DOI: 10.5061/dryad.9cnp5hqqv
title: Data from: Sexually attractive traits predict predation-threat sensitivity of male alternative mating tactics

description: Although visual sexual signals, such as ornamental colors and courtship
 displays, and large body size in males are attractive to females in
 numerous species, they may also inadvertently attract the attention of
 eavesdropping predators and thus may be costly in terms of increasing
 individual risk of mortality to predation. Theoretically, more
 color-ornamented and larger males should be more predation threat
 sensitive and suppress their sexual signaling and(or) mating effort
 relatively more than their less color-ornamented and smaller counterparts
 when under predation hazard. Here, we experimentally tested this
 hypothesis by quantifying concurrently the rates of alternative mating
 tactics (courtship displays, sneak mating attempts) expressed by male
 Trinidadian guppies (Poecilia reticulata) varying in color ornamentation
 and body size under a staged immediate threat of predation. Males
 suppressed their overall mating effort in response to the perceived
 predation threat, decreasing the frequency of their (presumably more
 conspicuous) courtship displays significantly more on average than the
 frequency of their sneak mating behavior. Statistically controlling for
 body length, more color-ornamented males were more threat-sensitive in
 their courtship displays, but not sneak mating attempts, under predation
 hazard than drabber males. Controlling for body coloration, larger males
 exhibited lower courtship and sneak mating efforts than smaller males in
 both predation treatments, but body length only influenced threat
 sensitivity in sneak mating behavior. These results are consistent with
 both the threat-sensitive hypothesis and asset protection principle and
 highlight the phenotype-dependency and adaptive plasticity of alternative
 mating tactics in male guppies under varying predation risk.
description: In this experimental hypothesis-driven laboratory study,
 individual male Trinidadian guppies were exposed to a matched pair of
 predation-risk treatments (fish predator absent, fish predator present) in
 random order on the same day across the test subjects, and the frequencies
 of their courtship displays and sneak mating attempts directed towards two
 adult female guppies were recorded over 15 minutes.  A total of 53
 wild-caught males, varying naturally in body length and colour
 ornamentation, were similarly tested for the threat sensitivity of their
 two alternative mating tactics. The total body length (mm) and body colour
 ornamentation (proportion of body covered with pigmented and iridescent
 colours) of each test male were measured and quantified,
 respectively.  All data were analyzed in the R
 statistical framework and all statistical tests were two-tailed.  We used
 the R packages "tidyverse", "readxl",
 "ggbeeswarm" and "patchwork" for data wrangling and
 visualisation. Moreover, we used the R packages "glmmTMB" for
 analyses, "DHARMa" for diagnostic checks, and
 "emmeans" for extracting the coefficients of trend lines (along
 with their associated 95% confidence intervals and contrast) for each
 predator treatment. Depending on the biological hypothesis being tested,
 we used generalised linear mixed models (GLMM) or zero-inflated GLMMs to
 fit the observed frequencies of the two mating tactics, courtship displays
 and sneak mating attempts, as response variables. In each model, predator
 treatment, male body length and male body coloration, and their
 interactions, were included as fixed effect predictor variables, predator
 treatment order as a fixed covariable, and maleID as a random effect. For
 each of the final models, we separately plotted the raw data and predicted
 relationship (with its estimated slope and associated 95% CI) between the
 particular behavioural variable of interest (courtship display or sneak
 mating attempt rate) and either male color ornamentation or body length
 for each of the two predation treatments separately, while holding the
 other variables constant.  We tested the difference in slopes of the
 predicted relationships for the paired predator-absent and
 predator-present treatments, respectively, using the R package
 "emmeans".  We considered the difference in paired slopes being
 compared a measure of the predator threat sensitivity of the particular
 fitted behavioural variable.
description: # Data from: Sexually attractive traits predict predation-threat
 sensitivity of male alternative mating tactics
 [https://doi.org/10.5061/dryad.9cnp5hqqv](https://doi.org/10.5061/dryad.9cnp5hqqv) ## **Summary of experimental effort underlying the data set** In this experimental hypothesis-driven laboratory study, individual male Trinidadian guppies were exposed to a matched pair of predation-risk treatments (fish predator absent, fish predator present) in random order on the same day across the test subjects and the frequencies of their courtship displays and sneak mating attempts directed towards two adult female guppies recorded over 15 minutes.  A total of 53 wild-caught males, varying naturally in body length and colour ornamentation, were similarly tested for the threat sensitivity in their two alternative mating tactics. ## Description of the data and file structure The raw data are provided in an Excel file (.xlsx).  The data are organized in rows and columns in this file.  Each row contains the data for an individual male guppy, identified by a unique ID number.  The columns contain the variables: “Grouping” is coded 1 through 4, “Mating Tactic” is coded 1 (Courtship displays) or 2 (Sneak mating attempts),  “ExperimentalTreatment” is coded 1 (predator absent) or 2 (predator present), “TreatmentOrder” is coded 1 or 2.  The body length (mm) and colour ornamentation (proportion) of individual males are given in columns labelled “Length” and “PropTotalColour”, respectively.  Lastly, the column labelled “BehaviourRate” contains the behavioural response variable, that is, the rate (# acts/min) of the particular mating tactic (courtship display or sneak mating attempts) expressed by individual test males in either the present-absent or predator-present treatment. ## **Definition of all variables (columns) in the raw data file** | Variable Name | Description of variable | | ------------- | ----------------------- | | Grouping | Data groupings:   <br>1 = MatingTactic 1 (Courtship displays),  PredatorTreatment 1 (predator absent) <br>2 = MatingTactic 1 (Courtship displays),  PredatorTreatment 2 (predator present)<br>3 = MatingTactic 2 (Sneak mating attempts),  PredatorTreatment 1 (predator absent)    <br>4 = MatingTactic 2 (Sneak mating attempts),  PredatorTreatment 2 (predator present) | | MatingTactic | 1 = Courtship display rate (# acts/15 min) ; 2 = Sneak mating attempt rate (# acts/15 min) | | PredatorTreatment | 1 = Predator absent ; 2 = Predator present | | TreatmentOrder | 1 = Predator-present treatment presented first (in morning), with Predator-absent treatment presented second (in afternoon), on a given test day        <br>2 = Predator-present treatment presented second, with Predator-absent treatment presented first on a given test day | | MaleID | Identification number of individual test male guppy | | Length | Total length (mm) of individual test male guppy | | PropTotalColour | Proportion of total area of a test male guppy’s right side (including caudal fin) covered with all of the four classes of colour<br>(orange, black, fuzzy black and iridescent) | | BehaviourRate | Response variable. Observed frequency (# acts/15 min) of Courtship displays (MatingTactic code = 1) or Sneak mating attempts (MatingTactic code = 2) exhibited by an individual test male | ## Sharing/Access information N/A ## Code/Software R codes can be obtained upon reasonable request from the corresponding author.