For most of us, the word "chicken" spells a cold, clammy slab of plastic-wrapped white meat plucked out of the refrigerated section of our local supermarket. But in the ancient world, and in many cultures today, chickens had deep religious and social significance.

Speaking from his home in North Carolina, Andrew Lawler, author of Why Did the Chicken Cross the World: The Epic Saga of the Bird That Powers Civilization describes how fried chicken has its origins in West Africa, why the Puritans tried to ban the word "cock," and how the backyard chicken movement is bringing roosters to towns and cities all over America.

Andrew, you know what my first question has to be: Why did the chicken cross the world?

The answer's actually quite simple. The chicken crossed the world because we took it with us. Humans can't do without chickens. Chicken is the most popular meat today. Americans eat more than 80 pounds a year, more than pork or beef. So we tend to think people must have domesticated the chicken because it was good to eat, right? Well, no. Scientists now believe chickens were not domesticated to eat in the first place.

Every chicken you see on Earth is the descendant of the red jungle fowl, a very shy jungle bird that lives in south Asia, all the way from Pakistan to Sumatra and Indonesia. It's a small, pheasant-like bird hunters like because it's very hard to find, so it poses a great challenge. The strange thing is that these birds are so shy that when they're captured in the wild, they can die of a heart attack because they're so terrified of humans. So the question is, How did this bird, that is incredibly shy, become the most ubiquitous bird on Earth?

You suggest that the evolution of the chicken has powered human civilization—that's a pretty big claim. Justify it.

It is a big claim, and I would not have made it when I first started looking into the chicken. Like most people, I thought of it as a bird that provides us with meat and eggs but not much else. But when I started to dig into it, I discovered that the chicken has actually played more roles across human history, in more societies, than any other animal, and I include the dog and the cat and cows and pigs. The chicken is a kind of a zelig of human history, which pops up in all kinds of different societies.

If you go back to ancient Babylon, about 800 B.C., in what is now Iraq, you find seals used by people to identify themselves. Some of these have images of chickens sitting on top of columns being worshipped by priests. That expanded with the Persian Empire. Zoroastrians considered the chicken sacred because it crowed before dawn, before the light appeared. And in Zoroastrian tradition, the coming of the light is a sign of good. So the chicken became associated with an awakening from physical, as well as spiritual, slumber.

I had no idea that chicken soup and the flu vaccine have something in common. So Jewish mothers were right?

Absolutely. There have been several scientific studies in the past decade or so that show quite clearly that chicken soup contains something that helps us get over a cold. It won't cure your cold. But it will definitely help take care of some of those symptoms, like a runny nose or fever. In the ancient world, the chicken was considered a kind of two-legged pharmacy. If you had diarrhea, if you were depressed, if you had a child who was a bed wetter, you name it, there was some part of the chicken that could cure you.

Culturally, you explain that both African-Americans and women were at the forefront of the chicken and egg farming industry in the U.S.—why is that?

When slaves were brought here from West Africa, they came with a deep knowledge of the chicken, because in West Africa the chicken was a common farm animal and also a very sacred animal. The knowledge that African-Americans brought served them very well, because white plantation owners for the most part didn't care much about chicken. In colonial times there were so many other things to eat that chicken was not high on the list.

Whites felt chickens weren't important, so they were often the only animals slaves were allowed to raise in places like Virginia and South Carolina. They would raise chickens and sell them to their owners or to other slave owners. As a result, the chicken business became dominated by African-Americans. Most cooking on the plantations was also done by African-American women.

So whites began to eat more chicken. They also began to like fried chicken. Most people agree that West Africa was a center of this cuisine, where you would fry chicken parts in palm oil. And the slaves brought that tradition to the South. Over time it became one of the most important cuisines of that region.

View Images This vintage poster shows 52 breeds of chickens. Despite being shy in the wild, chickens became the most ubiquitous bird on Earth. Photograph by GraphicaArtis, Getty

Urban chickens are a new fad—sometimes a controversial one. What are the issues?

