All applicants to Harvard are ranked on a scale of one to six based on their academic qualifications, and athletes who scored a four were accepted at a rate of about 70 percent. Yet the admit rate for nonathletes with the same score was 0.076 percent—nearly 1,000 times lower. Similarly, 83 percent of athletes with a top academic score got an acceptance letter, compared with 16 percent of nonathletes. Legacy admissions policies get a lot of flak for privileging white applicants, but athletes have a much bigger effect on admissions, and make up a much bigger percentage of the class. And it’s not just Harvard—in 2002, James Schulman and former Princeton University President William Bowen looked at 30 selective colleges and found that athletes were given a 48 percent boost in admissions, compared with 25 percent for legacies and 18 percent for racial minorities.

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Put another way, college sports at elite schools are a quiet sort of affirmative action for affluent white kids, and play a big role in keeping these institutions so stubbornly white and affluent. What makes this all the more perplexing, says John Thelin, a historian of higher education at the University of Kentucky, is that “no other nation has the equivalent of American college sports.” It’s a particular quirk of the American higher-education system that ultimately has major ramifications for who gets in—and who doesn’t—to selective colleges.

When it comes to college athletics, football and basketball command the most public attention, but in the background is a phalanx of lower-profile sports favored by white kids, which often cost a small fortune for a student participating at a top level. Ivy League sports like sailing, golf, water polo, fencing, and lacrosse aren’t typically staples of urban high schools with big nonwhite populations; they have entrenched reputations as suburban, country-club sports. According to the NCAA, of the 232 Division I sailors last year, none were black. Eighty-five percent of college lacrosse players were white, as well as 90 percent of ice-hockey players.