scholarly journals Using activity and sociability to characterize collective motion

2018 ◽  
Vol 373 (1746) ◽  
pp. 20170015 ◽  
Author(s):  
David J. T. Sumpter ◽  
Alex Szorkovszky ◽  
Alexander Kotrschal ◽  
Niclas Kolm ◽  
James E. Herbert-Read
Keyword(s):  
Poecilia Reticulata ◽  
Collective Motion ◽  
Movement Ecology ◽  
Simulation Studies ◽  
Evolutionary Perspective ◽  
Theme Issue ◽  
Directed Movement ◽  
Wide Range ◽  
Group Members ◽  
Main Factors

A wide range of measurements can be made on the collective motion of groups, and the movement of individuals within them. These include, but are not limited to: group size, polarization, speed, turning speed, speed or directional correlations, and distances to near neighbours. From an ecological and evolutionary perspective, we would like to know which of these measurements capture biologically meaningful aspects of an animal's behaviour and contribute to its survival chances. Previous simulation studies have emphasized two main factors shaping individuals' behaviour in groups; attraction and alignment. Alignment responses appear to be important in transferring information between group members and providing synergistic benefits to group members. Likewise, attraction to conspecifics is thought to provide benefits through, for example, selfish herding. Here, we use a factor analysis on a wide range of simple measurements to identify two main axes of collective motion in guppies ( Poecilia reticulata ): (i) sociability, which corresponds to attraction (and to a lesser degree alignment) to neighbours, and (ii) activity, which combines alignment with directed movement. We show that for guppies, predation in a natural environment produces higher degrees of sociability and (in females) lower degrees of activity, while female guppies sorted for higher degrees of collective alignment have higher degrees of both sociability and activity. We suggest that the activity and sociability axes provide a useful framework for measuring the behaviour of animals in groups, allowing the comparison of individual and collective behaviours within and between species. This article is part of the theme issue ‘Collective movement ecology’.

scholarly journals Introduction to redundancy rules: the continuous wavelet transform comes of age

2018 ◽  
Vol 376 (2126) ◽  
pp. 20170258 ◽  
Author(s):  
Paul S. Addison
Keyword(s):  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
State Of The Art ◽  
Structural Characteristics ◽  
Continuous Wavelet ◽  
Theme Issue ◽  
Current State ◽  
Analysis Methods ◽  
Wide Range ◽  
New Form

Redundancy: it is a word heavy with connotations of lacking usefulness. I often hear that the rationale for not using the continuous wavelet transform (CWT)—even when it appears most appropriate for the problem at hand—is that it is ‘redundant’. Sometimes the conversation ends there, as if self-explanatory. However, in the context of the CWT, ‘redundant’ is not a pejorative term, it simply refers to a less compact form used to represent the information within the signal. The benefit of this new form—the CWT—is that it allows for intricate structural characteristics of the signal information to be made manifest within the transform space, where it can be more amenable to study: resolution over redundancy. Once the signal information is in CWT form, a range of powerful analysis methods can then be employed for its extraction, interpretation and/or manipulation. This theme issue is intended to provide the reader with an overview of the current state of the art of CWT analysis methods from across a wide range of numerate disciplines, including fluid dynamics, structural mechanics, geophysics, medicine, astronomy and finance. This article is part of the theme issue ‘Redundancy rules: the continuous wavelet transform comes of age’.

scholarly journals An Analysis of Heterogeneity in German Speaking Birdwatchers Reveals Three Distinct Clusters and Gender Differences

Birds ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 250-260
Author(s):  
Christoph Randler
Keyword(s):  
Cluster Analysis ◽  
Optimal Solution ◽  
Social Bonding ◽  
Cluster Solution ◽  
Novice Group ◽  
Wide Range ◽  
German Speaking ◽  
Group Members ◽  
Bird Group ◽  
And Gender

