In testing a hypothesis that "territorial defense in European robins is a fixed action pattern that is released by the sight of orange feathers," researchers found that robins defended their territory by attacking anything that was of similar size and had an orange patch. What experiment would you perform next to determine that the color initiated the defense response?
A) Repeat the experiment using a blue patch instead of an orange patch.
B) Repeat the experiment by removing the patch completely.
C) Repeat the experiment by using a model of a robin that was twice the size of a normal robin but with a small orange patch.
D) Repeat the experiment by using a model of a robin that had an orange patch that was twice the size of a normal patch.

Question

Quizplus · Accepted Answer

This experiment would allow the researchers to determine if the orange color specifically initiated the defense response, as opposed to just any color patch. If the robins do not respond to the blue patch in the same way as they did to the orange patch, it would strongly suggest that the color orange is the specific cue that triggers the fixed action pattern of territorial defense.

In Testing a Hypothesis That "Territorial Defense in European Robins