The Biology of Race
We think we know what "race" is.  We use the word all the time.  But nothing about "race" can be taken for granted.  Indeed, we are not really sure if different biological races of humans even exist.

Scientists who are studying this subject report that "race accounts for only a minuscule .012 percent difference in our genetic material." 1  Genes are the basic building blocks of human life.

In other words, under the world's most powerful microscopes, "race" is almost invisible.  The genetic differences between individuals of the same race are far greater than the differences between races – assuming we even agree on what these races are.  Differences that the eye sees as "race" are for the most part skin-deep adaptations to climate, which evolved as humans moved out of the ancestral home of all of us, the continent of Africa .

Race in the United States
If you were asked to name the principal racial groups, what would you say?  It is likely that you would name "white" (or "Caucasian"), "Asian" (or "Mongoloid"). and black ("Negroid").  You would probably assume that racial distinctions are visible to the eye – in the color of skin, type of hair and features.

So how then can we make sense of this case which appeared before a court in Louisiana in 1982-3?  Susie Guillory Phipps looked "white" and lived as a white woman in a family with several blond, blue-eyed members.  She was, however,   denied a passport because she had checked "white" on her passport application!

Her problem was that her birth certificate gave her race as "colored."  The midwife at her birth had written colored based on information that the family had "colored" blood.  It turned out that she was the great-great-great-great granddaughter of a French landowner and a woman of African descent whom he made his mistress in 1770 – that is, before the American Revolution.  Two hundred years later, in 1970, the Louisiana legislature passed a law (statute 42:267) that says a person is "Black" or "colored" if his or her ancestry is more than one thirty-second black.  Appearance has nothing to do with it. 

When Susie Phipps petitioned the state district court to have the status on her parents' birth certificates changed to "white" so she and her brothers and sisters could change their birth certificates to "white" as well, the district court and then the state appeals court refused.  The judges said that racial designations could not be changed, and that "colored" was Mrs. Phipps' correct classification because she was 3/32 black.  In 1986, three years after the Louisiana law was repealed because of the negative publicity which the Phipps case attracted, both the Louisiana Supreme Court and the US Supreme Court refused to review or reverse this lower court ruling. 

If race isn't something you see when you look at a person like Susie Phipps, and if you have trouble detecting it under a microscope, what is it?  Different countries disagree on how to define it.  Only the United States defines a person with a drop of "black blood," a trace of African ancestry, as "Black."  No other country uses what has been called the "one drop rule" as a defining criteria of who is Black.