Summary: Skelhorn (2011)

Noxious prey may use conspicuous colour patterns to advertise their defences (chemical or physical) to predators (aposematic colouring) and predators may show unlearned biases against these warning colours. Predators may use additional signals (.e.g sounds and odours) to determine attack rate and may decreases attack rates when the risk of ingestion toxic prey is perceived to be high. If a cue reliably signals prey defense, this should incite biases by predators against warningly coloured food. Skelhorn (2011) tested whether observation of a conspecific's distaste response to a bitter-tasting solution (e.g. beak wiping, head shaking) caused chicks (Gallus gallus) to bias their foraging decisions away from warningly colour prey. Chicks that observed a distaste reaction attacked fewer red and yellow crumbs, and more green crumbs. Observing a disgust response caused observers to bias their foraging preferences away from warningly coloured food. Skelhorn (2011) suggests that a predator's social system may be important in the evolution of prey defences.