DOI: 10.5061/dryad.n02v6wwzz
title: Anisotropic interaction and motion states of locusts in a hopper band

description: Swarming locusts present a quintessential example of animal collective
 motion. Juvenile locusts march and hop across the ground in coordinated
 groups called hopper bands. Composed of up to millions of insects, hopper
 bands exhibit coordinated motion and various collective structures. These
 groups are well-documented in the field, but the individual insects
 themselves are typically studied in much smaller groups in laboratory
 experiments. We present the first trajectory data that detail the movement
 of individual locusts within a hopper band in a natural setting. Using
 automated video tracking, we derive our data from footage of four distinct
 hopper bands of the Australian plague locust, Chortoicetes terminifera. We
 reconstruct nearly twenty-thousand individual trajectories composed of
 over 3.3 million locust positions. We classify these data into three
 motion states: stationary, walking, and hopping. Distributions of relative
 neighbor positions reveal anisotropies that depend on motion state.
 Stationary locusts have high-density areas distributed around them
 apparently at random. Walking locusts have a low-density area in front of
 them. Hopping locusts have low-density areas in front and behind them. Our
 results suggest novel interactions, namely that locusts change their
 motion to avoid colliding with neighbors in front of them.
description: See Methods in the associated manuscript: https://doi.org/10.1101/2021.10.29.466390 See also the README file in the associated GitHub repository: https://github.com/weinburd/locust_trajectory_data
description: # Trajectory data for locusts in a hopper band
 [https://doi.org/10.5061/dryad.n02v6wwzz](https://doi.org/10.5061/dryad.n02v6wwzz) This repository contains data used in creating the work: * J Weinburd, J Landsberg, A Kravtsova, S Lam, T Sharma, SJ Simpson, GA Sword, C Buhl. *Anisotropic interaction and motion state of locusts in a hopper band.* Proc. R. Soc. B. **291: **20232121. [https://doi.org/10.1098/rspb.2023.2121](https://doi.org/10.1098/rspb.2023.2121) The contents include numerical position-time data extracted from raw video footage of locust hoppers in the field. The video was recorded by Drs. Stephen J Simpson, Greg A Sword, and Camille Buhl and provided as part of an ongoing collaboration. Students who have contributed to this project include: Anna Kravtsova (Eastern Washington U), Shanni Lam (HMC), Jacob Landsberg (Haverford), and Tarush Sharma (HMC). Give a brief summary of dataset contents, contextualized in experimental procedures and results. ## Description of the data and file structure The main data set is contained in two Matlab data files .mat which include cleaned and processed numerical trajectories and two subdirectories. 1. data_recording.mat, data_recording2.mat * contains the the full data set used in the manuscript linked above. **examples** contains all data files for the two example clips analyzed in pipeline_examples.m (see the link below to code hosted on GitHub). Includes the starting preprocessed video, intermediate processed video and .xml data files, and final data data_recording_examples.mat. **manual** contains the two ground-truth data sets obtained by manual tracking in TrackMate. Students **Jacob Landsberg** and **Tarush Sharma** did the bulk of the manual tracking. The original video files are also included so that the .xmls can be opened in Fiji&gt;Plugins&gt;Tracking&gt;Load a TrackMate File. The data variables themselves use Matlab's struct data format and can be somewhat opaque. Using a script in the code linked below (struct2data.m) one can convert the data variables into more intuitive 3D arrays where each row is a locust, each column is a feature, and the third dimension corresponds to time. ## Code/Software The code used to extract, clean, and process the trajectory data, to conduct the analysis, and to generate the figures and tables of the manuscript is available on the public GitHub repository: * [https://github.com/weinburd/locust_trajectory_data](https://github.com/weinburd/locust_trajectory_data)