Editor’s Note: Joseph Graves is Professor of Biological Studies at the Joint School for Nanoscience and Nanoengingeering, administered by both North Carolina A&T State University (HBCU) and UNC Greensbroro. The views expressed in this commentary are his own. View more opinion on CNN.

CNN  — 

90-year-old Nobel Prize-winning scientist James Watson is not alone in his racist thinking. In a recent PBS film, Watson alleges that, because of genes, white and black people have different intellectual capacities. You can guess who he thinks is dumber.

As I have learned in my career, there is no correlation between an individual’s scientific achievement and his or her ethical behavior. I routinely encounter individuals who are or were great scientists but remain flawed in regard to their thinking about race. Specifically, I have found it quite common for scientists, including many biologists, to conflate biological and social conceptions of race.

Thus, while the scientific method is objective, the scientific enterprise is not. The latter is carried out by individuals who always have social agendas. Some of them good, but just as often bad.

Dr. Joseph L. Graves Jr.

But back to Watson. His PBS claims weren’t his first bigoted statements. He has routinely reiterated the views of 19th and early 20th century “race science,” which is premised on the idea that different races of humans exist and that their inborn (genetic) qualities determine their intelligence and ability to create and sustain great civilizations.

Where did Watson get those racist ideas? Well, Watson was born into a rigidly segregated society. For much of his life, most biologists and anthropologists perpetuated the notion of race science. Take Sir Francis Galton, who gave the world biostatistics, but also said that some dogs were more intelligent than “Negroes,” an idea which he articulated in “Hereditary Genius, an Inquiry into its Laws and Consequences.”

Galton’s views were shared by both Nazi and some American scientists in the mid-20th century, who agreed on the inferiority of the “Negro.” And that thinking had dangerous effects on policymaking. During World War II, for example, the United States segregated blood supplies by race due to the widely held “scientific” belief that whites were a superior race, and their blood should not mix with that of black Americans.

But Galton wasn’t the only scientist spreading this myth. And it’s highly likely that Watson read the works of people like Frank McGurk, Henry Garrett, Richard Herrnstein and Arthur Jensen – all scholars from distinguished universities claiming that intelligence (IQ) was genetically determined and that whites displayed greater genetic predisposition for this trait than blacks.

Even if Watson didn’t read those writers, he may have arrived at the same conclusion, considering this was a prevailing view in American society. In 1942, only 47% of whites in the United States believed that blacks were of equal intelligence. This value increased to 80% in 1966, but declined to 77% in 1968. In 2008, this value was about the same as that recorded in 1968.

However, the tragedy here is Watson’s intransigence in light of the scientific developments of the late 20th and early 21st century. These developments have demolished both the notion that human beings could be unambiguously partitioned into biological races, and the idea that it is likely that “races” of humans are genetically differentiated in intelligence (however defined).

We also have new genomic tools that allow us to better understand the relationship between genes and the traits that they encode. For example, studies of worldwide genomic variation don’t allow us to unambiguously define racial groups. Furthermore, the studies indicate that our socially-defined races do not correspond to the underlying genetic variation within our species.

There have also been several recent studies that have attempted to identify genetic variants associated with some definition of intelligence or educational attainment. So far, these studies have found that the underlying genomics of these traits are complex – meaning they are coded for by many genes, possibly in the thousands – and are not generally replicable between the different cohorts studied.

And a new study on the genes-to-physical trait relationship makes the entire enterprise of attempting to correlate measured physical traits between human populations and their genetic underpinnings extremely problematic. This study shows that environmental influences can have profound influences on the how the gene-to-physical trait pipeline operates. For example, mutations have been found in fruit flies which have normal function at room temperature, but are lethal to the flies if you attempt to grow them in lower temperatures. Thus, because all genes are influenced by environment (even if not to the extreme of the last example), it is important to know if any two groups you are comparing are experiencing the same environment.

Therefore, when environmental influences are radically different between population groups, especially between those who are socially dominant and socially subordinated, we cannot say that a given physical result is being determined by the genes. This is Watson’s great mistake, in forgetting, or possibly ignoring, that there are strong environmental differences influencing people existing in different portions of a society’s hierarchy.

At the end of the day, though, Watson was a product of his time. He commented on what he saw; huge social differentials between persons of European and African descent. Although, because Watson was a biologist and science has so clearly evolved, his thinking on race should have evolved, too. He should have been able to recognize that there were numerous other explanations for the social conditions of persons of African descent around the world besides genetics.

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    Worst yet, his racism contributes to a pervasive institutional racism still steeped in the United States. I have argued that these conditions are toxic to both persons of African and European descent. Illustrations of that toxicity to African-Americans can be seen in several arenas, including health disparity, educational attainment and mass incarceration.

    The toxicity of racism to persons of European descent results primarily from the amount of energy it requires to maintain social inequality. For example, the cognitive dissonance that is required to, on one hand, believe that all Americans should be treated equally by the law but, on the other, recognize that equality in this country has always been determined by skin color.

    This is the irrationality of racism that can take even the brightest of people down roads that cannot be supported by their higher reasoning. Such is the case of Watson.