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Collective motion from local attraction

Daniel Strömbom
2011 Journal of Theoretical Biology  
Many animal groups, for example schools of fish or flocks of birds, exhibit complex dynamic patterns while moving cohesively in the same direction. These flocking patterns have been studied using self-propelled particle models, most of which assume that collective motion arises from individuals aligning with their neighbours. Here, we propose a self-propelled particle model in which the only social force between individuals is attraction. We show that this model generates three different
more » ... swarms, undirected mills and moving aligned groups. By studying our model in the zero noise limit, we show how these phases depend on the relative strength of attraction and individual inertia. Moreover, by restricting the field of vision of the individuals and increasing the degree of noise in the system, we find that the groups generate both directed mills and three dynamically moving, 'rotating chain' structures. A rich diversity of patterns is generated by social attraction alone, which may provide insight into the dynamics of natural flocks.
doi:10.1016/j.jtbi.2011.05.019 pmid:21620861 fatcat:bonu66cp7rdxnhhihwz7ddndxy

Asynchrony promotes polarized collective motion in attraction based models [article]

Daniel Strömbom, Tasnia Hassan, W. Hunter Greis, Alice Antia
2017 arXiv   pre-print
Animal groups frequently move in a highly organized manner, as represented by flocks of birds and schools of fish. Despite being an everyday occurrence, we do not yet fully understand how this works. What type of social interactions between animals gives rise to the overall flock structure and behavior we observe? This question is often investigated using self-propelled particle models where particles represent the individual animals. These models differ in the social interactions used,
more » ... al particle properties, and various technical assumptions. One particular technical assumption relates to whether all particles update their headings and positions at exactly the same time (synchronous update) or not (asynchronous update). Here we investigate the causal effects of this assumption in a specific model and find that it has a dramatic impact. In particular, polarized groups do not form when synchronous update is used, but are always produced with asynchronous updates. We also show that full asynchrony is not required for polarized groups to form and quantify time to polarized group formation. Since many important models in the literature have been implemented with synchronous update only, we speculate that our understanding of these models, or rather the social interactions on which they are based, may be incomplete. Perhaps a range of previously unobserved dynamic phenomena will emerge if other potentially more realistic update schemes are chosen.
arXiv:1710.02484v1 fatcat:trtmq3vtovhifnzekdur2ls4qu

Bistability and Switching Behavior in Moving Animal Groups

Daniel Strömbom Strömbom, Lafayette College, Stephanie Nickerson, Catherine Futterman, Alyssa DiFazio, Cameron Costello, Kolbjørn Tunstrøm, Lafayette College, Lafayette College, Lafayette College, Lafayette College, Chalmers University of Technology
2022 Northeast Journal of Complex Systems  
iss1/1 DOI: 10.22191/nejcs/vol4/iss1/1 Northeast Journal of Complex Systems (NEJCS), Vol. 4, No. 1 [2022], Art. 1 https://orb.binghamton.edu/nejcs/vol4/iss1/1 DOI: 10.22191/nejcs/vol4/iss1/1 Strömbom  ...  Repository @ Binghamton (The ORB), 2022 Northeast Journal of Complex Systems (NEJCS), Vol. 4, No. 1 [2022], Art. 1 https://orb.binghamton.edu/nejcs/vol4/iss1/1 DOI: 10.22191/nejcs/vol4/iss1/1 Strömbom  ... 
doi:10.22191/nejcs/vol4/iss1/1 fatcat:sc37gpfwcbaktkl6cxbysxkezq

Anticipation induces polarized collective motion in attraction based models [article]

Daniel Strömbom, Alice Antia
2017 arXiv   pre-print
In most models of collective motion in animal groups each individual updates its heading based on the current positions and headings of its neighbors. Several authors have investigated the effects of including anticipation into models of this type, and have found that anticipation inhibits polarized collective motion in alignment based models and promotes milling and swarming in the one attraction-repulsion model studied. However, it was recently reported that polarized collective motion does
more » ... erge in an alignment based asynchronous lattice model with mutual anticipation. To our knowledge this is the only reported case where polarized collective motion has been observed in a model with anticipation. Here we show that including anticipation induces polarized collective motion in a synchronous, off lattice, attraction based model. This establishes that neither asynchrony, mutual anticipation nor motion restricted to a lattice environment are strict requirements for anticipation to promote polarized collective motion. In addition, unlike alignment based models the attraction based model used here does not produce any type of polarized collective motion in the absence of anticipation. Here anticipation is a direct polarization inducing mechanism. We believe that utilizing anticipation instead of frequently used alternatives such as explicit alignment terms, asynchronous updates and asymmetric interactions to generate polarized collective motion may be advantageous in some cases.
arXiv:1710.05692v2 fatcat:tfa3lb2pyve3hib343jgprqohe

