. absence) of collective apologies was additionally manipulated. The results confirmed our hypothesis thereby increasing our knowledge of both the determinants of collective punishment and the potential effects of collective apologies.

scholarly journals Canadian Consensus Guidelines for the Management of Cytomegalovirus Disease in HIV/AIDS

2004 ◽  
Vol 15 (6) ◽  
pp. 327-335 ◽  
Author(s):  
Richard G Lalonde ◽  
Guy Bovivin ◽  
Jean Deschênes ◽  
William G Hodge ◽  
J Jill Hopkins ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Highly Active Antiretroviral Therapy ◽  
Care Physician ◽  
Entire Group ◽  
Expert Opinions ◽  
Highly Active ◽  
Consensus Group ◽  
Group Members ◽  
Cmv Disease ◽  
Hiv Aids

BACKGROUND: The management of HIV-infected patients with cytomegalovirus (CMV) disease has changed significantly with the availability of highly active antiretroviral therapy (HAART).OBJECTIVES: These updated guidelines are intended to provide practical help to physicians managing HIV-positive patients with or at risk for CMV disease.METHODS: The 10 members of the Canadian CMV Disease in HIV/AIDS Consensus Group were infectious disease specialists, a primary care physician and ophthalmologists with expertise in HIV and CMV infection. Financial support by Hoffmann-La Roche Canada Ltd was unrestricted, and was limited to travel expenses and honoraria. The consensus group met in June and October 2002. Key areas to be considered were identified, and group members selected, reviewed and presented relevant recent literature for their assigned section for the group's consideration. Evidence was assessed based on established criteria, which were expert opinions of the members. Draft documents were circulated to the entire group and modified until consensus was reached. The final guidelines represent the group's consensus agreement. The guidelines were approved by the Canadian Infectious Disease Society.RESULTS AND CONCLUSIONS: The guidelines address symptom monitoring, screening for early detection and prevention, and treatment using oral, intravenous and intraocular anti-CMV therapies in conjunction with HAART.

Comparing the Contribution of the Group to the Initial Idea in Progressive Idea Generation

2012 ◽  
Author(s):  
Bryan M. Blair ◽  
Katja Hölttä-Otto
Keyword(s):  
Statistical Analysis ◽  
Statistical Significance ◽  
Idea Generation ◽  
Peer Pressure ◽  
Entire Group ◽  
Innovative Products ◽  
Initial Idea ◽  
Group Members ◽  
Innovation Characteristics

Successful Idea Generation (IG) is more likely to lead to original and innovative products. It is usually recommended that idea generation is done in groups. Specifically, progressive idea generation methods, such as 6-3-5/C-Sketch, have been developed to gain from the benefits of group based ideation while being less subject to the peer pressure of a typical brainstorming session, where people can call out ideas simultaneously. In this study, we investigate the contributions that the group makes to the initial ideas in such progressive idea generation. Participants developed concepts for one of two products, namely alarm clocks or litter grabbers. Statistical analysis was used to compare the results of the initial ideas to the entire group for both products. Samples were rated at feature level using three metrics: originality, number of innovation characteristics hit, and feasibility. Results indicate that, in general, the originality and innovativeness of the initial concepts is improved by the rest of the group members. Non-original initial ideas were improved in all four sample groups. Highly original initial ideas also were improved in most cases. Feasibility was generally lowered, but not with statistical significance. Results from the perspective of particular product feature and innovation characteristic categories were varied; some more popular than others.

scholarly journals Eco-friendly packaging training for women farmers group to support digital marketing in Tawangargo Village, Malang Regency

2021 ◽  
Vol 6 (5) ◽  
pp. 849-855
Author(s):  
Rahayu Relawati ◽  
Bambang Yudi Ariadi ◽  
Anas Tain
Keyword(s):  
Environmentally Friendly ◽  
Monitoring And Evaluation ◽  
Women Farmers ◽  
Digital Marketing ◽  
Transfer Of Technology ◽  
Food And Beverage ◽  
Service Activity ◽  
Market Opportunities ◽  
Group Members ◽  
Transfer Of Information

