A1 Journal article (refereed)
Safety in Numbers : How Color Morph Frequency Affects Predation Risk in an Aposematic Moth (2021)

Gordon, S. P., Burdfield-Steel, E., Kirvesoja, J., & Mappes, J. (2021). Safety in Numbers : How Color Morph Frequency Affects Predation Risk in an Aposematic Moth. American Naturalist, 198(1), 128-141. https://doi.org/10.1086/714528

JYU authors or editors

Publication details

All authors or editors: Gordon, Swanne P.; Burdfield-Steel, Emily; Kirvesoja, Jimi; Mappes, Johanna

Journal or series: American Naturalist

ISSN: 0003-0147

eISSN: 1537-5323

Publication year: 2021

Publication date: 01/07/2021

Volume: 198

Issue number: 1

Pages range: 128-141

Publisher: University of Chicago Press

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1086/714528

Research data link: https://doi.org/10.5061/dryad.c866t1g69

Publication open access: Not open

Publication channel open access:

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/78471

Additional information: This article originated as part of the 2020 Vice Presidential Symposium. The symposium was originally scheduled for the 2020 annual meeting of the American Society of Naturalists in Cleveland, Ohio; because of the COVID-19 pandemic, it instead occurred at the Virtual Asilomar meeting in January 2021.


Polymorphic warning signals in aposematic systems are enigmatic because predator learning should favor the most common form, creating positive frequency-dependent survival. However, many populations exhibit variation in warning signals. There are various selective mechanisms that can counter positive frequency-dependent selection and lead to temporal or spatial warning signal diversification. Examining these mechanisms and their effects requires first confirming whether the most common morphs are favored at both local and regional scales. Empirical examples of this are uncommon and often include potentially confounding factors, such as a lack of knowledge of predator identity and behavior. We tested how bird behavior influences the survival of three coexisting morphs of the aposematic wood tiger moth Arctia plantaginis offered to a sympatric predator (great tit Parus major) at different frequencies. We found that although positive frequency-dependent selection is present, its strength is affected by predator characteristics and varying prey profitability. These results highlight the need to understand predator foraging in natural communities with variable prey defenses in order to better examine how behavioral interactions shape evolutionary outcomes.

Keywords: natural selection; warning coloration; variation (biology); predation; wood tiger

Free keywords: frequency-dependent selection; aposematism; warning coloration; context-dependent predation; polymorphism

Contributing organizations

Related projects

Ministry reporting: Yes

Reporting Year: 2021

JUFO rating: 3

Last updated on 2023-03-10 at 11:58