Robot Collection and Transport of Objects: A Biomimetic Process

Daniel Strömbom, Andrew J. King
2018 Frontiers in Robotics and AI  
Figure 5ab , Strömbom et al., 2014) .  ...  The robot algorithm is an adapted version of Strömbom et al.'  ... 
doi:10.3389/frobt.2018.00048 pmid:33500933 pmcid:PMC7805832 fatcat:h6dus5vh45dkxfqbi45epf5wfm

Self-organized traffic via priority rules in leaf-cutting ants

Daniel Strömbom, Audrey Dussutour
2018 PLoS Computational Biology  
Ants, termites and humans often form well-organized and highly efficient trails between different locations. Yet the microscopic traffic rules responsible for this organization and efficiency are not fully understood. In previous experimental studies with leaf-cutting ants (Atta colombica), a set of local priority rules were isolated and it was proposed that these rules govern the temporal and spatial organization of the traffic on the trails. Here we introduce a model based on these priority
more » ... les to investigate whether they are sufficient to produce traffic similar to that observed in the experiments on both a narrow and a wider trail. We establish that the model is able to reproduce key characteristics of the traffic on the trails. In particular, we show that the proposed priority rules induce de-synchronization into clusters of inbound and outbound ants on a narrow trail, and that priority-type dependent segregated traffic emerges on a wider trail. Due to the generic nature of the proposed priority rules we speculate that they may be used to model traffic organization in a variety of other ant species.
doi:10.1371/journal.pcbi.1006523 pmid:30307942 pmcid:PMC6198993 fatcat:xbiu4b2qdje2dfya5vp7j73y4y

Attraction vs. Alignment as Drivers of Collective Motion

Daniel Strömbom, Grace Tulevech
2022 Frontiers in Applied Mathematics and Statistics  
Figure (A) is from [16] (CC-BY Strömbom), Figure (C) is from [17] (CC-BY Strömbom), and (B,D,E) have been adapted from these. FIGURE 2 | 2 FIGURE 2 | Burst-and-glide and burst-and-stop simulations.  ... 
doi:10.3389/fams.2021.717523 fatcat:eh4fzpvpivfnddwadnvwl37hha

Anticipation Induces Polarized Collective Motion in Attraction Based Models

Daniel Strömbom, Lafayette College, Alice Antia, Carleton College
2021 Northeast Journal of Complex Systems  
These figures have been adapted from Fig 2a in [4] (Strömbom CC-BY). of the groups that form for different values of c are displayed and their polarization and scaled size values specified.  ...  Conversely, if |A t i | > |K t Northeast Journal of Complex Systems (NEJCS), Vol. 3, No. 1 [2021], Art. 2 https://orb.binghamton.edu/nejcs/vol3/iss1/2 DOI: 10.22191/nejcs/vol3/iss1/2 Strömbom  ... 
doi:10.22191/nejcs/vol3/iss1/2 fatcat:w45ejrodenafdmmxycplxiwb3e

Human activity affects the perception of risk by mule deer

Mary V. Price, Evelyn H. Strombom, Daniel T. Blumstein
2014 Current Zoology  
Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus hemionus varied with distance from an area of concentrated human activity-a subalpine field station. An observer walked trails at various distances away from the station looking for deer. Upon encounter, the observer walked toward the focal animal and noted the distance at which it
more » ... alerted and directed its attention to the approaching human (Alert Distance; AD), and the distance at which it fled (Flight Initiation Distance; FID). AD and FID both increased nonlinearly with distance from the center of the field station, reaching plateaus around 250 m and 750 m, respectively. Deer also tended to flee by stotting or running, rather than by walking, when far from the station but they walked away when near the station. These results indicate that deer perceive lower risk near a focused area of human activity, and that vigilance and flight behaviors respond on somewhat different spatial scales. The concept of a spatial "human footprint" on behavior may be useful for understanding how human activities affect wildlife [Current Zoology 60 (6): 693-699, 2014].
doi:10.1093/czoolo/60.6.693 fatcat:rjt5ijfzrfdaxfgvdvwjie3q4a

