Directional Selection on Color in the Dyeing Poison Frog (<em>Dendrobates tinctorius</em>) — ASN Events

Directional Selection on Color in the Dyeing Poison Frog (Dendrobates tinctorius) (#103)

Justin P Lawrence 1 , Antoine Fouquet 2 , Bibiana Rojas 3 , Renan J Bosque 1 , Elodie A Courtois 2 , Johanna Mappes 3 , Brice P Noonan 1
  1. University of Mississippi, Oxford, MISSISSIPPI, United States
  2. CNRS-Guyane, Cayenne, French Guiana
  3. Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland

Aposematic (warning) coloration is a defensive strategy found throughout the animal kingdom. The phenomenon relies on frequency dependence of an aposematic signal for local predators to learn and associate the signal with unpalatability. Theory predicts that more common signals (morphs) should be favored against novel forms. While there is great variation in aposematic signal found throughout the animal kingdom, some components to signal (i.e., yellow coloration) are ubiquitous across many taxa. This ubiquity suggests that some components to signal are more effective for predator learning than others. By using both field and lab experiments, we studied how signal polytypism may evolve in the Dyeing Poison Frog (Dendrobates tinctorius). This species is found throughout the Guiana Shield and exhibits a wide variety of color and pattern combinations. We examined predator response to novel colors and patterns by placing plasticine clay models in two different sites in French Guiana where color but not pattern differ. Models placed in each area had either the local color and pattern, local color and novel pattern, or local pattern and novel color. At one site, avian predators attacked the local morph more often than expected by chance, but had equal avoidance of all models in our second site. In controlled lab experiments, we trained chickens (Gallus domesticus) on either yellow or white stripes at two different chloroquine concentrations and recorded how likely predators learned signal. While concentration of chloroquine did not have any effect, chickens did learn to avoid and hesitate longer the yellow signal. These results suggest that yellow is a more optimal color for avian predator learning and that there is directional selection to yellow in wild populations of D. tinctorius. These results explain why some components to aposematic signal are so ubiquitous through aposematic taxa.