Multimodal Aposematic Defenses Through the Predation Sequence

Show full item record



Winters , A E , Lommi , J , Kirvesoja , J , Nokelainen , O & Mappes , J 2021 , ' Multimodal Aposematic Defenses Through the Predation Sequence ' , Frontiers in Ecology and Evolution , vol. 9 , 657740 .

Title: Multimodal Aposematic Defenses Through the Predation Sequence
Author: Winters, Anne E.; Lommi, Jenna; Kirvesoja, Jimi; Nokelainen, Ossi; Mappes, Johanna
Contributor: University of Helsinki, Organismal and Evolutionary Biology Research Programme
Date: 2021-08-16
Language: eng
Number of pages: 18
Belongs to series: Frontiers in Ecology and Evolution
ISSN: 2296-701X
Abstract: Aposematic organisms warn predators of their unprofitability using a combination of defenses, including visual warning signals, startling sounds, noxious odors, or aversive tastes. Using multiple lines of defense can help prey avoid predators by stimulating multiple senses and/or by acting at different stages of predation. We tested the efficacy of three lines of defense (color, smell, taste) during the predation sequence of aposematic wood tiger moths (Arctia plantaginis) using blue tit (Cyanistes caeruleus) predators. Moths with two hindwing phenotypes (genotypes: WW/Wy = white, yy = yellow) were manipulated to have defense fluid with aversive smell (methoxypyrazines), body tissues with aversive taste (pyrrolizidine alkaloids) or both. In early predation stages, moth color and smell had additive effects on bird approach latency and dropping the prey, with the strongest effect for moths of the white morph with defense fluids. Pyrrolizidine alkaloid sequestration was detrimental in early attack stages, suggesting a trade-off between pyrrolizidine alkaloid sequestration and investment in other defenses. In addition, pyrrolizidine alkaloid taste alone did not deter bird predators. Birds could only effectively discriminate toxic moths from non-toxic moths when neck fluids containing methoxypyrazines were present, at which point they abandoned attack at the consumption stage. As a result, moths of the white morph with an aversive methoxypyrazine smell and moths in the treatment with both chemical defenses had the greatest chance of survival. We suggest that methoxypyrazines act as context setting signals for warning colors and as attention alerting or "go-slow" signals for distasteful toxins, thereby mediating the relationship between warning signal and toxicity. Furthermore, we found that moths that were heterozygous for hindwing coloration had more effective defense fluids compared to other genotypes in terms of delaying approach and reducing the latency to drop the moth, suggesting a genetic link between coloration and defense that could help to explain the color polymorphism. Conclusively, these results indicate that color, smell, and taste constitute a multimodal warning signal that impedes predator attack and improves prey survival. This work highlights the importance of understanding the separate roles of color, smell and taste through the predation sequence and also within-species variation in chemical defenses.
Subject: aposematism
Arctia plantaginis
Cyanistes caeruleus
defense mechanisms
multimodal signaling
predator-prey interactions
chemical defense
warning signals
1181 Ecology, evolutionary biology

Files in this item

Total number of downloads: Loading...

Files Size Format View
fevo_09_725467.pdf 976.5Kb PDF View/Open

This item appears in the following Collection(s)

Show full item record