Honest signalling in predator-prey interactions: testing the resource allocation hypothesis
Data files
Jul 11, 2025 version files 448.55 KB
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bird_response_female.txt
19.48 KB
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BirdVisionHonestyAlldata.txt
402.09 KB
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LifeHistory_Honesty.txt
23.68 KB
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README.md
3.31 KB
Abstract
Warning signals are honest if they reliably deliver information about prey unprofitability to predators. One potential mechanism that may create and maintain a positive relationship between the strength of signals and defence is the resource allocation between these costly traits. Here, we test this hypothesis using the wood tiger moth Arctia plantaginis, whose females’ red hindwings are a warning signal to predators but show considerable variation in colouration within populations. These moths also produce a defensive chemical that is known to influence avian predator attack risk. Using dietary manipulations, image and chemical analyses, and experiments with ecologically relevant predators we demonstrate that protein availability during development can influence the strength of both the primary warning signal and the secondary defence. Our results show that females raised on a high-protein or ad libitum natural diet produced more distasteful defensive fluids than those raised on a low-protein diet or subjected to periodic food deprivation. While the patterning of the warning signal was unaffected by food deprivation, its efficacy was diminished in moths raised on a low-protein diet. However, this change was imperceptible to avian predators. Critically, resource availability influenced the relationship between signal strength and defence: moths on a high-protein diet displayed a positive correlation between warning signal strength and unpalatability, whereas this correlation was absent in moths raised on a natural diet. These findings show that resource availability can weaken the reliability of warning signals as an indicator of an individual’s defensive capabilities, highlighting the complex interplay between ecological conditions and the evolution of honest signalling.
This dataset includes the txt files:
- BirdVisionHonestyAlldata.txt — Data on image analysis of wood tiger moth wings
- bird_response_female.txt — Data of predator responses to female moths' thoracic fluids under different diet treatments
- LifeHistory_Honesty.txt — Life-history data for moth individuals under different treatments.
1. BirdVisionHonestyAlldata.txt
This file contains measurements from vision modelling and reflectance spectra for individual moths. Each row corresponds to a specific ROI (region of interest) from a moth wing.
Key columns include:
- Label: Unique label for each moth and ROI
- ID: ID of individual moth
- Treatment: Diet treatment of the moth (DH: natural diet ad libitum; DL: natural diet food deprived one day per week; NH: high protein diet; NL: low protein diet)
- Family: Moth family
- ROIs: Region of interest on the wing (e.g., f1, h1)
lumMean
,lumSD
: Mean and standard deviation of luminance- area: Area of the ROI in pixels
maxPower
,maxFreq
: Peak power and frequency of reflectancemwMean
,mwSD
: Mean and SD for medium-wavelength cone stimulationlwMean
,lwSD
: Mean and SD for long-wavelength cone stimulationdblMean
,dblSD
: Mean and SD of double cone stimulationU
,B
,G
,R
: Cone responses for UV, Blue, Green, and Red conesLum
: Final luminance value
2. bird_response_female.txt
This file includes predator response data (e.g., hesitation, approach time) from trials in which birds interacted with thoracic fluids of moths.
Key columns include:
birdid
: ID of the birdsex
: Sex of the birdage
: Age category of the bird (juvenile/adult)treatment
: Diet treatment of the moth (DH: natural diet ad libitum; DL: natural diet food deprived one day per week; NH: high protein diet; NL: low protein diet)colour
: Colour morph of the mothtrial
: Trial number (1 to 4)tsee
: Time (s) when bird saw the baittapp
: Time (s) when bird approached the baittattack
: Time (s) when bird attacked the baitteat
: Time (s) when bird started eating the baitlatattack
: Latency to attacklateat
: Latency to eatpropeat
: Proportion of bait eatenpbw
: Beak wipe occurred (1/0)nbw
: Number of beak wipespw
: Drinking occurred (1/0)nw
: Number of drinkspsh
: stress-related behavior (0/1)tfinal
: Trial end time (s)tduration
: Trial duration (s)
Missing values are marked as 'na'
3. LifeHistory_Honesty.txt
This file includes life-history trait data from individual moths exposed to different diet treatments.
Key columns include:
ID
: Unique ID of the mothFamily
: Family identifier of the mothIndividual_number
: Individual label within familytreatment
: Diet treatment (e.g., DH, DL, NH, NL)pupa_weigh
: Weight of the pupae (mg)survival
: Binary indicator of survival (1 = survived, 0 = did not)development_time
: Days taken to developgrowth_rate
: Relative growth ratesex
: Sex of the individual (typically "female")ok
: Developmental quality or condition (e.g., ok, bad, pupa, crumpled)N_volume
: Volume (µl) of thoracic fluid (chemical defence)