Don’t waste your time: predators avoid prey with conspicuous colors that signal long handling time
Most studies on warning signal theory have focused on aposematic prey, which signal unpalatability through conspicuous signals. Palatable prey that are difficult to capture or process may also use conspicuous signals to advertise unprofitability to predators. Theory predicts that predators should avoid prey with long handling time, especially when other prey with shorter handling times are abundant. However, it is unclear if prey can benefit by signaling longer handling time. In experiments with dough models as prey, we show that chickens can learn to associate colors with increased handling time and avoid such prey when alternative prey are abundant. Overall, our experiment demonstrates that advertising longer handling time to predators can be advantageous to prey when other more profitable prey are abundant.
KeywordsHandling time Antipredatory strategies Conspicuous colorations
We thank Jayasooryan CS, Nawaf AM, Rohit Anand and Harshad Mayekar for help with the experiment. We thank Shaji for permitting us to carry out the experiment in his property. We thank Almut Kelber, Balamurali GS and Hema Somanathan for discussions. John Endler provided insightful comments on the manuscript. This study was funded by an INSPIRE Faculty Award from the Department of Science and Technology (DST/INSPIRE/04/2013/000476) to UK.
VPC conceived the study, designed and carried out the experiment, and analyzed the data; UK provided materials; VPC and UK wrote the paper and gave final approval.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. The experimental protocol was approved by the Institutional Animal Ethics Committee of Indian Institute of Science Education and Research Thiruvananthapuram.
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