You are investigating whether robins prefer one type of bird seed over any type your independent variable is the type of bird seed used what should be your independet variable?

In your investigation, the independent variable is the type of bird seed used, as it is the factor you are manipulating to observe its effect on the robins' preferences. You would need to vary the types of bird seed presented to the robins, such as sunflower seeds, millet, or mixed seeds, to determine which one they prefer. The dependent variable would be the robins' feeding behavior or preference, measured by the amount of each type of seed consumed.