Anuran predators overcome visual illusion: dazzle coloration does not protect moving prey
Predators everywhere impose strong selection pressures on the morphology and behavior of their prey, but the resulting antipredator adaptations vary greatly among species. Studies of adaptive coloration in prey species have generally focused on cryptic or aposematic prey, with little consideration of color patterns in palatable mobile prey. Complex color patterns have been proposed to decrease the ability of visual predators to capture moving prey (motion dazzle effect). Most support for this hypothesis, however, comes from experiments with human subjects and simulated prey. We tested the motion dazzle effect using, for the first time, natural predators (cane toads, Rhinella marina) and live prey (house crickets, Acheta domesticus) with altered color patterns. We found no support for the motion dazzle effect as striped crickets did not fare better than solid colored ones. Crickets that spent more time moving, however, were more likely to be eaten. Our results suggest that motion specialized visual predators such as toads overcome the motion dazzle effect and impose stronger selection pressure on prey behavior than on coloration. These findings emphasize the importance of sensory specializations of predators in mediating antipredator strategies.
KeywordsMotion dazzle Camouflage Antipredator adaptation Bufo marinus
We are grateful to J. Lam, N. Anderson, and C. Pantoja, for running experimental trials, R. Lim and E. Shank for coding videos, and J. Peniston for designing figures. We also thank H. Legett, B. Leavell, and F. Boyd for collecting the cane toads used in this study, and D. Pita for measuring the reflectance spectra of the crickets. Members of the Bernal lab provided suggestions that helped improve this manuscript.
This study was funded by the Department of Biological Sciences at Purdue University. X.E.B. was funded by NSF IOS no. 1433990.
Compliance with ethical standards
Conflict of interest
All authors declare that they have no conflicts of interest.
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. Our experiments were approved by the Purdue Animal Care and Use Committee (Protocol #1405001073). This article does not contain any studies with human participants performed by any of the authors.
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