Discovering South America's Camels
by Mary-Russell Roberson
In 1951, Carl B. Koford of the Museum of Vertebrate Zoology at the University of California, Berkeley, was the first to study a mammal called the vicuña in its high-elevation habitat. Camping at 15,500 feet—three miles above sea level—in the Peruvian Andes, Koford described his first glimpse of vicuñas in a 1957 Ecological Monographs:
High in the central Andes of western South America, above the limit of cultivated crops, lies a treeless pastoral zone, the puna. While scanning the bleak rolling grasslands…a traveler may be startled by a prolonged screech. The cry attracts his gaze to a racing troop of fifty gazelle-like mammals, bright cinnamon in color—vicuñas! …[The animals are fleeing] the approaching llamas and the somber Indian who trudges behind them. …the vicuña is reputed to spend its life at heights reached only by the lofty peaks in his own country, and…it bears a costly fleece which, centuries ago, clothed Inca royalty. To him the vicuña resembles, in size, actions, and habitat, the pronghorn antelope of the Great Plains. But inasmuch as the vicuña has a long neck and rather large feet, and lacks horns, it is more like a small humpless camel.
|A herd of guanacos, one of South America's camel species, in Torres del Paine National Park, Patagonia, Chile. (David Mathies/iStockphoto.com)|
Koford evocatively captured the essence of the vicuña's story: its habitat, size, group-living. Its value to people. Its adaptations—incredibly, it was running in the thin air of that altitude! And its place in the pantheon of mammals. Like its three South American cousins, the wild guanaco and domestic llamas and alpacas, the vicuña is, indeed, a sort of camel.
Camels Move On
What most people think of as camels—dromedaries and Bactrians—are so firmly associated with the deserts of Africa and Asia that it is hard to believe they have close relatives in South America. Camelids originated in North America 40 to 45 million years ago, then evolved on the continent's grasslands into a diverse array of forms, including the gazelle-like Stenomylus, the giraffe-like Aepycamelus, and the nearly 12-foot-tall Titanotylopus, which resembled today's Old World camels. William Franklin, professor emeritus at Iowa State University in Ames, says, "At one time, there were probably several dozen genera of camelids in North America. In some areas, they were surely the dominant large herbivores." Then, six to three million years ago, opportunities for leaving their homeland arose when the Earth's climate cooled and sea levels fell, exposing land bridges to the south between Panama and South America, and to the north across the Bering Strait between Alaska and Asia.
Those that migrated north, from a "tribe" of camels called the Camelini, spread across Eurasia and eventually evolved into several species including the dromedaries and Bactrians we know today. The Lamini tribe went south and evolved into, among others, the vicuñas and guanacos of South America, and most recently their domestic forms, alpacas and llamas.
The camelids remaining in North America persisted until near the end of the Pleistocene epoch between 10,000 and 15,000 years ago, when like so many other large mammals they went extinct due to human overhunting, climate change, introduced diseases, or some combination of these factors. Except for the vicuña (Vicugna vicugna) and guanaco (Lama glama), South American camelids went extinct about the same time. Some Eurasian camel species may have survived a bit longer, but today only domestic dromedaries, domestic Bactrians, and a handful of wild Bactrians (Camelus bactrianus) remain.
Even though the Old World Camelini and New World Lamini diverged about 11 million years ago, many similarities remain. All of the camelids are herbivores living in open habitats from savanna grassland to desert, and their split upper lip helps them grasp and tear off bits of grass or leaves. They also possess long necks, slender heads, long eyelashes, padded feet with two toes, and the ability to get by without much water. They can "kneel" on their hind legs when they sit down, unlike cows and horses.
All camelids also have a three-chambered stomach. Food goes to the first stomach chamber where it is partially digested, then regurgitated—in other words, camelids "chew the cud" just as cows do. The cud is swallowed and moves through the next two chambers to be fully digested. This complex digestive system ekes out as much energy as possible from diets that are mostly grass.
When defending themselves or fighting for dominance, camelids spit the contents of their mouth or a foul-smelling fluid from the first chamber of their stomach. Another behavior all camelids share is their curious walking gait, whereby their legs on each side move in unison rather than alternating, as do those of most other four-legged mammals.
There are differences too, the most obvious being that South American camelids have no humps, and are much smaller than Old World camels. While dromedaries and Bactrians weigh in at 1,000 pounds, the heaviest South American camelid, the domestic llama, weighs only about 185 to 300 pounds.
South American camelids also have adaptations that allow them to thrive at high elevations. Their thick wool coats keep them warm, and their extra-large hearts and lungs keep their bodies well-supplied with oxygen in the thin air. And, although they're tremendously useful to people, New World camelids are not nearly so famous as their Old World counterparts.
The Wild Ones
For all their similarities, vicuñas and guanacos—the wild South American camelids—are a study of contrasts. Vicuñas weigh between 80 and 110 pounds and live on windswept, cold, semi-arid plains called puna between about 10,000 and 16,000 feet. They inhabit the Andes in central Peru, western Bolivia, northwestern Argentina, and northern Chile. Guanacos are larger, between 185 and 300 pounds, and are more widely distributed. They live from sea level to 13,000 feet in a wide variety of open habitat in and around the Andes, from northern Peru all the way to the southern tip of South America. The vast majority of guanacos live in a region called Patagonia in southern Chile and Argentina.
