WILD BIRDS PREFER THE FAMILIAR COLOR PATTERN WHEN FEEDING ON SIMILAR ARTIFICIAL MORPHS

Discusses 6 experiments on wild birds feeding on "populations' of 2 similar green "morphs' of an artificial prey which had a single dark green stripe or were plain. Birds foraging on lawns were fed on one type, then given a choice of equal numbers of the two; they were then fed on the 2nd type and again given a choice. Birds tended to prefer the familiar prey, even after shorter training sessions. Results provide evidence for behaviour that could lead to the maintenance of prey polymorphisms in which morphs are differentiated by the presence or absence of inconspicuous patterns. -from Authors