title: Disruptive camouflage impairs object recognition.
abstract: Whether hiding from predators, or avoiding battlefield casualties, camouflage is widely employed to prevent detection. Disruptive coloration is a seemingly well-known camouflage mechanism proposed to function by breaking up an object's salient features (for example their characteristic outline), rendering objects more difficult to recognize. However, while a wide range of animals are thought to evade detection using disruptive patterns, there is no direct experimental evidence that disruptive coloration impairs recognition. Using humans searching for computer-generated moth targets, we demonstrate that the number of edge-intersecting patches on a target reduces the likelihood of it being detected, even at the expense of reduced background matching. Crucially, eye-tracking data show that targets with more edge-intersecting patches were looked at for longer periods prior to attack, and passed-over more frequently during search tasks. We therefore show directly that edge patches enhance survivorship by impairing recognition, confirming that disruptive coloration is a distinct camouflage strategy, not simply an artefact of background matching.
authors.affiliation: Department of Biology, Carleton University, , Ottawa, Canada , K1S 5B6.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Webster
authors.forename: Christopher
authors.initials: C
authors.lastname: Hassall
authors.forename: Chris M
authors.initials: CM
authors.lastname: Herdman
authors.forename: Jean-Guy J
authors.initials: JG
authors.lastname: Godin
authors.forename: Thomas N
authors.initials: TN
authors.lastname: Sherratt
mesh_terms: D000220:Adaptation, Biological / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal; D003116:Color; D003118:Color Perception / Q000502:physiology*; D005133:Eye Movements; D006801:Humans; D009036:Moths / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010858:Pigmentation; D011235:Predatory Behavior / Q000502:physiology; D014197:Trees; D014785:Vision, Ocular; D014796:Visual Perception
keywords: background matching; crypsis; disruptive coloration; edge detection; eye tracking; vision