Pro-environmental consumers act selectively in choosing products, including packaging. This is both a challenge and an opportunity for the women farmer groups in Tawangargo Village, which produce food and beverage products. The method of this service activity was training and mentoring, transfer of information, monitoring and evaluation. The results of the activity have opened the insights of the female farmer group members to use environmentally friendly packaging and build relationships with suppliers. Especially with the transfer of technology through digital marketing, it will open up wider market opportunities. In its development, the use of environmentally friendly packaging was still combined with conventional packaging to maintain an existing market. On the other hand, actively uploading products in the digital market has not been going well, so it requires further assistance.

scholarly journals Collective Motion in Human Crowds

2018 ◽  
Vol 27 (4) ◽  
pp. 232-240 ◽  
Author(s):  
William H. Warren
Keyword(s):  
Collective Behavior ◽  
Collective Motion ◽  
Local Level ◽  
Self Organization ◽  
Coherent Motion ◽  
Global Level ◽  
Crowd Behavior ◽  
Local Interactions ◽  
Fish Schools ◽  
Emergency Situations

The balletic motion of bird flocks, fish schools, and human crowds is believed to emerge from local interactions between individuals in a process of self-organization. The key to explaining such collective behavior thus lies in understanding these local interactions. After decades of theoretical modeling, experiments using virtual crowds and analysis of real crowd data are enabling us to decipher the “rules of engagement” governing these interactions. On the basis of such results, my students and I built a dynamical model of how a pedestrian aligns his or her motion with that of a neighbor and how these binary interactions are combined within a neighborhood of interaction. Computer simulations of the model generate coherent motion at the global level and reproduce individual trajectories at the local level. This approach has yielded the first experiment-driven, bottom-up model of collective motion, providing a basis for understanding more complex patterns of crowd behavior in both everyday and emergency situations.

scholarly journals The Game of Poker Chips, Dominoes and Survival

2021 ◽  
Vol 8 (14) ◽  
pp. 91-104
Author(s):  
Larry Goldstein
Keyword(s):  
Team Building ◽  
Management Training ◽  
Initial Distribution ◽  
Point Of View ◽  
Discrete Mathematics ◽  
Entire Group ◽  
Group Survival ◽  
Group Members ◽  
High Level ◽  
Training Exercises

Abstract The Game of Poker Chips, Dominoes and Survival fosters team building and high level cooperation in large groups, and is a tool applied in management training exercises. Each player, initially given two colored poker chips, is allowed to make exchanges with the game coordinator according to two rules, and must secure a domino before time is called in order to ‘survive’. Though the rules are simple, it is not evident by their form that the survival of the entire group requires that they cooperate at a high level. From the point of view of the game coordinator, the di culty of the game for the group can be controlled not only by the time limit, but also by the initial distribution of chips, in a way we make precise by a time complexity type argument. That analysis also provides insight into good strategies for group survival, those taking the least amount of time. In addition, coordinators may also want to be aware of when the game is ‘solvable’, that is, when their initial distribution of chips permits the survival of all group members if given su cient time to make exchanges. It turns out that the game is solvable if and only if the initial distribution contains seven chips that have one of two particular color distributions. In addition to being a lively game to play in management training or classroom settings, the analysis of the game after play can make for an engaging exercise in any discrete mathematics course to give a basic introduction to elements of game theory, logical reasoning, number theory and the computation of algorithmic complexities.

scholarly journals Ontogeny of collective behavior reveals a simple attraction rule

2017 ◽  
Vol 114 (9) ◽  
pp. 2295-2300 ◽  
Author(s):  
Robert C. Hinz ◽  
Gonzalo G. de Polavieja
Keyword(s):  
Animal Behavior ◽  
Danio Rerio ◽  
Collective Behavior ◽  
Centralized Control ◽  
Potential Significance ◽  
Fish Schools ◽  
Animal Development ◽  
Collective Animal Behavior ◽  
Moving Groups ◽  
Attraction Behavior