The two species' ranges do not overlap much, but where they do, the animals choose slightly different habitats. Vicuñas are more restricted in their diet, eating primarily grass and some small forbs and lichens, whereas guanacos eat shrubby vegetation as well. Vicuñas must drink water daily, especially during the dry season; guanacos can go for long periods without drinking water.
Franklin has studied South American camelids for 40 years, beginning with a four-year study of vicuñas in the early 1970s, then studied guanacos as well to compare their ecology and social behavior.
|Scientists are uncertain whether alpacas are the domestic descendants of vicuñas or guanacos. (Mehgan Murphy/NZP)|
Franklin found that vicuñas live in family groups composed of a male, several females, and their young. When the young near maturity, the male forces them out of the group. Unless they're defending a territory alone while attempting to attract females, bachelors form all-male herds while females try to join existing family groups. The vicuñas do not migrate seasonally. Instead, family groups live on permanent, year-round territories that the male defends from all intruders. Although some territories are better than others, each contains sufficient forage to support the group all year. The best territories also have a permanent source of water. Habitat with good forage is found in scattered patches between bare ground and other unsuitable habitat.
Seasonally, territories are also used for mating and breeding. A male defends his females from the attentions of other males, and actively prevents his adult females from leaving. Unusual among mammals, a male limits the number of females that live on his territory—the average is three—probably to ensure there is enough food to go around. Over time, the size of the group on a territory is fairly constant. "Females most likely pick males for real estate, not for good looks," Franklin says. "But the male more often than not rejects outside females. There is a relationship between the number of animals in a group and the amount of the forage in that territory. Who knows how the male assesses what is going on?"
Franklin also discovered that vicuña groups actually use two territories—one for daytime foraging, and a smaller one at a slightly higher elevation for nighttime sleeping, which perhaps offers greater safety from predators. Males mark their territories with dung piles that females and young also use. The piles act as fertilizer, and where the dung piles are on steep slopes, the dung falls downhill and produces strips of relatively lush vegetation.
Guanacos' social system differs from that of vicuñas' in being far more variable and flexible, as is their habitat and feeding ecology. Some guanacos live in sedentary family groups on year-round territories. Others have only seasonal breeding territories and migrate when forage is covered in snow or dries up. Group size varies over the year and females move in and out of the group freely; sometimes females form their own all-female groups. Very large mixed herds of both sexes are also seen in migratory populations. Territorial males drive out their young, but not until they are older than vicuñas are when they are expelled. Guanacos appear not to have separate nighttime territories.
In both species, females give birth to a single offspring each year. As with many ungulates, the young can walk just a few minutes after birth. In fact, Franklin notes that if researchers want to tag infant vicuñas, they must do so within the first 15 minutes after their birth—vicuñas older than that can easily outrun a human.
Archeologists have documented vicuñas' and guanacos' path to domestication, which is believed to have originated in the puna ecosystems of Peru, based on changes in the composition of animal remains in sites of long-time human occupation. People first appeared on the puna about 12,000 years ago, and for next several thousand years they preyed heavily on nearly equal numbers of the two camelids and the taruca (Hippocamelus antisensis), a deer about the size of a vicuña that occupied roughly the same range. Over time, people gradually shifted away from hunting deer toward a specialized hunting of camelids, then to controlling early domestics perhaps by corralling them. Then, about 5,500 years ago, people managed to fully domesticate camelids as part of a herding economy. Llamas and alpacas spread from here and may also have been domesticated independently elsewhere in their range.
|Alpacas at the Smithsonian National Zoo's Kids' Farm. (Mehgan Murphy/NZP)|
People hunted camelids for meat for thousands of years—and still do—and this was mostly likely the impetus for their domestication, according to Katherine Moore, a research associate at the University of Pennsylvania Museum of Archaeology and Anthropology in Philadelphia who specializes in the archaeology of domesticated animals, especially llamas and alpacas. She says, "The human need for food has always been greater than the human need for pelts and wool." Much later—perhaps 1,000 or 2,000 years after the initial domestication—secondary uses of the animals would have been exploited, such as wool and transportation. Moore points out that the exploitation of secondary resources from domestic animals often takes quite awhile. Cows, for instance, were domesticated about 10,000 years ago, but weren't milked until about 5,000 years ago.
Llamas were domesticated from guanacos, a long-established fact undisputed by scientists. "Genetically, they are very similar animals," Franklin says. "There are some differences in color and body size and so forth, but it's pretty clear the guanaco was the wild progenitor of the domesticated llama." It is also clear that, apart from their use as food, people bred llamas as pack animals and for their wool.
Alpacas, which are bred exclusively for wool, have a more complex background that has confounded scientists. For many years, the accepted wisdom based largely on morphology was that alpacas were also domesticated from guanacos, although there were dissenters who argued for a vicuña ancestor, a hybrid guanaco-vicuña ancestor, or a hybrid llama-vicuña ancestor.
