DOI: 10.5061/dryad.xksn02vnf
title: Predator selection on multicomponent warning signals in an aposematic moth

description: Aposematic prey advertise their unprofitability with conspicuous warning
 signals that are often composed of multiple color patterns. Many species
 show intraspecific variation in these patterns even though selection is
 expected to favor invariable warning signals that enhance predator
 learning. However, if predators acquire avoidance to specific signal
 components, this might relax selection on other aposematic traits and
 explain variability. Here we investigated this idea in the aposematic moth
 Amata nigriceps that has conspicuous black and orange coloration. The size
 of the orange spots in the wings is highly variable between individuals,
 whereas the number and width of orange abdominal stripes remain
 consistent. We produced artificial moths that varied in the proportion of
 orange in the wings or the presence of abdominal stripes. We presented
 these to a natural avian predator, the noisy miner (Manorina
 melanocephala), and recorded how different warning signal components
 influenced their attack decisions. When moth models had orange stripes on
 the abdomen, birds did not discriminate between different wing signals.
 However, when the stripes on the abdomen were removed, birds chose the
 model with smaller wing spots. In addition, we found that birds were more
 likely to attack moths with a smaller number of abdominal stripes.
 Together, our results suggest that bird predators primarily pay attention
 to the abdominal stripes of A. nigriceps, and this could relax selection
 on wing coloration. Our study highlights the importance of considering
 individual warning signal components if we are to understand how predation
 shapes selection on prey warning coloration.
description: We conducted field experiments with wild noisy miners in NSW,
 Australia, between September 2020 and March 2022. We conducted three
 different experiments where birds were presented with a choice between two
 artificial moth models to test their preference for 1) small vs. large
 orange wing spots when the abdomen was black, 2) small vs. large orange
 wing spots when the abdomen had stripes, and 3) low vs. high number of
 abdominal stripes. Bird' choices (which moth model was attacked
 first) were filmed with small video cameras.
description: # Predator selection on multicomponent warning signals in an aposematic
 moth
 [https://doi.org/10.5061/dryad.xksn02vnf](https://doi.org/10.5061/dryad.xksn02vnf) There are three different data files that include the data from three experiments: Experiment 1: The effect of wing spots without abdominal stripes Experiment 2: The effect of wing spots and abdominal stripes Experiment 3: The effect of abdominal stripes In each experiment, the birds were presented with two artificial moth models with different warning signals and we recorded their first choice. In each file, the datasheet contains the bird number, test location name and coordinates, and the date and the starting time of the experiment. There were four feeders in each location and the column "Feeder\_number" describes which of the feeders the bird visited. The column "Signal\_choice" describes the signal type that the bird attacked: small/large wing spots in Experiment 1 and 2, and three/five abdominal stripes in Experiment 3. The column "Side\_choice" describes whether birds attacked the moth on the left or right side of the tray. The column "Order" describes whether the bird attacked that signal type as their first choice (value 0), or as a second choice or not at all (value 1). The column "Attacked\_both\_moths" describes whether birds attacked both moth models during the same visit ("yes"), or whether they flew away after attacking the first model ("no"). Because Experiment 1 was conducted in two different study sites, the datasheet of that experiment includes the column "Site" (Macquarie University campus/ Newholme Research Station). Some of the birds at the Newholme Research station were colour banded, and the datafile also includes columns "Left\_colour\_tag" and "Right\_colour\_tag" that describe the individual colour bands of the birds. The R script for the analyses is included with the data files.