Pigeons use tree structures as the leadership structure for flocking
Data files
Apr 10, 2024 version files 686.70 KB
Abstract
Collective behaviors leading to various fascinating movement patterns are believed to be the product of complex interplay among individuals. Previous studies have identified two types of leadership structures in pigeon flocks, i.e., hierarchical networks and reciprocal relationships. However, both of these leadership structures are predicated based on data analysis and lack substantial empirical evidence. Additionally, it is difficult to delineate a direct correspondence between leadership structures and trajectory data for pigeon flocks because birds cannot report their leadership structure. Herein, we demonstrated that pigeons adopt leadership relationships that can be characterized as tree structures. In a tree structure, each follower follows its only leader during collective flights, and the single top leader determines the entire flock's flight direction. In the present study, we performed experiments using student volunteers who could report leadership relationships. We identified a one-to-one correspondence between leadership structures and data characteristics and proposed a method for determining the leadership structure based on trajectory data. This strategy was used to analyze flight trajectory data from a pigeon flock and elucidate the pigeons' leadership relationships. The developed approach could effectively model the collective behavior of pigeon flocks, thus accurately replicating findings from previous experimental studies. The results of this study provide insights regarding the leadership structure in pigeon flocks and have implications for artificial collective systems, e.g., autonomous formation control of multiple unmanned aerial vehicles or unmanned surface vehicles.
README: Pigeons use tree structures as the leadership structure for flocking
https://doi.org/10.5061/dryad.15dv41p4h
PigeonFight_Data
The file named DATA_G^i_j (i,j=1,2,3) represents the trajectory data of all individuals in the experiment C^i_j. Each data file DATA_G^i_j contains 16 columns of data. These 16 columns of data are divided into 8 pairs in chronological order, which are the coordinates of A, B, C, D, E, F, G, and H, respectively. Specifically, the two columns in each pair of data record the horizontal and vertical coordinates of an individual's movement process, respectively. The time interval between adjacent data is 1/20s.
The files named tau*-G^i_j and C*-G^i_j respectively record \tau* and C* in the experiment C^i_j. The order of the data is consistent with the data order in Table 1 of the main text.
Methods
Participants and experimental protocols: Twenty-four graduate students participated in the experiments. They were randomly divided equally into three groups of eight, i.e., G1, G2, and G3, and three repeated experiments (Gi, Gi, Gi, i = 1, 2, 3) were performed for each group. For example, G1 represents the second experiment with the group G1. Each group of students jogs under the leadership relationship we have set up. The leadership relationship requires each individual, except for the main leader, to choose only one leader to follow, and individuals cannot be leaders of one another. The main leader does not have a leader and serves to lead the movement of the flock. The leadership relationship adopts a tree structure, where each individual can only follow its immediate leader.
Device and data handling: The movements of the crowds/flocks were recorded using an unmanned aerial vehicle (DJI MAVIC 3 PRO) in the air at 60 Hz. On the video recordings, individuals were tracked with a cursor using the free TRACKER software. This established tracks (xi, yi; ti), where (xi, yi) represents the position vector of the individuals at time ti with the time interval of ∆t = 1/20 s.