Predator selection on phenotypic variability of cryptic and aposematic moths

• Published in: Nature communications Vol. 15; no. 1; p. 1678
• Main Authors: Nokelainen, Ossi, Silvasti, Sanni A., Strauss, Sharon Y., Wahlberg, Niklas, Mappes, Johanna
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 23-02-2024; Nature Publishing Group; Nature Portfolio
• Subjects: 631/158/856; 631/158/857; 631/181/2481; Animals; Aposematism; Biologi; Biological Sciences; Biological Variation, Population; Butterflies & moths; Camouflage; Color; Cryptic species; Evolutionary Biology; Evolutionsbiologi; Genetic variability; Humanities and Social Sciences; Image analysis; Image processing; Moths; multidisciplinary; Natural Sciences; Natural selection; Naturvetenskap; Northern Hemisphere; Patterning; Phylogeny; Predators; Predatory Behavior; Science; Science (multidisciplinary); Selection, Genetic; Species; Variability; Wings
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-45329-5

Natural selection generally favours phenotypic variability in camouflaged organisms, whereas aposematic organisms are expected to evolve a more uniform warning coloration. However, no comprehensive analysis of the phenotypic consequences of predator selection in aposematic and cryptic species exists. Using state-of-the-art image analysis, we examine 2800 wing images of 82 moth species accessed via three online museum databases. We test whether anti-predator strategy (i.e., camouflage or aposematism) explains intraspecific variation in wing colour and pattern across northern hemisphere moths. In addition, we test two mutually non-exclusive, ecological hypotheses to explain variation in colour pattern: diel-activity or dietary-niche. In this work, taking into account phylogenetic relationships, moth phenotypic variability is best explained by anti-predator strategy with camouflaged moths being more variable in wing patterning than aposematic species.
Selection is expected to act differently on aposematic and cryptic species. Analysis of wing images revealed that camouflaged moths exhibit higher wing pattern variability than aposematic moths, supporting the theory that camouflaged species display more variability, consistent with anti-predator strategy.