The purpose of this study was to segment birdwatchers into clusters. Members from a wide range of bird related organizations, from highly specialized birders as well as Facebook bird group members were studied to provide a diverse dataset (n = 2766; 50.5% men). Birding specialization was measured with a battery of questionnaires. Birding specialization encompassed the three constructs of skill/competence, behavior, personal and behavioral commitment. Additionally, involvement, measured by centrality to lifestyle, attraction, social bonding, and identity, was used. The NbClust analyses showed that a three-cluster solution was the optimal solution. Then, k-means cluster analysis was applied on three groups: casual/novice, intermediate, and specialist/advanced birdwatchers. More men than women were in the specialist/advanced group and more women than men in the casual/novice group. As a conclusion, this study confirms a three-cluster solution for segmenting German birdwatchers based on a large and diverse sample and a broad conceptualization of the construct birding specialization. These data can be used to address different target audiences (novices, advanced birders) with different programs, e.g., in nature conservation.

scholarly journals Psychology, Meaning Making, and the Study of Worldviews

2018 ◽  
Author(s):  
Ann Taves ◽  
Egil Asprem ◽  
Elliott Daniel Ihm
Keyword(s):  
Meaning Making ◽  
Sense Making ◽  
Evolutionary Perspective ◽  
Cognitive Level ◽  
Multidisciplinary Study ◽  
Human Ability ◽  
Wide Range ◽  
Object Of Study ◽  
Different Levels ◽  
Ways Of Life

To get beyond the solely negative identities signaled by atheism and agnosticism, we have to conceptualize an object of study that includes religions and non-religions. We advocate a shift from “religions” to “worldviews” and define worldviews in terms of the human ability to ask and reflect on “big questions” ([BQs], e.g., what exists? how should we live?). From a worldviews perspective, atheism, agnosticism, and theism are competing claims about one feature of reality and can be combined with various answers to the BQs to generate a wide range of worldviews. To lay a foundation for the multidisciplinary study of worldviews that includes psychology and other sciences, we ground them in humans’ evolved world-making capacities. Conceptualizing worldviews in this way allows us to identify, refine, and connect concepts that are appropriate to different levels of analysis. We argue that the language of enacted and articulated worldviews (for humans) and world-making and ways of life (for humans and other animals) is appropriate at the level of persons or organisms and the language of sense making, schemas, and meaning frameworks is appropriate at the cognitive level (for humans and other animals). Viewing the meaning making processes that enable humans to generate worldviews from an evolutionary perspective allows us to raise news questions for psychology with particular relevance for the study of nonreligious worldviews.

Agricultural Aviation

1960 ◽  
Vol 64 (590) ◽  
pp. 87-92
Author(s):  
A. H. Wheeler
Keyword(s):  
Second World War ◽  
Chemical Forms ◽  
World War ◽  
The Past ◽  
Wide Range ◽  
Agricultural Chemistry ◽  
The World ◽  
General Improvement ◽  
Main Factors ◽  
Second World

The first International Agricultural Aviation Conference, held at the College of Aeronautics at Cranfield between the 15th and 18th of September 1959, was well timed to mark one stage in the development of the art of airborne farming—it was the stage when the art ceased to be mainly experimental and became essentially a commercial business.Intermittently for the past thirty years, in various parts of the world, attempts have been made with varying degrees of economic and practical success to do certain operations connected with farming, forestry or other allied activities. Two main factors within the past decade have served to intensify the interest and activity in the art. One important factor is the general improvement in aircraft, including helicopters, coupled with the very large number of relatively suitable ones which became redundant (and therefore cheap) at the end of the Second World War. The other factor, equal in importance, concerns the development of the science of agricultural chemistry which has given the farmer a new and wide range of fertilisers, selective weed killers and other chemical forms of pest control which are effective in reasonably small bulk.

scholarly journals Rheology of magnetic colloids containing clusters of particle platelets and polymer nanofibres

2020 ◽  
Vol 378 (2171) ◽  
pp. 20190255 ◽  
Author(s):  
Mariem Mekni Abrougui ◽  
Ezzeddine Srasra ◽  
Modesto T. Lopez-Lopez ◽  
Juan D. G. Duran
Keyword(s):  
Magnetic Fields ◽  
Magnetic Particles ◽  
Polymer Network ◽  
Soft Materials ◽  
Design Parameters ◽  
Heterogeneous Structure ◽  
High Porosity ◽  
Theme Issue ◽  
Wide Range ◽  
Magnetorheological Effect

