DOI: 10.5061/dryad.2jm63xstq
title: Plains zebra 2019 multimodal communication dataset

description: Multimodality is a virtually ubiquitous feature of communication. With the
 increasing interest in how animals, including humans, use multimodal and
 multicomponent signals in social interactions, there is an acute need for
 standardized and rigorous tools that will allow us to visualize, and
 analyze these signals as they occur in naturalistic interactions as a
 complex, integrated system. Network theory is a powerful methodology for
 intuitively visualizing and investigating the relationships between
 entities. Here, we propose a new application of network theory for
 analyzing multimodal communication. Using a case study of natural
 multimodal interactions in wild plains zebras (Equus quagga), we introduce
 the descriptive power of network metrics by providing an objective set of
 metrics to: (a) describe the relationships between simultaneously produced
 signals within and between modalities; and (b) infer signal meaning and
 function. Here we make available the multimodal communication data
 collected during our 2019 field season.
description: <strong>Ethical Note</strong>. This was a purely
 observational study conducted on free-living wild animals in Ol Pejeta
 Nature Conservancy (0°00 N, 36°56 E). Though the zebras in this population
 are habituated to the presence of humans in vehicles due to year-round
 tourist activity, we made efforts to minimize disturbance of natural
 behaviors during follows by ensuring the research vehicle never separated
 or obscured direct visual contact between harem-members, and by never
 redirecting natural harem movements (i.e., driving in front of the line of
 travel to induce a direction change). All research was conducted with the
 permission of Ol Pejeta Nature Conservancy and the Kenyan Ministry of
 Wildlife, and was in compliance with the guidelines of the Princeton
 University Institutional Animal Care and Use Committee (IACUC protocol
 #1835F). <strong>Study Species and
 Subjects</strong>. We collected our data on free-living wild animals
 in Ol Pejeta Nature Conservancy (0°00 N, 36°56 E). We have been monitoring
 this population since 2001, using periodic census loops at an interval of
 1 week (range: 1 day – 1 month) to collect data on associations, movement,
 and demography of individuals in the population. We are able to
 individually identify zebras based on their unique stripes. Data analysis
 was conducted on a focal subset of the population; 5 harems and one
 bachelor group. The harems consisted of 22 individuals, and group size
 ranged from 3 to 7 individuals (2 to 5 adult members). The focal bachelor
 group, KRT, comprised five individuals who were consistently in
 association across the study period.
 <strong>Observations and Data
 Collection</strong>. Data collection occurred for 15 days between
 July 9th thru August 9th 2019 on the Eastern Sector of Ol Pejeta
 Conservancy. Observations occurred between 09:00-15:00, during which time
 a single focal group would be the subject of a focal follow for 2-4
 consecutive hours. Interactions were captured with video using a Canon
 Vixia HR R700, and audio was recorded using a Sennheiser ME66 directional
 microphone in a Rode Blimp windshield and a Tascam Dr-100MKII Linear PCM
 recorder sampling at 48kHz. We adopted an all-occurrences sampling
 procedure in which we ad libitum captured interactions of individuals of
 the focal harem. We amassed 45 contact hours during
 this study period. Of the collected footage, we only coded interactions in
 which the entire body of the focal individual was visible and unobscured,
 and eliminated videos in which the individuals were not in focus,
 partially out of frame, obscured by foliage or non-focal animals, or too
 distant for reliable coding of all regions of interest. This filtering
 yielded 13 hours of usable footage in which at least one interaction takes
 place involving a focal animal. We cleaned our sample data prior to
 analysis by removing all postures where one of the minimally necessary
 occurring visual units (i.e. ears, eyes, lower face, neck, tail) was not
 able to be coded. We also removed rare multimodal postures by eliminating
 those containing a component that was observed in &lt; 2 interactions
 to improve the interpretability of our results by only considering
 components for which we had adequate co-occurrence data. After these
 cleaning steps, we were left with 1,594 high-quality multimodal
 postures. <strong>Coding
 Scheme</strong>. For every interaction, we designated one individual
 as the focal individual and coded every signal produced by that animal for
 the duration of the interaction. If possible, dyadic interactions were
 coded twice, one with each interactant as the focal animal to capture both
 sides of an interaction, especially if the interaction was asymmetric
 (e.g., a dominance interaction). An interaction was defined as beginning
 when two individuals entered one body length of one another and the sender
 was 1) oriented towards the receiver, 2) the signal was produced in the
 direction of the receiver, 3) the sender approached the receiver, and/or
 4) the sender made physical contact with the receiver. An interaction was
 defined as terminated when either 1) one individual moved beyond one body
 length of the other without being followed, or 2) the parties ceased
 interacting for at least 10 seconds (e.g., began to graze or sleep in
 proximity).