How have racial differences evolved?

Although the move out of Africa by modern humans to Europe and Asia occurred rather recently in evolutionary time, scientists now know that in relatively few generations, even small, chance mutations can trigger a chain reaction with cascading consequences resulting in significant racial differences or possibly even the creation of new species. Economic ravages, natural disasters, genocidal pogroms, and geographical isolation caused by mountains, oceans, and deserts, have deepened these differences over time. This is the endless loop of genetics and culture, nature and nurture.

Genetically linked, highly heritable characteristics such as skeletal structure, the distribution of muscle fiber types, reflex capabilities, metabolic efficiency, lung capacity, and the ability to use energy more efficiently are not evenly distributed among populations and cannot be explained by known environmental factors. Scientists are just beginning to isolate the genetic links to biologically-based differences, most notably in isolating the causes of population specific diseases such as Tay-Sachs, which afflicts Jews, and sickle cell, which targets blacks.

Popular thinking still lags this genetic revolution. "Differences among athletes of elite caliber are so small," notes Robert Malina, a Michigan State University physical anthropologist and editor of the Journal of Human Genetics, "that if you have a physique or the ability to fire muscle fibers more efficiently that might be genetically based ... it might be very, very significant. The fraction of a second is the difference between the gold medal and fourth place."

Although scientists are just beginning to isolate the genetic links to those biologically-based differences, it is indisputable that they exist. Each sport demands a slightly different mix of biomechanical, anaerobic, and aerobic abilities. Athletes from each region of the world tend to excel in specific events as a result of evolutionary adaptations to extremely different environments that became encoded in the genes.

Whites of Eurasian ancestry, who have, on average, more natural upper-body strength, predictably dominate weightlifting, wrestling and all field events, such as the shot-put and hammer (whites hold 46 of the top 50 throws). Evolutionary forces in this northern clime have shaped a population with a mesomorphic body type - large and muscular, particularly in the upper body, with relatively short arms and legs and thick torsos. These proportions tend to be an advantage, particularly in sports in which strength rather than speed is at a premium.

East Asians tend to be small with relatively short extremities, long torsos, and a thicker layer of fat, evolutionary adaptations to harsh climes encountered by Homo sapiens who migrated to Northeast Asia about 40,000 years ago. As a result, athletes from this region are somewhat slower and less strong than whites or blacks, but more flexible on average - a key potential advantage in diving and some events in gymnastics (hence the term "Chinese splits") and figure skating. That anthropometric reality severely hampers Asians from being great sprinters or leapers: not one Asian male or female high jumper makes the top 50 all-time. It should come as no surprise that the world's most remarkable ultra-endurance runners, the 4,000 or so Native American Tarahumara of Mexico, have East Asian ancestry.

The cluster of islands that straddle the international date line in the South Pacific, including Somoa and American Somoa, have funneled hundreds of players into American football and Australian rugby. Polynesia is a hotbed of human biodiversity. More than likely, its inhabitants trace their ancestry to southern Asia by way of Africa. Polynesians, especially the Samoans, are amongst the worlds most mesomorphic body types. A number of studies have shown that muscle bulk and the degree of muscularity especially in the thigh and buttock are important predictors of success in rugby players whereas the opposite applies in such sports as distance running. This genetic admixture helps in part explain why athletes from this region are large, agile, and fast.

The Rise of The African Athlete

Africa is the world's sports hothouse. With the breaking of Sebastian Coe's 18-year-old 1,000-meter world record in 1999 by Kenyan Noah Ngeny, every men's world record at every commonly-run track distance belongs to a runner of African descent.


While Africa is the mother-lode of the running world, talent is not evenly distributed across the continent but is concentrated in three areas: a swath of western African coastal states, notably Senegal, Nigeria, and Cameroon, extending south to Namibia; the northern African countries of Algeria and Morocco; and a long stretch of eastern African states from Ethiopia, Tanzania, and Kenya to mountainous South Africa. However, there are a range of structural traits shared by genetically-diverse African athletes: low body fat, longer legs in comparison to the rest of their bodies, and narrow hips.