Lesser Beasts: A Snout-to-Tail History of the Humble Pig (4 page)

What started as a hunting strategy became, over hundreds or thousands of years, a new relationship with goats. Hunters followed the herds through the hills, closely observing them, learning their behavior, and selectively culling them to maximize docility and productivity. In time, hunters gave way to shepherds, who controlled their precious livestock with fences and herding dogs.

A similar domestication process is likely for sheep and cows—but not for swine. Omnivorous and intelligent, pigs demand a different theory of domestication, one that accounts for the ways they manipulated people.

W
ild boars,
Sus scrofa
, became domestic pigs,
Sus scrofa domesticus
, several times, independently. It happened once along the Yellow River in China and perhaps a second time along the Yangtze sometime before 6000
bc
.
It’s also likely that pigs were domesticated in India and Southeast Asia. The occasion we know most about happened in the Near East, starting at Hallan Cemi, roughly 11,000 years ago.

When something happens a half dozen times or more, it starts to take on an air of inevitability, as if the partnership between pigs and people had been rendered necessary by the nature of each. The habits of wild pigs had not changed much in the few million years before domestication. The same cannot be said of people: after the last great ice age, they had stopped wandering in search of food and settled down into villages. Not long afterward, pigs joined them.

The process of pig domestication didn’t happen as it did with goats because wild boars aren’t much like wild goats. Pigs group themselves not in large herds but in small maternal family groups, known as sounders, averaging a dozen or so individuals. And they live not on open hillsides but in the forest. To hunt them, humans likely sat quietly and waited for one to wander down the path. Boars couldn’t be followed, observed, and selectively killed. Boar hunting could not have turned into boar herding.

A different mechanism was at play, and the story of how wolves turned into dogs might provide the key to understanding it.
Dogs were the first domestic animals, emerging 15,000 or 30,000 years ago, long before the invention of farming. According to an earlier theory of dog domestication, our ancestors snatched wolf pups from the den, tamed them, and carefully bred a new species to serve as companions, sentinels, and hunting partners. The first stage, adopting pups, surely happened, given what we know about pet keeping. But the second stage, transforming these captured pups into dogs, poses problems.
Modern experiments show that wolves hand-raised from the age of eight days become relatively tame but are most certainly not dogs: they bite their handlers, cannot be trained to sit or stay, and try to run off as soon as they reach sexual maturity.

More likely, wolves entered the school of domestication not as pets but as scavengers. Wolves trailed bands of
hunter-gatherers, devouring the remnants of the hunt. When people settled into permanent villages, they produced even more materials for wolves: not only animal scraps but also burnt food, rotten fruits, and spoiled grains and nuts.
A genetic mutation that allowed wolves to better digest starch may have played a role in their domestication.
Some of the waste would have been cooked grains and meat, which offered further advantages: the process of cooking renders more of the calories in food available, offering animals who could exploit this resource a particularly rich source of energy. Accessing this food posed risks, because humans tend to be hostile to large wild animals wandering among them. Biologists judge an animal’s wariness in terms of “flight distance”—how far an animal will run away if a human approaches. Flight distance is, in part, genetically determined, and variation exists within populations. Those wolves with shorter flight distances—that is, with a greater tolerance for proximity to humans—claimed more food and reproduced more successfully.

Boars likely underwent a similar domestication process. Wild boars, unlike wolves, did not need to await a genetic mutation to be able to feed on cereal grains: they had always enjoyed the ability to eat starches, along with just about any other substance humans ate. Like dogs, they would have been attracted to the new source of food found in human garbage heaps. Also like dogs, they would have had to undergo an evolutionary adaptation—becoming less fearful of humans—in order to exploit it.

The selective forces of this new ecological niche favored individuals that were bold (not prone to flee at the sight of humans) but not aggressive (because humans would kill those that posed a threat).
The wild animals began to separate into two populations: one tolerated human presence; the other did not.
The boars and wolves most adept at exploiting this food source bred themselves into the new, human-compatible species that we now know as pigs and dogs.

With dogs, this theory of domestication is largely speculative, based on what we know of dog and wolf behavior. With pigs, however, we can test the theory against archaeological evidence. Ancient dog bones are not uncommon, but their numbers pale in comparison to those of pigs. For every dog Neolithic people kept as a sentry, hunting companion, or pet, they kept dozens of pigs as a food source. People ate pork in quantity and tossed the bones into piles, where they remained buried for millennia, awaiting analysis.

