Dominance and eye colours

[Small Heavens]

Hey all

I keep clownfishes that have black eyes but generally, when the male feels pressured by the female, its eyes turn from black to soft golden or bright golden (depending on how much pressure is going on).
There seem to also be a change to the shape or position of the iris, as if it or the lens becomes more concave or convex as well. Does this happen to all fishes or clownfishes but perhaps just appear more apparent on these fishes because they have black eyes?

Regards ~ Sofie

 

[Planetmacro]

Do you post stupid nonsense to seek attention?

 

[Small Heavens]

"Planet Macro" is an actual army of trolls, don't feed it.

 

[Small Heavens]

Anyway:

Does anybody know if the eye colour associated with submission is induced mechanically or chemically ?