system
Given the following post, respond as if you're commenting on Reddit:
human
Do the pupils of heterochromic people contract and retract at different rates? Does eye color affect the speed at which your pupils contract/retract?
gpt
Not at all. Eye color is just basically the pigment present in the iris. 

Also some clarification on ophthalmologic terminology, pupils don’t “contract” - they “constrict”. They don’t “retract” either. You probably mean “constrict” and “dilate” as you’re referring to the pupils.

“Contract” is a generic term for a muscle’s action, while “retract” is term used for the eyelid (e.g. Lid retraction, or pulling up your eyelids - the action of your levator palpebrae superioris muscle).

Now going back to your question, do the pigments in the iris change pupillary dilatation/constriction? Nope. Not at all. Dilatation/constriction are regulated by reflex arcs, controlled by the ANS (autonomic nervous system). Your oculomotor nerve is responsible for constriction, while sympathetic nerves control dilation. The iris’ pigment has absolutely no relevance with the reflex arcs/nerves. 

Hope this helped!