1. Answer: It depends on everyone's taste and these rankings change all the time. According to RankMyPorn, at the moment, the top ranked Dark Hair Female Pornstars in the world are: Veronica Leal, Sasha Grey, Aaliyah Hadid, Veronica Avluv, Skyla Novea, Rebeca Linares, Katrina Jade, Aletta Ocean, Rose Monroe, Daisy Marie, but these will change based on what people vote.
2. Answer: It changes. You can see the latest rankings on RankMyPorn.com and also vote on it for free.