Blacks first won the 100 meter dash gold medal in 1932, and again in 1936 and 1948, but whites won the 100 meter dash gold medal in 1952, 1956, 1960, and again in 1972 and 1980.
But from 1984 onward, all 72 finalists in the 100 meter dash have been at least half black.
The simple explanation would be that blacks before 1984 were oppressed by discrimination or malnutrition or whatever so their natural athletic superiority wasn’t revealed. That could well be true.
On the other hand, the opinion of sophisticated liberal sportswriters in the 1950s and 1960s tended to be that whites and blacks were pretty close to equal in athletic ability.
For example, in the mid-1950s, all three New York baseball teams had future Hall of Famers playing centerfield. Duke Snider (white) wasn’t the best, but you could, to this day, have a good argument over who was more talented: Willie Mays (black) or Mickey Mantle (white). Mays averaged 9.1 Wins Above Replacement in his last 5 seasons in New York from 1954-58, but Mantle averaged 9.5.
My vague impression is that it was the arrival of O.J. Simpson at USC in 1967-68 that tipped opinion toward the theory of black athletic superiority.
But here’s an alternative theory that one of my commenters (monicker unfortunately forgotten) has suggested over the years: it’s not that blacks are genetically better at athletic performance, it’s that blacks are genetically better at benefiting from performance-enhancing drugs.
I don’t really know how to decisively test this theory, but it’s one that I haven’t been able to dismiss.