I was wondering if someone with more of a back ground in animal biology might answer a question I have.
Do non-circular (elongated) iris's provide the animals that have them a greater range of view along the axis of the elongation, or it does the shape just create an easier musculature for opening and closing the iris?
Like cat eyes are elongated along the vertical access. Does this grant them a larger field of view up and down?
Or goats have an elongated iris horizontally. Does this provide a larger horizontal field of view?