Asynchrony induces polarization in attraction-based models of collective motion

Daniel Strömbom, Tasnia Hassan, W. Hunter Greis, Alice Antia
2019 Royal Society Open Science  
Animal groups frequently move in a highly organized manner, as represented by flocks of birds and schools of fish. Despite being an everyday occurrence, we do not fully understand how this works. In particular, what social interactions between animals give rise to the flock structures we observe? This question is often investigated using self-propelled particle models where particles represent the individual animals. These models differ in the social interactions used, individual particle
more » ... ties, and various technical assumptions. One particular technical assumption relates to whether all particles update their headings and positions at exactly the same time (synchronous update) or not (asynchronous update). Here, we investigate the causal effects of this assumption in an attraction-only model and find that it has a dramatic impact. Polarized groups do not form when synchronous update is used, but are produced with asynchronous update, and this phenomenon is robust with respect to variation in particle displacements and inclusion of noise. Given that many important models have been implemented with synchronous update only, we speculate that our understanding of the social interactions on which they are based may be incomplete. Perhaps previously unobserved phenomena will emerge if other potentially more realistic update schemes are used.
doi:10.1098/rsos.190381 pmid:31183154 pmcid:PMC6502356 fatcat:7qury626kbh65fcxznjqiarmfe

Simulating Irrational Human Behavior to Prevent Resource Depletion

Anna Sircova, Fariba Karimi, Evgeny N. Osin, Sungmin Lee, Petter Holme, Daniel Strömbom, Cheng-Yi Xia
2015 PLoS ONE  
In a situation with a limited common resource, cooperation between individuals sharing the resource is essential. However, people often act upon self-interest in irrational ways that threaten the long-term survival of the whole group. A lack of sustainable or environmentally responsible behavior is often observed. In this study, we examine how the maximization of benefits principle works in a wider social interactive context of personality preferences in order to gain a more realistic insight
more » ... to the evolution of cooperation. We used time perspective (TP), a concept reflecting individual differences in orientation towards past, present, or future, and relevant for making sustainable choices. We developed a personalitydriven agent-based model that explores the role of personality in the outcomes of social dilemmas and includes multiple facets of diversity: (1) The agents have different behavior strategies: individual differences derived by applying cluster analysis to survey data from 22 countries (N = 10,940) and resulting in 7 cross-cultural profiles of TP; (2) The non-uniform distribution of the types of agents across countries; (3) The diverse interactions between the agents; and (4) diverse responses to those interactions in a well-mixed population. As one of the results, we introduced an index of overall cooperation for each of the 22 countries, which was validated against cultural, economic, and sustainability indicators (HDI, dimensions of national culture, and Environment Performance Index). It was associated with higher human development, higher individualism, lower power distance, and better environmental performance. The findings illustrate how individual differences in TP can be simulated to predict the ways people in different countries solve the personal vs. common gain dilemma in the global limited-resource situation. This interdisciplinary approach to social simulation can be adopted to explain the possible causes of global environmental issues and to predict their possible outcomes.
doi:10.1371/journal.pone.0117612 pmid:25760635 pmcid:PMC4356575 fatcat:5h2gdubngngplhmwboq3cmbgdq

Multi-scale Inference of Interaction Rules in Animal Groups Using Bayesian Model Selection

Richard P. Mann, Andrea Perna, Daniel Strömbom, Roman Garnett, James E. Herbert-Read, David J. T. Sumpter, Ashley J. W. Ward, Olaf Sporns
2013 PLoS Computational Biology  
Inference of interaction rules of animals moving in groups usually relies on an analysis of large scale system behaviour. Models are tuned through repeated simulation until they match the observed behaviour. More recent work has used the fine scale motions of animals to validate and fit the rules of interaction of animals in groups. Here, we use a Bayesian methodology to compare a variety of models to the collective motion of glass prawns (Paratya australiensis). We show that these exhibit a
more » ... reotypical 'phase transition', whereby an increase in density leads to the onset of collective motion in one direction. We fit models to this data, which range from: a mean-field model where all prawns interact globally; to a spatial Markovian model where prawns are self-propelled particles influenced only by the current positions and directions of their neighbours; up to non-Markovian models where prawns have 'memory' of previous interactions, integrating their experiences over time when deciding to change behaviour. We show that the mean-field model fits the large scale behaviour of the system, but does not capture fine scale rules of interaction, which are primarily mediated by physical contact. Conversely, the Markovian self-propelled particle model captures the fine scale rules of interaction but fails to reproduce global dynamics. The most sophisticated model, the non-Markovian model, provides a good match to the data at both the fine scale and in terms of reproducing global dynamics. We conclude that prawns' movements are influenced by not just the current direction of nearby conspecifics, but also those encountered in the recent past. Given the simplicity of prawns as a study system our research suggests that self-propelled particle models of collective motion should, if they are to be realistic at multiple biological scales, include memory of previous interactions and other non-Markovian effects.
doi:10.1371/journal.pcbi.1002961 pmid:23555206 pmcid:PMC3605063 fatcat:daauniugavd47bouurshaxqe4a

