Presentation on theme: "Genetics and Race. What is generally agreed upon by the scientific community on the issue of race. Human civilization originated from Africa, mostly likely."— Presentation transcript:
Genetics and Race
What is generally agreed upon by the scientific community on the issue of race. Human civilization originated from Africa, mostly likely Tanzania and Ethiopia, and spread around the globe. "The accident of the predominance of white men in modern times should not give us supercilious ideas about color or persuade us to listen to superficial theories about the innate superiority of the white-skinned man. Four thousand years ago, when civilization was already one or two thousand years old, white men were just a bunch of semi-savages on the outskirts of the civilized world. If there had been anthropologists in Crete, Egypt, and Babylonia, they would have pronounced the white race obviously inferior, and might have discoursed learnedly on the superior germ-plasm or glands of colored folk." Joseph McCabe
New DNA evidence suggests "African Eve", the 150,000-year-old female ancestor of every person on Earth, may have lived in Tanzania or Ethiopia. BBC News April 2, 2003.
Humans moved across continents and established themselves in other regions, whereupon Darwinian adaptation occurred creating phenotypically distinguishable subpopulations with different skin tones, musculature, hair texture, facial characteristics, immune responses, and disease sensitivity.
During the 19th and 19th century human populations were classified into races based on physical characteristics, as if each racial group was pure to form, and there were also claims that the groups evolved separately. Most commentators agree that these so-called scientific taxonomies were designed to place white Europeans at the top of the order of nature.
The celebrated naturalist, Linneaus (1708– 1778), for instance, listed four races, according to continent, namely: (1) European (white), (2) African (black), (3) Asiatic (yellow), and (4) American (red). Blumenback, in 1775, added a fifth type, the Ocieanic or brown race. This classification is still used in some grammar school Geographies, where the races of man are tabulated as: Ethiopian (black), Caucasian (white), American (red), Mongolian (yellow) and Malayan (brown).
During the year 1800, the French naturalist, Cuvier, announced the hypothesis that all ethnic types were traceable to Ham, Chem and Japhet, the three sons of Noah. After that date race classification developed into an amazing contest; a struggle which still rages. By 1873, Haeckel had found no less than twelve distinct races of mankind; and to show the indefatigable nature of his researches, he annexed twenty-two more races a few years later, bringing the grand total of human types up to thirty-four. Deniker, in 1900, presented to the world a very imposing system of race classification. He conceived of the human species existing in the form of six grand divisions, seventeen divisions and twenty-nine races. And despite all this industry among anthropologists, ethnologists and the like, there is yet no agreement on the classification of races. Where one anthropologist finds three racial types, another can spot thirty-three without the least difficulty. John G. Jackson, 1939 (anthropologist) “Ethiopia and the Origin of Civilization.”
Before the civil war, states had laws that defined who was part of the “Negro” of African race. So many children were born when slavemaster’s raped their women slaves that the states had to figure out who was property. Some states used the 1/8th rule (Great Grandfather) others the 1/16th rule (great great grandfather). You could change your race by crossing state lines. By what logic would you classify a person as African if the only blood African was a great-great grandmother, while 15 other ancestors were white. Why not reverse it; one white great great grandmother and 15 Africans?
For over 60 years scientists have reached a consensus that there is no scientific definition of race. The concept of race is viewed as a social construction—a concept whose meaning varies according to cultural trends, history, power among groups, xenophobia, racism and colonialism.
Failure of the Concept of Race “The classification [of humans] into races has proved to be a futile exercise ofor reasons that were already clear to Darwin.” While is is clear there is only one human species, there are no objective reasons for splitting or lumping at any lower taxonomic level (i.e. subspecies, races, varieties). Cavalli-Sforza et al. 1994
Even as the meaning of race has no scientific merit, race has become an important part of public policy; there are scientific studies where the independent variable is race; as it is self- defined. Self-defined concepts of race have a certain plausibility. A person might define themselves as “black” because others treat him/her that way. So race is reduced to how you are perceived or more correctly, how one perceives the way he or she is perceived by others.
How can we justify mapping a dichotomous variable (white vs black) on a continuous variable—like skin color; hair texture etc. or even allele frequencies? Can ancestry genetics be a substitute for defining race? Does it change the way science views race?
Can we use self-defined concepts of race to make important health decisions? BiDil was the first drug approved by the FDA for a particular self-defined racial group. Doctors however, do not ask a patient what race are you. They observe and infer and prescribe. A self-defined concept of race is correlated with drug efficacy. A socially constructed concept is the independent variable correlated with a biological endpoint—namely healthy heart (rate of myocardial infarction). Is it possible for a socially defined concept to give high correlation with a real biological mechanism? If so what is the mechanism? It can’t be skin color since some people who identify themselves as African American have lighter skin color than others.