The earliest evidence of pig domestication comes from Hallan Cemi, the site now buried under a lake in Turkey. There, villagers ate mostly young male pigs, and pig bones became more common even as the forest dwindled, suggesting the pigs lived as scavengers within the village rather than as wild beasts roaming the nearby woods. All of the pigs at Hallan Cemi, however, were wild boars: their bones show none of the morphological changes, such as shorter snouts, that indicate domestication. This may have been a simple matter of time: Hallan Cemi was occupied for just four hundred years, and the domestication process may have been only getting started when the village was abandoned.

A longer run of evidence comes from a site known as Cayönü Tepesi, not far from Hallan Cemi along the Bogazçay River, another tributary of the Tigris. Settlement at Cayönü started slightly later than at Hallan Cemi, around 8500
bc
, and the site was continuously occupied for nearly 2,000 years.
And over that span, the pig bones change from wild to domestic.

Because domestication is an evolutionary process, there is no clear threshold when a group of animals stops being wild. It’s
better to think of the human relationship with such animals as a continuum: it starts with hunting, moves on to various forms of human management of wild populations, and continues to full domestication.
*

Evidence of this process might start with a shift in the demographics of the animals killed—such as the goats in the Zagros or the pigs at Hallan Cemi—and gradually proceed to a change in morphology. This is exactly what we see at Cayönü Tepesi.

Neolithic people drew this image of a wild boar hunt in what is now Turkey in about 7000
bc
, roughly the same time and place that the animals first entered into partnership with people. Pigs domesticated themselves, lingering near human settlements to scavenge food and gradually evolving into domestic creatures. (Courtesy Omar Hoftun, Creative Commons Attribution–Share Alike)

As time progressed at Cayönü, the village’s residents killed pigs at progressively younger ages, suggesting human control similar to that at Hallan Cemi. Hundreds of years later,
evidence began to appear in the structure of the bones as well. Compared to their wild ancestors, domestic pigs have shorter snouts, smaller brains, and more crowded teeth. These changes are most likely a side effect of domestication. Domestic animals are selected for docility, which is a juvenile trait—young pigs are less aggressive than adults—and the genes for docility come packaged with other juvenile traits, such as a shorter snout and smaller teeth. Just as domestic pigs preserve their juvenile docility into adulthood, they hold on to a more juvenile skull shape too. Scientists know that when they find adult facial bones of a certain shape, they are looking at a domestic pig.

The changing shapes of the bones at Cayönü Tepesi indicate a gradual process of domestication. The archaeological record reveals that, over the 2,000-year period of settlement at the site, wild boars lived among people, gradually evolving into domestic pigs.

The same continuum from wild to domestic characterizes the archaeological record of other domestic animals, but it’s worth noting a crucial difference. Goats and sheep became domestic through their role as prey for human hunters: people first killed wild animals, then managed wild herds, and finally managed domestic herds. Pigs became domestic through their relationship not with humans as hunters but rather with humans as villagers. People tracked down goats, but pigs tracked down people. Once domesticated, goats retained their original habitat, the scrubby hills and grassland outside town, whereas pigs took up residence right alongside humans. From the start, it was a more intimate relationship, involving everyone who lived in town rather than just herders assigned to the task.

Pigs, moreover, had a job to do beyond providing meat. They cleaned up the waste that accumulated in each village they occupied: dead animals, rotten food, and human feces. The
villagers could not have understood that this was a useful public health measure, but they would have been happy to be rid of the stink.

Pigs possessed alchemical powers, transforming garbage into food. At first, this must have seemed like a godsend. In time, however, people came to despise the pig for doing precisely the job it had evolved to do.

*
As America’s feral swine problem indicates, this process also works in reverse.

THREE

“The Pig Is Impure”

B
uilt in about 2550
bc
, the Great Pyramid of Giza stands 455 feet tall and comprises some 2.3 million blocks of stone weighing about 13 billion pounds in aggregate. Archaeologists still argue over whether those stones were moved into place using levers, sledges, or oil-slicked ramps.
Whatever the technical method, building the pyramids involved a feat of social engineering just as impressive as the mechanical: Egyptian authorities had to feed a workforce of thousands of people for decades at a time.

The builders of the Great Pyramid called upon the resources of the entire Nile Valley to support this effort. The royal house sent orders to the heads of villages, who in turn sent men to the Giza site, along with grain and livestock to feed them. Workers drank beer, a muddy beverage fermented from grain and consumed more for nutrition than for pleasure. They ate heavy loaves of wheat and barley, supplemented with beef,
mutton, and goat. One archaeologist analyzed some 300,000 bones at the pyramid complex and found that nearly all the animals eaten were young and male.
This proved that Giza was a provisioned site, with animals raised elsewhere and the juvenile males—not needed for breeding—marched to slaughter at the pyramids.

One village that provided livestock was Kom el-Hisn, located in the Nile delta about seventy-five miles downriver from the temple complex.
Villagers at Kom el-Hisn raised cattle but ate very little beef: only the bones of worn-out breeding cows and sick calves have been uncovered there. Instead, the villagers ate pork: for every four cattle bones archaeologists unearthed at Kom el-Hisn, they found one hundred pig bones. It seems that the residents kept herds of pigs that foraged in the Nile delta marshes and scavenged trash on streets. Although Egypt’s rulers demanded cattle from Kom el-Hisn, along with goats and sheep from other settlements, the villagers’ pigs were spared.

The reasons for this had to do with climate and biology. Animals destined for Giza had to walk hundreds of miles through an arid landscape, feeding on grass and leaves along the way. Well suited for such a journey, cows, goats, and sheep were herded to Giza by the thousands. Pigs, however, would not have found the food or shade they needed along the way. The state couldn’t move pigs around, so it ignored them.

This pattern appeared throughout the Near East: officials developed complex food-provisioning systems that depended on the long-distance movement of cows, sheep, and goats. Pigs didn’t fit into such schemes. But despite—or perhaps because of—their lack of usefulness to bureaucrats, pigs didn’t disappear. Instead, they stuck to their original role as scavengers. People on the fringes of society with little or no access to state-supplied food embraced them as a source of meat. Priests and
bureaucrats, who dined on lamb and beef, came to despise pigs. Only the poor ate pork.

F
or its first 4,000 years, agriculture remained a modest affair. The farmers of the Near East lived in mud-brick huts in villages ranging in size from a few dozen to a few thousand people—places like Kom el-Hisn, Cayönü Tepesi, and Hallan Cemi, which did not change much from one century to the next.

The pace of change picked up about 5500
bc
. That’s when people in Mesopotamia—the lands around the Tigris and Euphrates Rivers in present-day Syria and Iraq—developed irrigation agriculture. A thousand years after that, the plow appeared. The first true cities, with tens of thousands of residents and complex social organizations, appeared about 3500
bc
. The Mesopotamians invented writing—first pictographs and later the more abstract cuneiform—and built the first monumental temples, called ziggurats, to worship their gods. Across the Red Sea, Egypt got a slightly later start but achieved more lasting success. By about 3000
bc
, Egyptian rulers had unified a ribbon of land stretching for six hundred miles along the Nile. Scribes created a hieroglyphic writing system about this same time, and laborers were put to work on pyramids.

Culture depends on agriculture, and in Egypt and Mesopotamia the two flourished together. Both empires emerged from desert landscapes along rivers. No one had settled these areas earlier because there wasn’t enough rain for farming, but irrigation allowed farmers to exploit the rich soil deposited by seasonal floods. That soil produced crops in great abundance, which meant some members of society could give up agricultural work and devote themselves to making crafts (pottery, baskets, bricks, tools, weapons), building temples, keeping
records, fighting battles, and serving the gods.
“A human being is primarily a bag for putting food into,” George Orwell once wrote. “The other functions and faculties may be more godlike, but in point of time they come afterwards.” Only when farmers grew enough food to fill the bellies of bureaucrats, priests, and soldiers could these elites go about the business of creating what we call civilization.

Mesopotamia and Egypt built centralized economies and strictly controlled the distribution of grains, dairy products, and meat to the population. The city of Puzrish-Dagan, for example, served as an administrative center for Mesopotamia’s Third Dynasty of Ur, which lasted from 2112 to 2004
bc
. Surviving records show that the ruling dynasty requisitioned tens of thousands of animals from outlying areas. One archeologist tabulated the records from this economic center, tracing the flow of more than 10,000 animals that arrived from the provinces and were then distributed throughout the urban center. The temple claimed lambs and kids, and soldiers ate cattle and older sheep.
The records make no mention of pigs. As in Egypt, they existed but held no interest to the state.

Villagers in both Mesopotamia and Egypt kept pigs purely on their own initiative. Throughout the Near East, pigs could be found wherever there was water. Towns near natural pig habitats—along the Jordan River, for instance—kept the most pigs because the animals could supplement urban scavenging with foraging in the woods and marshes. Towns in drier areas kept fewer pigs. Nomadic pastoralists, on the move for much of the year, kept none. Archaeologists have plotted on maps the areas that received enough rainfall to allow farming without irrigation. All villages within those areas showed evidence of pig remains.
In other words, if it was biologically possible to raise pigs, people raised pigs.

There were variations within this broad pattern. At Tell Halif, a small site on the edge of the Negev desert in what is now southern Israel, the archaeological record shows dramatic swings in the reliance on pork: pigs account for more than 20 percent of animal bones in garbage heaps dating to 3000
bc
. That figure plunges to less than 5 percent five hundred years later, rises again to 20 percent by 1500
bc
, and finally drops once more to less than 5 percent by 1000
bc
. Changes in rainfall levels cannot explain those swings. It seems that the true reason was political: periods of highest pig use correspond with times of weakest state control. Halif was located along a major trade route; when the political situation was stable, the town likely became integrated within a regional economy, and a steady supply of sheep and goats flowed through. When the ruling dynasties descended into chaos—as they did rather frequently—the town had to fend for itself.
That’s when the villagers turned to pigs.

The rise of strong states discouraged pig raising in another way as well: by changing the landscape. As populations grew, they put increased pressure on the land. Farmers felled oaks to make way for olive groves and drained marshes to plant crops. The land, often poorly managed, deteriorated from forest to cropland to pastureland to desert, with each successive stage providing less habitat for pigs. By the time desert scrub prevailed, only sheep and goats could survive.
As pigs lost habitat, they likely began to raid crops in the field, threatening the food supply and thereby earning a spot on the state’s hit list.

Pigs didn’t fit into the new political and agricultural order. As time marched on, they began to disappear. At many archaeological sites, pig bones remain common up through about 2000
bc
, then dwindle away.
A thousand years later, few people raised pigs in any quantity.

In a few spots, however, pigs persisted. They remained important for sites like Tell Halif that were on the margins of empire, far from the urban centers. And pigs became crucial to the marginal people living within those urban centers. Careful sifting of debris from streets has turned up shed milk teeth—baby teeth—of piglets, evidence that pigs were living and breeding among the homes of the world’s first great cities. But not everyone in those cities partook in equal measures.
Archaeologists tend to find pig bones in the areas of cities where the common people lived. In elite areas, they find more cattle and sheep bones.

Some of the most compelling evidence of this pattern comes from the temple complex at Giza. At the official barracks, temple laborers ate provisioned beef driven there from far-flung villages. Nearby, however, another settlement grew up. This neighborhood, haphazardly constructed, most likely housed those who provided services to temple workers and bureaucrats—grinding wheat, baking bread, brewing beer. These people were not part of the official workforce and therefore did not receive food directly from the rulers. Instead they hunted, foraged, and traded for their food, or they raised it themselves. And what they raised was pigs.
Although absent from the residences of official workers, pigs are common in this self-supporting area. Pork offered these common people what we would call food security: a source of meat under their own control.

P
oor people ate pork because it was the only meat they had. The elite refrained from eating it because they had access to other sources of meat. In time, though, the ruling classes began to actively avoid pork.
The Greek historian Herodotus, in the fifth century
bc
,
reported that an upper-class Egyptian man, after accidentally brushing against a pig, rushed into the Nile fully clothed to cleanse himself.

By the start of the Iron Age, about 1200
bc
, elites in the Near East had begun to see pigs as polluting, a view that arose in part from the habits of urban pigs. Though cities had grown large, sanitation systems had not kept pace.
Residents threw garbage into the streets or piled it in heaps outside their doors. This waste included spoiled food, dead animals, and human excrement. Information about ancient sewage disposal is scant; one of the few references is found in Jewish scripture.
“You shall have a stick,” Moses tells his people in Deuteronomy, “and when you sit down outside, you shall dig a hole with it, and turn back and cover up your excrement. Because the Lord your God walks in the midst of your camp, . . . therefore your camp must be holy, that he may not see anything indecent among you, and turn away from you.”

