Big Enough

PBS Premiere: June 28, 2005Check the broadcast schedule »

The Height Gap


Anthropometric history was largely a field of two in those years: Steckel and Komlos, with other graduate students conducting studies here and there and Fogel orchestrating from the wings. Steckel, after his work on slaves, went on to Union soldiers and Native Americans. (The men of the northern Cheyenne, he found, were the tallest people in the world in the late nineteenth century: well nourished on bison and berries, and wandering clear of disease on the high plains, they averaged nearly five feet ten.) Then he enlisted anthropologists to gather bone measurements dating back ten thousand years. In both Europe and the Americas, he discovered, humans grew shorter as their cities grew larger. The more people clustered together, the more pest-ridden and poorly fed they became. Heights also fell in synch with global temperatures, which reached a nadir during the Little Ice Age of the seventeenth century.

Big Enough: Measuring the height of children at a migrant workers camp. National Archives and Records AdministrationMeasuring the height of children at a migrant workers camp. National Archives and Records Administration

While Steckel worked backward in time, Komlos worked forward, tracing American and European heights from the seventeenth century on. He was a "modern-day gypsy" at first, he says, moving from archive to archive without tenure or steady funding, wheedling librarians and hiring indifferent research assistants. At the University of Vienna, he tabulated the heights of a hundred and forty thousand Austrian soldiers and their children. At the National Archives in Washington, he studied forty-one hundred and eighty West Point graduates. For thirteen years, he gathered and analyzed the heights of thirty-eight thousand French soldiers from the late seventeen-hundreds. Peasant conscripts were nearly three inches shorter than their well-bred officers -- reason enough for a revolution.

"See this?" Komlos said one afternoon, sliding a sheet of paper toward me. "This one graph took me nine years." We were sitting at his desk at the University of Munich, following his results from century to century and from continent to continent. To either side of us, floor-to-ceiling bookshelves held bound volumes of statistics. High curtainless windows looked out on the triumphal arch of the Siegestor and flooded the room in pale golden light.

It was an odd setting, Komlos admitted, for a Jewish scholar who once nearly starved under the Nazis, but hardly unpleasant. Economic historians with his training are a rarity in Germany, and much valued. As a full professor, Komlos has the equivalent of an endowed chair, with state-sponsored grants for his research. He teaches his courses in English, sends his two sons to an international school, and edits his field's only journal, Economics and Human Biology, also in English. "We live in a little American enclave," his wife, Lillian, told me. But they depend on Europe for their livelihood.

The graph in question showed the heights of American slaves, servants, soldiers, and apprentices in the early seventeen-hundreds. To produce it, Komlos searched through Colonial newspapers for descriptions of runaways and deserters, until he had gathered ten thousand seven hundred and forty-two heights. "You can drown in these data," he said. "But they also allow you to get closer to these guys." He showed me an ad from the Pennsylvania Gazette, dated September 26, 1771. An Irish servant named Nathaniel Anster had run away for the third time. He was thirty years old, with a sandy complexion and short bushy hair. He had on a felt hat and a striped blanket coat, was "much inclined to strong drink," and had "a natural propensity to steal." He was also five feet seven inches tall. When Komlos had gathered enough heights, he averaged them out and plotted them on this graph.

The immediate point was clear: America was a good place to live in the eighteenth century. Game was abundant, land free for the clearing, settlement sparse enough to prevent epidemics. On Komlos's graph, even the runaway slaves are five feet eight, and white colonists are five feet nine -- a full three inches taller than the average European of the time. "So this is the eighteenth century," Komlos said, slapping the files. "This is not problematic. It shows that Americans are well nourished. Terrific." He reached into a cardboard folder and pulled out another series of graphs. "What is problematic is what comes next."

Around the time of the Civil War, Americans' heights predictably decreased: Union soldiers dropped from sixty-eight to sixty-seven inches in the mid-eighteen-hundreds, and similar patterns held for West Point cadets, Amherst students, and free blacks in Maryland and Virginia. By the end of the nineteenth century, however, the country seemed set to regain its eminence. The economy was expanding at a dramatic rate, and public-hygiene campaigns were sweeping the cities clean at last: for the first time in American history, urbanites began to outgrow farmers.

Then something strange happened. While heights in Europe continued to climb, Komlos said, "the U.S. just went flat." In the First World War, the average American soldier was still two inches taller than the average German. But sometime around 1955 the situation began to reverse. The Germans and other Europeans went on to grow an extra two centimetres a decade, and some Asian populations several times more, yet Americans haven't grown taller in fifty years. By now, even the Japanese -- once the shortest industrialized people on earth -- have nearly caught up with us, and Northern Europeans are three inches taller and rising.

The average American man is only five feet nine and a half -- less than an inch taller than the average soldier during the Revolutionary War. Women, meanwhile, seem to be getting smaller. According to the National Center for Health Statistics -- which conducts periodic surveys of as many as thirty-five thousand Americans -- women born in the late nineteen-fifties and early nineteen-sixties average just under five feet five. Those born a decade later are a third of an inch shorter.

Just in case I still thought this a trivial trend, Komlos put a final bar graph in front of me. It was entitled "Life Expectancy 2000." Compared with people in thirty-six other industrialized countries, it showed, Americans rank twenty-eighth in average longevity -- just above the Irish and the Cypriots (the Japanese top the rankings). "Ask yourself this," Komlos said, peering at me above his reading glasses. "What is the difference between Western Europe and the U.S. that would work in this direction? It's not income, since Americans, at least on paper, have been wealthier for more than a century. So what is it?"

The obvious answer would seem to be immigration. The more Mexicans and Chinese there are in the United States, the shorter the American population becomes. But the height statistics that Komlos cites include only native-born Americans who speak English at home, and he is careful to screen out people of Asian and Hispanic descent. In any case, according to Richard Steckel, who has also analyzed American heights, the United States takes in too few immigrants to account for the disparity with Northern Europe.

In the nineteenth century, when Americans were the tallest people in the world, the country took in floods of immigrants. And those Europeans, too, were small compared with native-born Americans. Malnourishment in a mother can cause a child not to grow as tall as it would otherwise. But after three generations or so the immigrants catch up. Around the world, well-fed children differ in height by less than half an inch. In a few, rare cases, an entire people may share the same growth disorder. African Pygmies, for instance, produce too few growth hormones and the proteins that bind them to tissues, so they can't break five feet even on the best of diets. By and large, though, any population can grow as tall as any other.

This last point may sound counterintuitive. Height, like skin color, seems to vary with geography: we think of squat Peruvians, slender Masai, stocky Inuit, and lanky Brazilians. According to Bergmann's Rule and Allen's Rule, animals in cold climates tend to have larger bodies and shorter limbs than those in warm climates. But though climate still shapes musk oxen and giraffes -- and a willowy Inuit is hard to find -- its effect on industrialized people has almost disappeared. Swedes ought to be short and stocky, yet they've had good clothing and shelter for so long that they're some of the tallest people in the world. Mexicans ought to be tall and slender. Yet they're so often stunted by poor diet and diseases that we assume they were born to be small.

Next » | "If there is an answer to the riddle of American height, it probably lies in Holland, where everyone has a theory about stature..."