To shimmer or not to shimmer: Collective defensive display in the Asian giant honeybee, Apis dorsata
Data files
Jul 02, 2026 version files 35.37 MB
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avani_etal_shimmering-main_supplementary.zip
35.37 MB
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README.md
5 KB
Abstract
Shimmering is a defensive behaviour exhibited by the open-nesting Asian giant honeybee Apis dorsata. During shimmering, bees on the outermost layer of the colony flip their abdomens in a coordinated manner, creating wave-like patterns that serve as an “I see you” signal to predators. Shimmering is triggered by a dark, moving object against a bright background, emphasising the role of contrast in initiating this behaviour. A. dorsata often constructs hives in visually heterogeneous habitats, such as tree canopies and thickets, or in human constructions, which can, in turn, interfere with the perception of approaching predators. Moreover, predators differ in the manner in which they approach A. dorsata colonies, from the saccadic flights of hornets to the swift approaches of bee-eaters. Our study experimentally investigates how background patterns and stimulus movement (looming vs lateral) influence shimmering behaviour. We used black-and-white chequered backgrounds of varying chequer sizes, while keeping the stimulus constant. Shimmering intensity reduced when the background pattern consisted of large chequer sizes, possibly because the stimulus was less discernible against this background. We then compared the shimmering response to a looming stimulus (akin to a bird predator’s flight) and a laterally moving stimulus (akin to a hornet’s flight). Bees responded to the laterally moving stimulus, but not to the looming stimulus. Furthermore, we examined how the movement of the stimulus within a restricted region in front of the hive affected the onset and intensity of shimmering. We found that shimmering was mostly initiated in the region proximal to the stimulus movement. By investigating the influence of both background heterogeneity and stimulus movement on shimmering, this study extends our understanding of this behaviour and demonstrates the effects of the visual habitat and predator motion on the shimmering response.
All files are contained within avani_etal_shimmering-main_supplementary.zip
Experiment_1.csv:
| Column | Descripion |
|---|---|
| Hive | Hive used in the trial |
| Background | Background used in the trial and corresponding grid size and visual angle (XS: 0.1 cm x 0.1 cm, 0.03 deg; S: 2.4 cm x 2.4 cm, 0.92 deg; S: 4.9 cm x 4.9 cm, 1.87 deg; L: 9.9 cm x 9.9 cm, 3.78 deg) |
| Experiment | Treatment/control |
| Area_Freq | Average of relative area of shimmer per trial |
| Area_median | Median of relative area of shimmer per trial |
| Area_max | Maximum value of relative area of shimmer per trial |
| Status | Inclusion status for analysis. Trials with confounding presence of hornets discarded from analysis |
Experiment_2.csv:
| Column | Descripion |
|---|---|
| Hive | Hive used in the trial |
| Stimulus | Size of the stimulus used in experiment |
| movementType | Stimulus movement executed by experimenter (lateral far, lateral near, looming, receding) |
| Experiment | Treatment/control |
| Area_Freq | Average of relative area of shimmer per trial |
Experiment_3.csv:
| Column | Descripion |
|---|---|
| Trial_num | Trial reference number |
| Movement | Range and zones of motion (Unrestricted, left zone or right zone) |
| Experiment | Treatment/control |
| Hive_region | Region of the hive where shimmering is measured from |
| Area_avg | Average of relative area of shimmer per trial (averaged across frames) |
| Area_sum | Cumulaitve relative area of shimmer per trial |
Shimmer Video.mp4:
Shimmering response in an A. dorsata colony from Experiment 2. Video of a trial looking at the shimmering response of Hive C in response to moving the stimulus (16 cm, 6.11° visual angle) in the lateral direction for one instance. The 'start' cue in the video denotes the onset of the experiment. The stimulus was moved from right to left, and the background was UV gray.
avani_etal_shimmering.Rproj:
R Project file
avani_etal_shimmering_2026.Rmd:
| Column | Descripion |
|---|---|
| Supplementary methods | Explaination of the content in the data sheets |
| Supplementary results | Code for beta-regression modelling and its outputs in plots and tabular form |
| Plots: figure 2-4 in main text | Code for plotting figure 2-4 in main text |
avani_etal_shimmering_2026.docx:
Output of the R Markdown file
avani_etal_shimmering_2026.pdf:
output of the R Markdown file
bw grid.ipynb:
Python code used to generate the black and white chequered background used for Experiment 1
zoneExp.ijm:
ImageJ/Fiji macro used to calculate the shimmering response in each zone of the hive for Experiment 3
