TY - JOUR TI - Signal categorization by foraging animals depends on ecological diversity AU - Kikuchi, David William AU - Dornhaus, Anna AU - Gopeechund, Vandana AU - Sherratt, Thomas N A2 - Schmid, Bernhard A2 - Baldwin, Ian T A2 - Schmid, Bernhard VL - 8 PY - 2019 DA - 2019/04/25 SP - e43965 C1 - eLife 2019;8:e43965 DO - 10.7554/eLife.43965 UR - https://doi.org/10.7554/eLife.43965 AB - Warning signals displayed by defended prey are mimicked by both mutualistic (Müllerian) and parasitic (Batesian) species. Yet mimicry is often imperfect: why does selection not improve mimicry? Predators create selection on warning signals, so predator psychology is crucial to understanding mimicry. We conducted experiments where humans acted as predators in a virtual ecosystem to ask how prey diversity affects the way that predators categorize prey phenotypes as profitable or unprofitable. The phenotypic diversity of prey communities strongly affected predator categorization. Higher diversity increased the likelihood that predators would use a ‘key’ trait to form broad categories, even if it meant committing errors. Broad categorization favors the evolution of mimicry. Both species richness and evenness contributed significantly to this effect. This lets us view the behavioral and evolutionary processes leading to mimicry in light of classical community ecology. Broad categorization by receivers is also likely to affect other forms of signaling. KW - community ecology KW - animal communication KW - receiver psychology JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -