Why Did the Chicken Cross the World? (19 page)

“They have fallen in price because they were unnaturally exalted,” one of Watts's last articles states. But she confidently predicted that large and fast-laying birds “shall now be within the reach of all.” Breeding the Asian birds with local varieties like the small and ornery Dorking soon gave chickens an advantage over the geese and ducks long favored in medieval England. They could eat a wider variety of food, were amenable to living in small spaces, and produced more eggs over a longer period of the year. They were also gentler than geese and provided much more meat than a dove. Even the stuffy
Times
saw the possibilities. “If the Cochin China breed will really give us poultry of a finer and cheaper description than we have had before,” the paper stated, “the ‘mania' will have done its proper work.”

7.

The Harlequin's Sword

Amidst the immense number of different breeds of the gallinaceous tribe, how shall we determine the original stock? So many circumstances have operated, so many accidents have occurred; the attention, and even the whim of man have so much multiplied the varieties, that it appears extremely difficult to trace them to their source.

—Comte de Buffon,
The Natural History of Birds

T
he bird curator at the Natural History Museum gives me a dubious look. “No one comes to see Darwin's chickens,” Joanne Cooper says. The ugly concrete annex attached to an old Victorian building in Tring, a village north of London, is the Vatican of ornithology, where a reluctant and eccentric banker named Baron Lionel Walter Rothschild collected more than 2 million specimens and a hundred thousand species of butterflies and birds before he died in 1937. Now public, the museum houses three hundred thousand bird skins obtained primarily during the heyday of the British Empire as well as thousands of skeletons and stuffed birds from around the world.

Cooper, wearing a ponytail and glasses, guides me through security and down the bare corridors. Over her shoulder she tells me that
researchers interested in Darwin typically ask to see the finches the naturalist collected in the Galàpagos Islands during his HMS
Beagle
expedition or the pigeons that he later bred and studied as part of his effort to understand the workings of evolution. His 1859 book
On the Origin of Species
begins by discussing pigeons, and he dwells at length on the minute differences in the beaks of the South American finches.

Largely forgotten are the chicken carcasses that he donated to the museum a century and a half ago, as well as the story they tell of how the common fowl helped the naturalist clinch his controversial theory. In the midst of The Fancy and encouraged by one of its leading figures, Darwin sought specimens of the fowl from around the world, carefully studied their attributes, and waded into the heated debate about what made the chicken the chicken.

Modern chicken research is dominated by challenging but narrow goals as scientists try to eke out an ounce more meat from a pound of feed, prevent disease transmission in a warehouse crammed with tens of thousands of birds, or figure out an inexpensive method to determine if an egg will produce a hen or a rooster. In the mid-1800s, the field was crowded with theologians, philosophers, and amateur breeders as well as biologists. Chickens were at the heart of the bitter culture war pitting atheists against believers and abolitionists against slavery advocates.

The bird's modern identity took shape a century earlier in the Scandinavian town of Uppsala, where Carolus Linnaeus, a Swedish naturalist, was fascinated with the fowl. This central figure of the Enlightenment, a small-town university professor adored by Voltaire, Goethe, and Rousseau, kept a small flock in his large garden behind the modest two-story house that still stands on a corner on the old town's outskirts. Students crowded into his spacious and sunny study on the second floor to hear his lectures, and he occasionally discussed the bird's many medicinal and culinary properties, describing various Swedish breeds, recounting chicken folklore, and explaining how to neuter a cock.

When he created his system of taxonomy, which we still use today, he put the domestic chicken together with a wild variety said to live
at the mouth of Southeast Asia's Mekong River—an early reference to what we now call the red jungle fowl.

In Linnaeus's animal kingdom, the chicken falls into the phylum Chordata, since it shares, with humans and other vertebrates, a backbone. The class is Aves, the collection of ten thousand species we call birds. Galliformes is their order, a group that includes a host of heftier species like turkeys that prefer the ground to the air. Their extended family is Phasianidae, which includes all pheasants and partridges and quail and peafowl, lumped together because they share a certain look that includes spurs on their legs, squat bodies, and short necks. Four sorts of jungle fowl fall into the more intimate subfamily Phasianinae, along with such charmingly named birds as the ­Tibetan-Eared, the Mikado, and Mrs. Hume's pheasant.

The genus
Gallus
—the Latin word for rooster—consists of four sibling species of jungle fowl. Red jungle fowl and chickens form a single distinct species,
Gallus gallus
, though some biologists give the barnyard bird the name
Gallus gallus domesticus
.

By putting a wild and domesticated bird together, Linnaeus was not suggesting that the chicken evolved from the wild one, only that they were similar enough that one could breed with the other. “God created, Linnaeus organized,” he explained. Like most Europeans of his day, Jews and Christians alike, Linnaeus adhered to the belief that God made wild as well as domesticated plants and animals during the first week of creation, as recounted in the biblical book of Genesis. Species, therefore, did not change. Horses and donkeys might mate, for instance, but the resulting mule would never have its own progeny.

The French naturalist Georges-Louis Leclerc, also known as the Comte de Buffon, was one of the few in that era to challenge Genesis—and Linnaeus—publicly. Though both men were born in 1707, they lived in radically different worlds. The French count was a high-living Parisian aristocrat who wrote a natural history that scandalously suggested a much older earth than outlined in scripture. His connections and charm in prerevolutionary France kept him safe from the clerical authorities. Buffon did not directly challenge the
idea of fixed species, but he thought that Linnaeus's system was too arbitrary and confining. Within a species, he pointed out that enormous variation was possible, citing “the Laplander, the Patagonian, the Hottentot, the European, the American, and the Negro,” among humans.

The varieties of chickens, he noted, were even more pronounced. There was one Asian variety of poultry, Buffon had heard on good authority, with bones “as black as ebony.” This is an early reference to the Hmong chicken found in south China and Vietnam that has not just black feathers but black meat and blood and is prized for its taste and medicinal properties. Buffon believed that such variation must be the result of human influence and not just the static creation of a supreme being. “The cock is one of the oldest companions of mankind, and . . . among the first which were drawn from the wilds of the forest, to become a partaker of the advantages of society,” he asserted. Wild ones still existed in the forests of India, but he suggested that in many places “the domestic fowl has almost everywhere banished the wild one.” The naturalist all but said that the domesticated bird evolved from a wild creature to a human companion, but didn't explain what mechanism could engender such a transformation.

Not until the year that Darwin was born, 1809, did the concept of change among species capture widespread attention. The French naturalist Jean-Baptiste Lamarck claimed that species could transmute into other species as part of a mysterious force that made life ever more complex. Environment, Lamarck insisted, determines traits: moles don't need eyes nor birds teeth. He argued that an individual animal—say, a giraffe that stretched to reach the leaves of a high tree—could pass on these traits to the next generation. Critics, both colleagues and clergy, pounced on the theory as either flawed or blasphemous. In a clever stunt that drew a lot of publicity, one distinguished French scientist, Georges Cuvier, closely examined animal mummies brought back from Egypt during Napoleon's attempt to conquer the ancient land along the Nile. The ibis and cats were no different from our modern varieties, he noted, incorrectly concluding that species were fixed and that Lamarck was grossly mistaken.

Yet evidence mounted that the world was far older and life far more varied than could be accounted for in the Bible, which, after all, doesn't specifically identify chickens in the Old Testament. A steady stream of living creatures that explorers, conquerors, and colonizers sent back to Europe would have required an unimaginably vast ­Noah's ark. The new science of biology grew up around these specimens. Yet as these discoveries challenged religious beliefs, they also were used to justify slavery.

In the late 1840s, just as dozens of strange and novel Asian fowl varieties spread across Europe and America, some scientists argued that the chicken's remarkable diversity demonstrated that its roots were in more than one ancestor and that humans might have different roots as well. The Philadelphia Quaker and physician Samuel George Morton maintained that chickens and guinea fowl could produce fertile offspring—a claim that later proved dubious—and that blacks and whites, therefore, could do the same and still be classified as separate species. Slavery's supporters in the American South quickly publicized his findings.

A plucky Southerner refuted this claim with his own poultry experiments. The Lutheran minister and amateur ornithologist John Bachman made the case for a single ancestor of all chickens. The Charleston pastor closely observed red jungle fowl in the London Zoo as hen fever raged in Britain. “So nearly did they resemble the domesticated fowl in every particular, that we could scarcely distinguish them from some varieties among our poultry,” he wrote in 1849. His own breeding research on several species of jungle fowl demonstrated that two different species could not produce fertile offspring and concluded that human traits, like those of poultry, might vary considerably within the same species.

Darwin, who, in one of those interesting quirks of history, was born on the same day as Abraham Lincoln, closely followed this contentious debate in scientific proceedings, conferences, and journals. An ardent opponent of slavery since witnessing its awful consequences on his
Beagle
voyage, he was appalled that progressive scientific ideas were interpreted as an excuse for barbarity. Darwin's
insatiable curiosity often overrode the class, race, and professional boundaries typical in his day. He once paid for lessons in taxidermy from an African living in Edinburgh, remembering him as “a very pleasant and intelligent man.”

His open-mindedness extended to species that others considered inferior or unimportant. Darwin spent seven years examining barnacles. Listed in a contemporary directory as “farmer,” he also knew that amateur breeders, whatever their social or financial status, were vital sources of information. So when a devout country rector of modest means but enormous expertise urged him to put away the crustaceans and focus on poultry, he eventually followed the advice. This led Darwin to the hard evidence he needed to make a convincing case for his theory of evolution.

Chickens may outnumber every other kind of bird today, but they get short shrift among ornithologists. “The domesticated specimens are not as valued,” curator Cooper tells me as we pass two elderly women at a wooden table examining stuffed kingfishers from Sudan. “But for Darwin, it was the smaller domesticates that he needed to establish his fundamental principles.” For four frenzied years, at the tail end of The Fancy, the naturalist focused his attention on pigeons and chickens. Small animals that breed quickly in captivity are good models for demonstrating the long-term power of natural selection.

Darwin worked mainly with skeletons rather than skins, Cooper says as we climb the stairwell to the next floor. Skeletons, she explains, are just that, but to prepare skins, “You remove their innards, pop out the brains and eyes, and sew them back up.” We reach the annex floor devoted solely to skin storage, where I lose count of the identical narrow aisles made by double rows of off-white cabinets. The fluorescent lights illuminate a cheery yellow floor, yet the vast room has a sepulchral quality. Without hesitating, Cooper glides down one aisle and pulls open a drawer like those used for lateral hanging files.

Inside are a dozen birds lying in their shared metal coffin, each with a tag on a toe as in a morgue. The skins resemble deflated bal
loons. She reaches for one. “Collected by A. R. Wallace. 1862,” reads the tag. Neat handwriting identifies it as
Gallus bankiva
from Malacca on the Malaysian peninsula. This is a red jungle fowl variety that the naturalist Alfred Russell Wallace encountered near the southernmost native range of the bird, between Singapore and Kuala Lumpur. Wallace independently came up with the theory of evolution while traveling in Southeast Asia, and his writings on the subject were read together with Darwin's at a London meeting in 1858.

In the drawer below are two stuffed red jungle fowl, fresh enough that they seem ready after a century to make a break for the forest. There are dull gray-brown hens and showy roosters lying on their backs, beaks pointed to heaven. The colors of the males in the monochrome surroundings are dazzling. There is a shower of gold around the neck, a magnificent patchwork of royal blue across the body, feathers with a subtle burnt orange brightening to yellow and violet turning to black at the tail. In another drawer, a 1939 specimen is labeled as “Domestic Guinea Fowl x Domestic Fowl.” Another contains hefty chickens with naked necks. A sign on the outside of the drawer explains that they are a breed “periodically featured, incorrectly, in the media as a hybrid between chicken and turkey.” Sometimes species are just species.