Evidence suggests that the Lord God saw quite a few indecencies among the Israelites and their neighbors. Sewer systems didn’t exist.
A few elite homes and temples had pit latrines, but mostly people practiced what today is known as open defecation: they relieved themselves in fields or streets, and they didn’t bring a stick. This is where pigs enter the picture.

Pigs eat shit.
In many villages around the world today, pigs linger around peoples’ usual defecation spots awaiting a meal.
Some English pigs in the eighteenth and nineteenth centuries had the same habit. In China, archaeologists discovered a terra cotta sculpture, dating to about 200
ad
, showing a pig in a sty, with a round, roofed building just above it.
The structure was originally identified as a grain silo for storing pig feed, but the model in fact depicted a combination pigsty-outhouse: people sat on an elevated perch and made deposits to the hungry pig
below.
The practice was widespread—the same Chinese character designates both “pigsty” and “outhouse”—and has survived into the present on Korea’s Cheju Island.
In the 1960s more than 90 percent of farmers on the island used a pigsty-privy in their subsistence-farming regimen, and they insisted the arrangement produced the sweetest pork in the world.

This Chinese sculpture, dating to about 200
ad
, depicts an outhouse perched over a pigsty. All over the world pigs ate human waste, carrion, and rotting garbage, a habit that made them quite useful—they cleaned the streets and transformed filth into meat—but sometimes turned them into pariahs. (Courtesy John Hill, Creative Commons Attribution–Share Alike)

The pigsty-privy apparently did not exist in the ancient Near East, but pigs discovered this food source on their own. Tapeworm eggs have been found in fossilized pig feces from ancient Egypt.
Since these eggs are produced only by adult tapeworms living in human guts, it appears that human feces formed part of Egyptian pigs’ rations.
In Aristophanes’ play
Peace
,
dating to the fifth century
bc
, a character notes that a “pig or a dog will . . . pounce upon our excrement.”

This particular dining habit did not improve the pig’s reputation. Just as troubling was the pig’s taste for carrion, including human corpses when available.
Eating human flesh and eating excrement are nearly universal human taboos, and eating animals that eat those substances carried a transitive taint.
“The pig is impure,” a Babylonian text asserted, because it “makes the streets stink . . . [and] besmirches the houses.” An Assyrian text from the 670s
bc
contains these curses:
“May dogs and swine eat your flesh,” and “May dogs and swine drag your corpses to and fro on the squares of Ashur.”

Dogs and pigs had first domesticated themselves by scavenging human waste, but now that role made them pariahs. Filthy animals offended the gods and therefore were excluded from holy places.
The people of the Near East practiced many different religions, but all agreed that the key sacrificial animals were sheep, goats, and cattle and that pigs were unclean.
In Mesopotamia and Egypt, pigs never appear in religious art. The Harris Papyrus, which describes religious offerings made by King Ramses III, includes a detailed list of every desirable item to be found in Egypt and the lands it had conquered, including plants, fruits, spices, minerals, and meat.
Pork does not appear on the list.
“The pig is not fit for a temple,” a Babylonian text reads, because it is “an offense to all the gods.” A Hittite text declares, “Neither pig nor dog is ever to cross the threshold” of a temple.
If anyone served the gods from a dish contaminated by pigs or dogs, “to that one will the gods give excrement and urine to eat and drink.”

Many people, for many different reasons, rejected pork in the ancient Near East. Largely arid, it was a land of sheep, goats, and cattle. Nomads didn’t keep pigs because they couldn’t
herd them through the desert. Villages in very dry areas didn’t keep pigs because the animals needed a reliable source of water. Priests, rulers, and bureaucrats didn’t eat pork because they had access to sheep and goats from the state-focused central distributing system and considered pigs filthy. Pigs remained important in only one place: nonelite areas of cities, where they ate waste and served as a subsistence food supply for people living on the margins.

This was the situation in the Near East around 1200
bc
, when a tribe of people known as the Israelites settled in Canaan, west of the Jordan River in Palestine. Like most of their neighbors, the Israelites rejected pork. Unlike those neighbors, the Israelites came to consider pork avoidance a central element of their identity.