Data from: Glossiness disrupts predator localisation of moving prey
Data files
Feb 13, 2025 version files 858.88 KB
-
1_Specularity_spec.csv
711.62 KB
-
2_HemisphericalReflectance_spec.csv
77.56 KB
-
3_TrackingAnalysis_data.csv
55.93 KB
-
4_AttackAnalysis_data.csv
8.72 KB
-
README.md
5.06 KB
Abstract
Movement is the “enemy of camouflage”, but most animals must move to find resources, such as mates, food and shelter. Therefore, strategies that disrupt predator localization or speed perception of moving prey can play a crucial role in prey survival. Shiny or glossy appearances, which are characterised by having a high degree of specular (mirror-like) reflection of incident light, can disrupt predator hunting behaviours towards moving prey. Different mechanisms may explain this effect, but no study has attempted to identify the mechanisms that disrupt perception of moving glossy prey by non-human predators. Here, we present glossy green or grey targets to jumping spiders (Maratus griseus) and precisely document predator hunting behaviours using high speed videography. Jumping spiders were less precise at tracking glossy targets compared to control targets, suggesting glossiness may disrupt localisation of targets. Importantly for prey, jumping spider attack accuracy was substantially reduced towards glossy prey compared to control targets. These results were independent of underlying target colour, suggesting benefits of glossiness may be generalisable to differently coloured glossy animals. Our results indicate that glossiness creates an unpredictable target that is difficult for predators to localise, offering insights into the prevalence of dynamically coloured organisms in nature.
Data from: Glossiness disrupts predator localisation of moving prey
Amanda M. Franklin, Molly R. Brown, Nikolas J. Willmott
This files run the analyses in the above paper. All analysis files
are paired with data files (indicated by similar naming convention).
ANALYSIS FILES
1_Specularity.R: extracts parameters to calculate specularity and then plots result
2_HemisphericalReflectance.R: averages and plots hemispherical reflectance data
3_TrackingAnalysis.R: analysis of tracking data
4_AttackAnalysis.R: analysis of attack data
DATASETS
1_Specularity_spec.csv
Angular reflectance measurements at a series of predefined angles to quantify specularity
Links with: 1_Specularity.R
wl: wavelength (nanometers)
Columns 2:148 - spectra data for each target treatment and the arena (ARN). Three replicate measurements
for each angular measurement.
TREATMENTS:
GLS_GREN - glossy green
GLS_GREY - glossy grey
MAT_GREN - matte green
MAT_GREY - matte grey
BMT_GREN - background matching green
BMT_GREY - background matching grey
ANGULAR MEASUREMENT:
-525: light source at -5 degrees, collector at 25
0020: light source at 0 degrees, collector at 20
0515: light source at 5 degrees, collector at 15
1010: light source at 10 degrees, collector at 10
1505: light source at 15 degrees, collector at 5
2000: light source at 20 degrees, collector at 0
25-5: light source at 25 degrees, collector at -5
2_HemisphericalReflectance_spec.csv
Hemispherical reflectance data for each treatment at the arena measured with an integrating sphere.
Links with: 2_HemisphericalReflectance.R
wl: wavelength (nanometers)
Columns 2:21 - spectra data for each target treatment and the arena (ARN). Three replicate measurements
GLS_GREN - glossy green
GLS_GREY - glossy grey
MAT_GREN - matte green
MAT_GREY - matte grey
BMT_GREN - background matching green
BMT_GREY - background matching grey
3_TrackingAnalysis_data.csv
Dataset describing spider position and target position immediately before a jump. x,y coordinates
were recorded for the cephalothorax, abdomen and target for every frame in the video footage. These
were used to calculate spider body orientation angle and target angular position relative to spider
position. Links with 3_TrackingAnalysis.R
spiderID: identification number of the spider
Gloss: Treatment variable explaining target glossiness: glossy, matte or background matching
Colour: Treatment variable explaining target colour: grey or green
Treatment: Variable combining both colour and gloss
uqID: unique value for each spider for each treatment
time: time within video, based on frame rate (i.e. increment of 1 is 1/1000th of a second because videos were filmed at 1000fps)
head_xaxis: x-value for the cephalothorax
head_yaxis: y-value for the cephalothorax
body_xaxis: x-value for the abdomen
body_yaxis: y-value for the abdomen
target_xaxis: x-value for the target
target_yaxis: y-value for the target
slope_headbody: slope of a line intersecting the cephalothorax and abdomen points
intercept_headbody: y-intercept of a line intersecting the cephalothorax and abdomen points
slope_bodytarget: slope of a line intersecting the target and abdomen points
intercept_bodytarget: y-intercept of a line intersecting the target and abdomen points
angle_headbody: angle of the line intersecting the cephalothorax and abdomen points, from a horizontal line (degrees)
angle_bodytarget: angle of the line intersecting the target and abdomen points, from a horizontal line (degrees)
orientationangle_modelest: spider body orientation angle, estimated from the segmentation model (i.e. similar to angle_headbody)
angularoffset: difference between spider orientation and position of the target in degrees.
pointtype: if the angular measurement is at the start or end of a full body saccade
4_AttackAnalysis_data.csv
Behaviour data of spider attack behaviours during each trial. Data was recorded from
high speed video footage. Links with 4_AttackAnalysis.R
uqID: unique value for each spider for each treatmen
spiderID: identification number of the spider
Sex: sex of the spider (male or female)
Trial: trial number for an individual spider
Treatment: Variable combining both colour and gloss
Colour: Treatment variable explaining target colour: grey or green
Gloss: Treatment variable explaining target glossiness: glossy, matte or background matching
LatencyJump: latency until the spider jumped at the target after entering arena (seconds)
Jump.Dist: distance of jump from where spider began jump to target position (millimeters)
Jump.Acc: distance between target location and spider location at end of jump (millimeters)
Angle: angle between spider starting position, target and spider end position (degrees)
Flex.Legs: whether the spider flexed its legs, indicated attempt to catch target (yes/no)
CatchTarget: if the spider caught the target (yes/no)
VerDist: vertical offset between spider position and target (millimeter)
HoriDist: horizontal offset between spider position and target (millimeter)
NA: Not applicable