Multi-scale Inference of Interaction Rules in Animal Groups Using Bayesian Model Selection

Richard P. Mann, Andrea Perna, Daniel Strömbom, Roman Garnett, James E. Herbert-Read, David J. T. Sumpter, Ashley J. W. Ward, Olaf Sporns
2012 PLoS Computational Biology  
Inference of interaction rules of animals moving in groups usually relies on an analysis of large scale system behaviour. Models are tuned through repeated simulation until they match the observed behaviour. More recent work has used the fine scale motions of animals to validate and fit the rules of interaction of animals in groups. Here, we use a Bayesian methodology to compare a variety of models to the collective motion of glass prawns (Paratya australiensis). We show that these exhibit a
more » ... reotypical 'phase transition', whereby an increase in density leads to the onset of collective motion in one direction. We fit models to this data, which range from: a mean-field model where all prawns interact globally; to a spatial Markovian model where prawns are self-propelled particles influenced only by the current positions and directions of their neighbours; up to non-Markovian models where prawns have 'memory' of previous interactions, integrating their experiences over time when deciding to change behaviour. We show that the mean-field model fits the large scale behaviour of the system, but does not capture fine scale rules of interaction, which are primarily mediated by physical contact. Conversely, the Markovian self-propelled particle model captures the fine scale rules of interaction but fails to reproduce global dynamics. The most sophisticated model, the non-Markovian model, provides a good match to the data at both the fine scale and in terms of reproducing global dynamics. We conclude that prawns' movements are influenced by not just the current direction of nearby conspecifics, but also those encountered in the recent past. Given the simplicity of prawns as a study system our research suggests that self-propelled particle models of collective motion should, if they are to be realistic at multiple biological scales, include memory of previous interactions and other non-Markovian effects.
doi:10.1371/journal.pcbi.1002308 pmid:22241970 pmcid:PMC3252267 fatcat:7klyf6yhebdangtvupdd4slmky

An Open-Label, Phase II Study of the Safety of Pirfenidone in Patients with Idiopathic Pulmonary Fibrosis (PIPF-002)

Mark H. Gotfried, Carlos E. Girod, Danielle Antin-Ozerkis, Tracy Burgess, Indiana Strombom, John L. Stauffer, Klaus-Uwe Kirchgaessler, Maria L. Padilla
2018 Pulmonary Therapy  
Strombom is an employee of Genentech, Inc. J. L. Stauffer s an employee of Genentech, Inc. K.-U. Kirchgaessler is an employee of F. Hoffmann-La Roche Ltd. Compliance with Ethics Guidelines.  ... 
doi:10.1007/s41030-018-0053-y pmid:32026243 pmcid:PMC6967037 fatcat:ywehcjwrm5el5il23e5ek4bcje

Correction to 'Proto-cooperation: group hunting sailfish improve hunting success by alternating attacks on grouping prey'

James E. Herbert-Read, Pawel Romanczuk, Stefan Krause, Daniel Strömbom, Pierre Couillaud, Paolo Domenici, Ralf H. J. M. Kurvers, Stefano Marras, John F. Steffensen, Alexander D. M. Wilson, Jens Krause
2016 Proceedings of the Royal Society of London. Biological Sciences  
There was a mismatch between the units reported for the base metabolic rate, c 0 , in figure 3c in [1] and the corresponding units in the main text and labels of figure 3a,b. Instead of the rate c 0 being shown in 1 per hour, the label of the x-axis in figure 1c was given in 1 per second. The corrected figure is shown below. None of the findings of the paper have altered.
doi:10.1098/rspb.2016.2586 pmid:28003459 pmcid:PMC5204177 fatcat:olszoi4xv5fg5bfuw2pfbgti3m
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