When an Incubating Graylag Goose Sees a Nearby Egg-Shaped Object

Essay

When an incubating graylag goose sees a nearby egg-shaped object, a neural network is triggered, causing the bird to go through an egg-retrieval routine consisting of stretching out its neck, tucking the egg under its bill, and rolling the egg carefully back to the nest. In this example, identify the sign stimulus, the fixed action pattern, and the innate releasing mechanism.