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Temporal and Contextual Consistency of Leadership in Homing Pigeon Flocks

Carlos D. Santos, Stefanie Neupert, Hans-Peter Lipp, Martin Wikelski, Dina K. N. Dechmann, Gonzalo G. de Polavieja
2014 PLoS ONE  
We compared two contexts of flock composition: flocks of birds of the same age and flight experience; and, flocks of birds of different ages and flight experience.  ...  However, flocks of balanced age and flight experience exhibited reduced leadership stability, indicating that these factors promote flock structuring.  ...  Acknowledgments We thank Irina Lipp for pigeon care and training, and Jessica Schnell, Scott LaPoint and Marco Smolla for comments on the manuscript.  ... 
doi:10.1371/journal.pone.0102771 pmid:25054203 pmcid:PMC4108361 fatcat:tt3iafqqnvfepcyia3hc243svi

The instability of followers and emergent vorticity in flocking behaviour for an experimental interaction rule [article]

Michael Small, Xiaoke Xu
2012 arXiv   pre-print
We find that the introduction of a small number of such followers causes a phase transition that quickly leads to instability in the flock structure (as no stable configuration arises) and the previously  ...  For a wide range of flock size and interaction extent (the fixed number of neighbors with which an individual will interact) we find that the computational collective is inherently stable --- individuals  ...  We find that the introduction of a small number of such followers causes a phase transition that quickly leads to instability in the flock structure (as no stable configuration arises) and the previously  ... 
arXiv:1207.5290v1 fatcat:orn52ztg5bhqhatzghlgjqwhaq

Assessing Population Structure and Genetic Diversity in U.S. Suffolk Sheep to Define a Framework for Genomic Selection

Carrie S Wilson, Jessica L Petersen, Harvey D Blackburn, Ronald M Lewis
2022 Journal of Heredity  
. using molecular data; and 4) assessing genetic relationships (connectedness) among active Suffolk flocks (n=18) in NSIP.  ...  By characterizing genetic diversity, a goal was to define the structure of a reference population for use for genomic selection strategies in this breed.  ...  flocks.  ... 
doi:10.1093/jhered/esac026 pmid:35575262 fatcat:wlgvxgcfcjgobdvwqzdfriim3m

Reciprocal relationships in collective flights of homing pigeons

Xiao-Ke Xu, Graciano Dieck Kattas, Michael Small
2012 Physical Review E  
Collective motion of bird flocks can be explained via the hypothesis of many wrongs, and/or, a structured leadership mechanism.  ...  We show that both reciprocal relationships and a stratified hierarchical leadership are important and necessary in the collective movements of pigeon flocks.  ...  Máté Nagy who kindly provided the trajectory data of pigeon flocks.  ... 
doi:10.1103/physreve.85.026120 pmid:22463292 fatcat:jwgpklc4pneqva26t4okhha6ie

Three-dimensional trajectories and network analyses of group behaviour within chimney swift flocks during approaches to the roost

Dennis J. Evangelista, Dylan D. Ray, Sathish K. Raja, Tyson L. Hedrick
2017 Proceedings of the Royal Society of London. Biological Sciences  
We found that the swift flock is structured around local rules based on physical distance, that subgroup size increases with density, and that there exist regions of the flock that are less cooperative  ...  We recorded the three-dimensional trajectories of %1 800 individual birds during a 30 min period encompassing flock formation, circling, and landing, and used these trajectories to test several hypotheses  ...  Omerspahic and A. Lohmann. We also thank M. Betke, D. Theriault, N. Fuller, K. Morgansen, J. Ballieul, Z. Wu, S. Kane, I. Yeaton, and Y. Munk for discussion of preliminary results and K.  ... 
doi:10.1098/rspb.2016.2602 pmid:28202812 pmcid:PMC5326531 fatcat:ppiuyy64ejettcdxfcyapus5e4

An orderly algorithm and some applications in finite geometry

Gordon F. Royle
1998 Discrete Mathematics  
We illustrate this with examples of searches in finite geometry, and an extended application where we classify all the maximal partial flocks of the hyperbolic and elliptic quadrics in PG(3, q) for q~<  ...  An algorithm for generating combinatorial structures is said to be an orderly algorithm if it produces precisely one representative of each isomorphism class.  ...  out that partial flocks of deficiency one were interesting and that the problem could be naturally expressed as a clique-searching problem.  ... 
doi:10.1016/s0012-365x(97)00167-2 fatcat:3emcizlrwffn3difyj5flabwt4

Genetic diversity analysis of Indonesian native chickens using SNP markers on the Z chromosome

Riztyan, Nyoman SUTHAMA, Sri Murni ARDININGSASI, Takeshi SHIMOGIRI, Kotaro KAWABE, Yasuhiro KAWAMOTO, Shin OKAMOTO
2011 The Journal of Animal Genetics  
Genetic diversity and matrix pairwise distance F ST were computed for 23 BK, 116 LOC, 20 AR, and 29 KD chickens. Average expected heterozygosity was greater in LOC and KD than BK and AR.  ...  The lowest pairwise F ST value was estimated at 0.028 (P<0.05) between LOC and KD. In contrast, the pairwise F ST value between BK and AR was larger (0.092) and was significant (P<0.05).  ...  In a study of the conservation of South African indigenous chickens, four flocks were separated using structure-based clustering analysis into four independent clusters, whereas a random sample of chicken  ... 
doi:10.5924/abgri.39.49 fatcat:qbvhopul3ngflnof52rkyhtln4