Magnetic hydrogels (ferrogels) are soft materials with a wide range of applications, especially in biomedicine because (i) they can be provided with the required biocompatibility; (ii) their heterogeneous structure allows their use as scaffolds for tissue engineering; (iii) their mechanical properties can be modified by changing different design parameters or by the action of magnetic fields. These characteristics confer them unique properties for acting as patterns that mimic the architecture of biological systems. In addition, and (iv) given their high porosity and aqueous content, ferrogels can be loaded with drugs and guided towards specific targets for local (non-systemic) pharmaceutical treatments. The ferrogels prepared in this work contain magnetic particles obtained by precipitation of magnetite nanoparticles onto the porous surface of bentonite platelets. Then, the particles were functionalized by adsorption of alginate molecules and dispersed in an aqueous solution of sodium alginate. Finally, the gelation was promoted by cross-linking the alginate molecules with Ca 2+ ions. The viscoelastic properties of the ferrogels were measured in the absence/presence of external magnetic fields, showing that these ferrogels exhibited a strong enough magnetorheological effect. This behaviour is explained considering the field-induced strengthening of the heterogeneous (particle–polymer) network generated inside the ferrogel. This article is part of the theme issue ‘Patterns in soft and biological matters'.

scholarly journals Watch me, watch you: ritual participation increases in-group displays and out-group monitoring in children

2020 ◽  
Vol 375 (1805) ◽  
pp. 20190437 ◽  
Author(s):  
Nicole J. Wen ◽  
Aiyana K. Willard ◽  
Michaela Caughy ◽  
Cristine H. Legare
Keyword(s):  
Social Group ◽  
Control Task ◽  
Theme Issue ◽  
Social Functions ◽  
Time Points ◽  
Group Members ◽  
Group Monitoring

Collective rituals serve social functions for the groups that perform them, including identifying group members and signalling group commitment. A novel social group paradigm was used in an afterschool programme ( N = 60 4–11-year-olds) to test the influence of participating in a ritual task on in-group displays and out-group monitoring over repeated exposures to the group. The results demonstrate that ritual participation increases in-group displays (i.e. time spent displaying materials to in-group members) and out-group monitoring (i.e. time spent looking at out-group members) compared with a control task across three time points. This study provides evidence for the processes by which rituals may influence children's behaviours towards in- and out-group members and discusses implications for understanding the development of ritual cognition and behaviour. This article is part of the theme issue ‘Ritual renaissance: new insights into the most human of behaviours’.

scholarly journals Translating surveillance data into incidence estimates

2019 ◽  
Vol 374 (1776) ◽  
pp. 20180262 ◽  
Author(s):  
Y. Bourhis ◽  
T. Gottwald ◽  
F. van den Bosch
Keyword(s):  
Infectious Disease ◽  
Disease Incidence ◽  
Disease Outbreaks ◽  
Estimation Methods ◽  
Estimation Model ◽  
Theme Issue ◽  
Online Application ◽  
Infectious Disease Outbreaks ◽  
Sampling Series ◽  
Wide Range

Monitoring a population for a disease requires the hosts to be sampled and tested for the pathogen. This results in sampling series from which we may estimate the disease incidence, i.e. the proportion of hosts infected. Existing estimation methods assume that disease incidence does not change between monitoring rounds, resulting in an underestimation of the disease incidence. In this paper, we develop an incidence estimation model accounting for epidemic growth with monitoring rounds that sample varying incidence. We also show how to accommodate the asymptomatic period that is the characteristic of most diseases. For practical use, we produce an approximation of the model, which is subsequently shown to be accurate for relevant epidemic and sampling parameters. Both the approximation and the full model are applied to stochastic spatial simulations of epidemics. The results prove their consistency for a very wide range of situations. The estimation model is made available as an online application. This article is part of the theme issue ‘Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control’. This theme issue is linked with the earlier issue ‘Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes’.

scholarly journals The myriad challenges of the Paris Agreement

2018 ◽  
Vol 376 (2119) ◽  
pp. 20180066 ◽  
Author(s):  
Dann Mitchell ◽  
Myles R. Allen ◽  
Jim W. Hall ◽  
Benito Muller ◽  
Lavanya Rajamani ◽  
...  
Keyword(s):  
Paris Agreement ◽  
Original Research ◽  
Theme Issue ◽  
25Th Anniversary ◽  
Social Challenges ◽  
Wide Range ◽  
Science Community ◽  
Warming World ◽  
The University

