When it comes to raising an Olympic gymnast, five-tool shortstop, or butterfly specialist, should we put more stock in nature or nurture? Genetics or a fortune in summer instructional camps? Dad’s athletic history or a climate suited to year-round training?

With the Olympics approaching, the last of these questions is particularly interesting. How much of a role does where you grow up play in your chances of excelling at a particular sport? There are some well-defined examples on display at the Olympics. There is evidence that West Africans, and those of West African descent, are blessed with more fast-twitch muscles than, say, French Canadians, which could go at least some way in explaining the success of Jamaicans in sprinting. Kenyan success in distance running might owe less to genetics than to the availability of high-altitude training.

Sports appear, on their surface, to be one of our meritocratic endeavors: if you’re better than the other guy, you’ll get the spot on the team, and the scholarship, and, if you’re still better than the other guy, the professional contract. But it’s not that simple. Why, we like to ask, doesn’t the United States, the biggest, baddest sporting country in the world, dominate everything? We turn it over to our Malcolm Gladwell: “In theory, big countries should dominate all sports because they have the biggest talent pool. But they don’t, because societies squander their talent.”

For a brief diversion, spend some time zooming in and out of these two maps, which plot the birthplace of every player in Major League Baseball and the National Hockey League, respectively. There are a number of unsurprising trends. Baseball has at least one player from every state, but only four from Europe: an Italian, and three American military brats. Latin America is a prime source of talent, but no one hails from anywhere below Venezuela. If there is a center of gravity in the baseball world, it is the Tropic of Cancer. Hockey players, meanwhile, are produced primarily from a pair of circles extending from Prague and Stockholm, and waves going north and south from the U.S.-Canada border. There are fewer and fewer the farther away you get. In fact, there are currently more professional hockey players—one each—from Brazil, Nigeria, and Brunei, than there are from twenty different American states, each of which produced none. Extend the Mason-Dixon Line westward to California and only two dozen professional hockey players have been born south of it.

Six of those players came from St. Louis, which makes some sense to me. Growing up in Kansas City, on the other side of Missouri, nobody played hockey. (We have no current pros.) Kids in St. Louis played hockey, or lacrosse; we played soccer or football. The lines can be drawn even more finely, between, say kids in Kansas City, Kansas, who played soccer, and kids from Kansas City, Missouri, who played football. Some sports managed to cross geographic boundaries, but not many: no matter where you were from, if you were meek, like me, you just gave up and played tennis.

We can at least begin to wonder, then, how much of athletic success is owed to place of birth. Adjusted for population size, Jackson, Mississippi, has produced more current N.F.L. players than any other metro area in the United States. Being born there doesn’t guarantee a Division I football scholarship, but your chances are better than they are in Duluth, Minnesota, where the chance to train, hockey-wise, exists year-round, but no one wants to freeze through blocking drills in February. In the South, and California—the fastest growing home to N.F.L.ers—and any other place where the temperature rarely drops below fifty, the climate is more conducive to year-round two-a-days.

Might, then, Alabamans be inherently better football players than Minnesotans? Can natural sporting selection begin its process in mere decades? Or, conversely, what if there’s some hypothetical quirk of Norwegian blood—call it the Gridiron Gene—that would make a number of northern Minnesotans into solid middle linebackers if only they didn’t start life with skates leaning against their crib? If Alabama decided to throw its resources into hockey, could it produce an N.H.L. All-Star in fifteen years? In an effort to boost its medal count as it prepared to host this summer’s Olympics, Great Britain invested heavily in its track cycling team, and topped the cycling medal chart in Beijing with fourteen, as many as it had won in the previous fifty years of Olympic competition combined. Overcoming regional sporting bias may require a concerted effort like this, which is why it doesn’t seem fair to curse my parents and their genes for my non-existent hockey ability. I just blame them for not moving the family to St. Louis.

Photograph by Bob Leverone/Sporting News/Getty Images.

Reeves Wiedeman is a member of The New Yorkers editorial staff.

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