Wednesday, March 02, 2005

285: Experimental evidence on the evolution of camouflage

Disruptive coloration and background pattern matching:
Here we test two key predictions: that patterns on the body's outline should be particularly effective in promoting concealment and that highly contrasting colours should enhance this disruptive effect. Artificial moth-like targets were exposed to bird predation in the field, with the experimental colour patterns on the 'wings' and a dead mealworm as the edible 'body'. Survival analysis supported the predictions, indicating that disruptive coloration is an effective means of camouflage, above and beyond background pattern matching.
This is evolutionary because recognizing food and seeing through camouflage are evolved responses. Camouflage updates as predators learn to detect camo. These are results that can go back into understanding real moths.