Four of the five sapient species have widely varying natural skin colours depending on climate. Blood colour also plays a role in determining the exact colour of skin, so all but the darkest climate-variant skin colours still look different depending on species.
Rocca have extraordinarily little variance in skin shade. Since they all live on one Dor Roc continent, the cause of this (intrinsic and/or geographic?) is unknown.
Shade's sapient species are much alike in that they discriminate within their own species, and others, based on skin colour and/or home country, but do not discriminate on the basis of species against anyone of their own country.