Intermittence and connectivity of interactions in pigeon flock flights

Duxin Chen, Xiaolu Liu, Bowen Xu, Hai-Tao Zhang
2017 Scientific Reports  
while retaining the agility and stability of the group.  ...  This biological observation strongly suggests the presence of a jointly connected topology in pigeon flocks, which helps substantially reduce the communication and/or information processing requirements  ...  The work of H.  ... 
doi:10.1038/s41598-017-09986-5 pmid:28874738 pmcid:PMC5585366 fatcat:fuv5hvyn2rajpkolw6tmjumskm

Clusterflock: A Flocking Algorithm for Isolating Congruent Phylogenomic Datasets [article]

Apurva Narechania, Richard H Baker, Rob DeSalle, Barun Mathema, Barry Kreiswirth, Sergios-Orestis Kolokotronis, Paul J Planet
2016 bioRxiv   pre-print
In addition to their unsupervised nature, flocking offers several computational advantages including the potential to decrease the number of required comparisons.  ...  Pairwise distances that measure the phylogenetic incongruence between OGFs guide flock formation.  ...  In addition to their unsupervised nature, flocking offers several computational advantages including the potential to decrease the number 10! of required comparisons.  ... 
doi:10.1101/045773 fatcat:jecqobcq7jgirocqivwau3ohqm

Clusterflock: a flocking algorithm for isolating congruent phylogenomic datasets

Apurva Narechania, Richard Baker, Rob DeSalle, Barun Mathema, Sergios-Orestis Kolokotronis, Barry Kreiswirth, Paul J. Planet
2016 GigaScience  
Indeed the flocking algorithm can cluster anything given precalculated pairwise distances between all entities.  ...  Here we test the flocking model against other clustering algorithms such as multidimensional scaling (MDS), hierarchical clustering, and partitioning around medoids .  ...  In addition to their unsupervised nature, flocking offers several computational advantages including the potential to decrease the number 10! of required comparisons.  ... 
doi:10.1186/s13742-016-0152-3 pmid:27776538 pmcid:PMC5078944 fatcat:bivl2sulorgn3cy26qd67njobu

Major inconsistencies of inferred population genetic structure estimated in a large set of domestic horse breeds using microsatellites

Stephan Michael Funk, Sonya Guedaoura, Rytis Juras, Absul Raziq, Faouzi Landolsi, Cristina Luís, Amparo Martínez Martínez, Abubakar Musa Mayaki, Fernando Mujica, Maria do Mar Oom, Lahoussine Ouragh, Yves-Marie Stranger (+2 others)
2020 Ecology and Evolution  
The over-reliance on K opt should be replaced by a qualitative description of clustering over increasing K, which is scientifically more honest and has the advantage of being much faster and less computer  ...  Different methods based on different genetic assumptions and statistical procedures (dapc, flock, PCoA, and structure with different run scenarios) all revealed general, broad-scale breed relationships  ...  The over-reliance on K opt should be replaced by a qualitative description of clustering over increasing K, which is scientifically more honest and has the advantage of being much faster and less computer  ... 
doi:10.1002/ece3.6195 pmid:32489595 pmcid:PMC7246218 fatcat:z72bmt5lpjd5zdc2k24trsyrfq

Recombinant Goose Circoviruses Circulating in Domesticated and Wild Geese in Poland

Tomasz Stenzel, Daria Dziewulska, Brejnev Muhire, Penelope Hartnady, Simona Kraberger, Darren Martin, Arvind Varsani
2018 Viruses  
Analysis of the secondary structure of the ssDNA genome revealed a conserved stem-loop structure with the G-C rich stem having a high degree of negative selection on these nucleotides.  ...  These genomes share 83-95% nucleotide pairwise identities with previously identified GoCV genomes, most are recombinants with exchanged fragment sizes up to 50% of the genome.  ...  The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.  ... 
doi:10.3390/v10030107 pmid:29498637 pmcid:PMC5869500 fatcat:eyedcmozozgabm7wuiek74z7ma

Outdoor flocking and formation flight with autonomous aerial robots [article]

Gábor Vásárhelyi and Csaba Virágh and Gergő Somorjai and Norbert Tarcai and Tamás Szörényi and Tamás Nepusz and Tamás Vicsek
2014 arXiv   pre-print
flocks.  ...  We do not use central data processing or control; instead, all the necessary computations are carried out by miniature on-board computers.  ...  The true advantage of a flocking flight over a single flying robot stands in its increased 'awareness', robustness and redundancy.  ... 
arXiv:1402.3588v2 fatcat:i3lr5xsbfndkvoj5vxtl7imfxm

Inferring the structure and dynamics of interactions in schooling fish

Y. Katz, K. Tunstrom, C. C. Ioannou, C. Huepe, I. D. Couzin
2011 Proceedings of the National Academy of Sciences of the United States of America  
However, pairwise interactions qualitatively capture the correct spatial interaction structure in small groups, and this structure persists in larger groups of 10 and 30 fish.  ...  Ballerini et al. (22) and Cavagna et al. (26) have used the spatial structure of starling flocks to infer that starlings use topological rather than metric interactions and that information is transferred  ...  We thank Irene Giardina, Guy Theraulaz, Naomi Leonard, Aryeh Warmflash, and members of the Couzin Laboratory  ... 
doi:10.1073/pnas.1107583108 pmid:21795604 pmcid:PMC3219116 fatcat:6d3w3dfzxjfqziu4tusnawuobm

Mining Massive-Scale Spatiotemporal Trajectories in Parallel: A Survey [chapter]

Pengtao Huang, Bo Yuan
2015 Lecture Notes in Computer Science  
However, to more effectively tackle the challenge of big data, it is important to exploit various advanced parallel computing paradigms.  ...  We also give an in-depth analysis of the related techniques and compare them according to their principles and performance.  ...  The advantage of GPU increased to around 10x speedup on the query processing task.  ... 
doi:10.1007/978-3-319-25660-3_4 fatcat:qdkslwlgjzesdfnzvkbrpsgmti
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