The much awaited and intensely negotiated Paris Agreement was adopted on 12 December 2015 by the Parties to the United Nations Framework Convention on Climate Change. The agreement set out a more ambitious long-term temperature goal than many had anticipated, implying more stringent emissions reductions that have been under-explored by the research community. By its very nature a multidisciplinary challenge, filling the knowledge gap requires not only climate scientists, but the whole Earth system science community, as well as economists, engineers, lawyers, philosophers, politicians, emergency planners and others to step up. To kick start cross-disciplinary discussions, the University of Oxford's Environmental Change Institute focused its 25th anniversary conference upon meeting the challenges of the Paris Agreement for science and society. This theme issue consists of review papers, opinion pieces and original research from some of the presentations within that meeting, covering a wide range of issues underpinning the Paris Agreement. This article is part of the theme issue ‘The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.

scholarly journals Conformity in the collective: differences in hunger affect individual and group behavior in a shoaling fish

2019 ◽  
Vol 30 (4) ◽  
pp. 968-974 ◽  
Author(s):  
Alexander D M Wilson ◽  
Alicia L J Burns ◽  
Emanuele Crosato ◽  
Joseph Lizier ◽  
Mikhail Prokopenko ◽  
...  
Keyword(s):  
Collective Behavior ◽  
Nearest Neighbor ◽  
Collective Motion ◽  
Internal State ◽  
Group Behavior ◽  
Fundamental Interest ◽  
Individual Level ◽  
Group Members ◽  
The Individual ◽  
Nearest Neighbor Distances

Abstract Animal groups are often composed of individuals that vary according to behavioral, morphological, and internal state parameters. Understanding the importance of such individual-level heterogeneity to the establishment and maintenance of coherent group responses is of fundamental interest in collective behavior. We examined the influence of hunger on the individual and collective behavior of groups of shoaling fish, x-ray tetras (Pristella maxillaris). Fish were assigned to one of two nutritional states, satiated or hungry, and then allocated to 5 treatments that represented different ratios of satiated to hungry individuals (8 hungry, 8 satiated, 4:4 hungry:satiated, 2:6 hungry:satiated, 6:2 hungry:satiated). Our data show that groups with a greater proportion of hungry fish swam faster and exhibited greater nearest neighbor distances. Within groups, however, there was no difference in the swimming speeds of hungry versus well-fed fish, suggesting that group members conform and adapt their swimming speed according to the overall composition of the group. We also found significant differences in mean group transfer entropy, suggesting stronger patterns of information flow in groups comprising all, or a majority of, hungry individuals. In contrast, we did not observe differences in polarization, a measure of group alignment, within groups across treatments. Taken together these results demonstrate that the nutritional state of animals within social groups impacts both individual and group behavior, and that members of heterogenous groups can adapt their behavior to facilitate coherent collective motion.

scholarly journals Contrasts in kinship structure in mammalian societies

2020 ◽  
Vol 31 (4) ◽  
pp. 971-977 ◽  
Author(s):  
Mark Dyble ◽  
Tim H Clutton-Brock
Keyword(s):  
Social Groups ◽  
Theoretical Models ◽  
Competitive Behavior ◽  
Factors Affecting ◽  
Interspecific Differences ◽  
Wide Range ◽  
Group Members ◽  
Relative Rarity ◽  
Kinship Structure ◽  
Insight Into

Abstract Comparative studies of mammals confirm Hamilton’s prediction that differences in cooperative and competitive behavior across species will be related to contrasts in kinship between group members. Although theoretical models have explored the factors affecting kinship within social groups, few have analyzed the causes of contrasts in kinship among related species. Here, we describe interspecific differences in average kinship between group members among social mammals and show that a simple mathematical model that includes the number of breeding females, male reproductive skew, and litter size successfully predicts ~95% of observed variation in average kinship between group members across a sample of mammals. Our model shows that a wide range of conditions can generate groups with low average relatedness but only a small and rather specific set of conditions are likely to generate high average levels of relatedness between their members, providing insight into the relative rarity of advanced forms of cooperation in mammalian societies.

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