The striking patterns of collective animal behavior, including ant trails, bird flocks, and fish schools, can result from local interactions among animals without centralized control. Several of these rules of interaction have been proposed, but it has proven difficult to discriminate which ones are implemented in nature. As a method to better discriminate among interaction rules, we propose to follow the slow birth of a rule of interaction during animal development. Specifically, we followed the development of zebrafish, Danio rerio, and found that larvae turn toward each other from 7 days postfertilization and increase the intensity of interactions until 3 weeks. This developmental dataset allows testing the parameter-free predictions of a simple rule in which animals attract each other part of the time, with attraction defined as turning toward another animal chosen at random. This rule makes each individual likely move to a high density of conspecifics, and moving groups naturally emerge. Development of attraction strength corresponds to an increase in the time spent in attraction behavior. Adults were found to follow the same attraction rule, suggesting a potential significance for adults of other species.

scholarly journals Inclusive groups can avoid the tragedy of the commons

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Arend Hintze ◽  
Jochen Staudacher ◽  
Katja Gelhar ◽  
Alexander Pothmann ◽  
Juliana Rasch ◽  
...  
Keyword(s):  
Common Good ◽  
Tragedy Of The Commons ◽  
Entire Group ◽  
The Public ◽  
The Common Good ◽  
Costly Punishment ◽  
The Commons ◽  
Group Members ◽  
The Common ◽  
The Cost

AbstractThe public goods game is a famous example illustrating the tragedy of the commons (Hardin in Science 162:1243–1248, 1968). In this game cooperating individuals contribute to a pool, which in turn is distributed to all members of the group, including defectors who reap the same rewards as cooperators without having made a contribution before. The question is now, how to incentivize group members to all cooperate as it maximizes the common good. While costly punishment (Helbing et al. in New J Phys 12:083005, 2010) presents one such method, the cost of punishment still reduces the common good. The selfishness of the group members favors defectors. Here we show that including other members of the groups and sharing rewards with them can be another incentive for cooperation, avoiding the cost required for punishment. Further, we show how punishment and this form of inclusiveness interact. This work suggests that a redistribution similar to a basic income that is coupled to the economic success of the entire group could overcome the tragedy of the commons.

scholarly journals The visual coupling between neighbors explains 'flocking' in human crowds

2021 ◽  
Author(s):  
Gregory C. Dachner ◽  
Trenton D. Wirth ◽  
Emily Richmond ◽  
William H Warren
Keyword(s):  
Angular Velocity ◽  
Walking Speed ◽  
Collective Motion ◽  
Natural Consequence ◽  
Local Interactions ◽  
Physical Systems ◽  
Fish Schools ◽  
Visual Model ◽  
Visual Occlusion ◽  
Overhead View

Patterns of collective motion or 'flocking' in birds, fish schools, and human crowds are believed to emerge from local interactions between individuals. Most models of collective motion attribute these interactions to hypothetical rules or forces, often inspired by physical systems, and described from an overhead view. We develop a visual model of human flocking from an embedded view, based on optical variables that actually govern pedestrian interactions. Specifically, people control their walking speed and direction by canceling the average optical expansion and angular velocity of their neighbors, weighted by visual occlusion. We test the model by simulating data from experiments with virtual crowds and real human 'swarms'. The visual model outperforms our previous overhead model and explains basic properties of physics-inspired models: 'repulsion' forces reduce to canceling optical expansion, 'attraction' forces to canceling optical contraction, and 'alignment' to canceling the combination of expansion/contraction and angular velocity. Critically, the neighborhood of interaction follows from Euclid's Law of perspective and the geometry of occlusion. We conclude that the local interactions underlying human flocking are a natural consequence of the laws of optics. Similar principles may apply to collective motion in other species.

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