There's a backyard chicken movement that has started to take off in a lot of cities. There have been numerous legal battles. People who don't want chickens in their neighbors' yards—people who don't want roosters crowing before dawn. There's been a lot of antipathy among some people, who feel farm animals don't belong in the city.

But in the past four or five years, the chicken has begun to triumph in American cities and towns, as they relax their regulations prohibiting farm animals, specifically hens, from backyards. This goes hand in hand with the back-to-the-farm movement, the idea of being of "locavore." Backyard chickens are providing people with a clear and simple way to connect with what lands on their plate.

We have some friends who have free-range chickens. They thought they were just getting eggs, but they're getting a number of other benefits: They have no slugs in their garden, no mosquitoes and no ticks in their yard. What else do chickens do that are good for us?

As I said before, I think one of the most important things that chickens can do for us urban folk is to remind us where our food comes from. In earlier times chickens ate the scraps that the housewife threw out the door after dinner. The chickens took care of insects. In West Africa, they were important for exterminating pests. So chickens were welcome around the house, unlike, say, pigs and cows, which traditionally were kept farther away from dwellings. When archaeologists study ancient sites in the Middle East, they find chicken bones right in the living area. That's because the chicken does a lot of things for us. It cleans things up, gets rid of bugs, and provides us with those eggs we like to have for breakfast.

Do roosters really have no penis?

This is true. And the odd thing about it, of course, is that roosters are the byword for the male reproductive organ. Yet they don't have penises. Ducks and a lot of other birds do. But chickens are among those birds that don't need a penis. When two chickens get romantic, they have a cloacal "kiss," pressing their cloaca against one another. The reason the rooster has been for so long the symbol for sex as well as the male organ is because they're randy creatures. They will mate continuously, and with different partners. In the ancient world, that was considered a sign of vibrancy and fertility. So they became associated with human sex.

In Puritan America, we tried to stamp the word "cock" out of our English language. It used to be you would call a weathervane a weathercock or a water spigot, a water cock. But in the 17th and 18th centuries in New England, people decided that they shouldn't even use the word cock, because it was too suggestive. [Laughs] Luckily, it didn't catch on.

What about the dangers of chickens in the form of avian flu? Are we heading for a human pandemic?

One of the tradeoffs we've made is that animals we domesticate pass on their diseases to us. Pigs and cattle, as well as chickens, have given us things like the flu and the common cold and all kinds of other even more severe diseases.

When it comes to the chicken flu we read about in Asia, there's no question chickens can be a vector. Mostly, these viruses stay within chickens, so they're mainly a threat from one chicken to another. Can chickens give diseases to humans? The answer is yes. And in our modern world it's very easy for a virus that begins in a remote village in Thailand to come to our schools here in the United States. So, it's certainly something to worry about.

But I think we've made the calculation that while the chicken can be a vector for disease, we need the chicken. In a world that's increasingly urban, particularly in places like South America and China, we need the chicken to feed ourselves. If you took the chicken away tomorrow, there would be devastating economic consequences.

It's the festive season. What's the relationship between chickens and turkeys?

When Hernán Cortés, the Spanish conquistador, arrived in Mexico, he described this very large chicken people raised and ate. Scholars have puzzled over that. But it's pretty clear that Cortez was describing the turkey. There's some evidence chickens may have been brought across the Pacific by the Polynesians to South America. But it's disputed how old the chicken bones that are part of this debate are.

What's clear is that before Columbus arrived, there were almost no chickens in the Americas. So Native Americans had to make do with other birds, the turkey being the most prominent. It was widely domesticated in North America, both in Mexico and what is now the U.S., in the pre-Columbian era. But turkeys are quite different. They don't have the growth rate of chickens, and they've never really had the kind of ritual significance chickens had across the ancient world. They also didn't have the fighting gumption you find with chickens.

Do you keep chickens yourself?

I do not. I have friends who have chickens, but my lifestyle is such that, given my travel, I can't have a coop in my backyard, although people in my town are pretty pro-chicken. Nevertheless, I prefer to visit my chickens, rather than feed them every morning.