It is in America, inasmuch as the "one drop rule" has been grandfathered in and nobody has thought to challenge it yet (speaking of inherently racist traditions, try looking up the origin of the phrase "grandfather clause").No, no they're not. A black person is not made black by the colour of their skin
Yet it still remains the case that "race" and "ethnicity" remain distinct concepts: the former is describing appearance, the latter is describing lineage and origin.
It's a question of definition, not basis. A person whose height is significantly greater than the average person in that country is called "a tall person." By the same token, a person whose skin is significantly darker than that of an American of Anglo-Saxon descent would is generally called "a black person." Beyond that basic descriptions of relative height or skin color, those two categories are almost totally arbitrary, if not meaningless.The idea that it has any basis in human anatomy or biology is obsolete