Recent DNA analyses by Miranda Kadwell of the Institute of Zoology in London and her colleagues, reported in 2001 in the Proceedings of the Royal Society of London B, yielded seemingly contradictory results: Although analysis of some DNA strongly indicates that alpacas are domesticated vicuñas, almost all of the alpacas from which samples were obtained have a substantial amount of llama and/or guanaco DNA. Still, the now-prevailing view is that alpacas originated from vicuñas, and their current mixed genome is the result of more-or-less recent hybridization among domestics.
Whatever the origins of domestic camelids, which were the only mammals the Andean people domesticated except for the guinea pig (Cavia porcellus), the Andeans were skilled breeders. Moore says that there were likely more domesticated forms than the two that exist now. Archaeologists have found evidence of a larger llama-type animal that was probably used in trade caravans, and small and large alpaca-like animals.
About 15 years ago, archaeologists found some 1,000-year-old alpaca and llama "mummies" in southern Peru. The animals had all been killed with a blow to the head, buried under a house, and left there, perhaps in a religious ceremony. Camelid expert Jane Wheeler, who was then a visiting professor at San Marcos University in Lima, examined the fiber of these animals, which was well-preserved thanks to the extremely dry climate. She was surprised to discover that it was much finer than that of current-day alpacas and llamas. "Finer" translates into "softer" when the fiber is spun into yarn.
Modern-day llamas and alpacas have fiber that is in the range of 20 to 40 micrometers in diameter, with alpaca being at the fine end of the range and llama fiber being at the coarse end. The mummified llama fiber was 22.2 micrometers, and the mummified alpaca fiber was 17.9 micrometers. The mummified animals also carried more fiber at a younger age than modern llamas and alpacas.
The mummies predate the rise of the Inca, indicating that pre-Incan people were already managing the breeding of their alpacas and llamas with the goal of producing fine fiber. This knowledge was lost, however, with the collapse of the Inca Empire at the hands of the Spanish conquistadors.
There is also evidence of differential management of llamas and alpacas. Writing in the Journal of Archaeological Science in 2006, Brian Finucane of the University of Oxford in England and his colleagues suggest that pre-Columbian pastoralists raised alpacas (but not llamas) in the high-elevation puna because cold promotes the growth of their prized fleece. In contrast, camelids at lower elevations, probably mostly llamas, were corralled and fed the maize stalks and husks that remained after crops were harvested. This practice, too, was lost and now alpaca and llama are raised together in the puna while sheep and other non-native livestock occupy lower ground.
Llamas and alpacas are inextricably intertwined with the rise and spread of the Inca Empire, which began to grow in the Peruvian Andes about 1200 C.E. The Inca built beautiful and sturdy walls, buildings, and towns of interlocking stone. They built irrigation systems to keep entire valleys green in the arid environment. And they built 14,000 miles of roads that crisscrossed the empire and eventually extended about 3,400 miles, from Ecuador south to central Chile and parts of Argentina.
Llamas and alpacas were with them every step of the way. Llamas carried materials for building roads, temples, and irrigation canals; baskets of gold and silver out of mines; and cargo for trade. These surefooted animals with padded feet transported whatever needed moving in a society that never invented wheels, perhaps because wheels were far less effective in steep rocky terrain than animals adapted to walking on such rough ground.
|A silver llama figurine made by the Aymara people of Bolivia. (221901.000/David Heald/NMAI, Smithsonian)|
Alpacas were prized for their fine and fluffy wool, from which the Inca fashioned tunics, tapestries, twine, rope, and bags. Men wore wool tunics and women wrapped themselves in larger pieces of wool fabric. But clothes were not just for keeping warm in the cold mountain air. Detailed patterns in a variety of colors spelled out the ethnic group and class of the wearer. Leaders exchanged finely woven clothes to keep the peace. The most beautiful articles of wool clothing were used to dress religious figurines that were burned as offerings to the gods.
Moore says, "We know that cloth and stuff made out of cloth has been very important in the Andes over the years as trade and exchange items, and as a way of showing the symbols of the world you belong to, your beliefs, your rank in society. The earliest cloth we have is already studded with messages." Today, people of the Andes continue to produce colorful and intricately patterned ponchos and hats from the wool of alpacas and llamas.
Alpacas and llamas also supported the Inca Empire with meat, leather, fat for food and candles, pelts for blankets, and dung for fuel. Dried llama or alpaca meat was called charqui, a word that later became "jerky" in English. The Inca stored vast quantities of jerky and similarly dried fish and plants along royal highways to fortify traders and soldiers on long journeys through the empire.
Llama and alpaca wool was also used to make knotted records called quipu. The Inca did not develop a system of writing, but they kept track of immense quantities of food, textiles, precious metals, and people by making knots in colored twine. The importance of llamas and alpacas to the Inca culture is further illustrated by the fact that they were frequently depicted in art such as ceremonial bowls, pitchers, tapestries, and figurines made of silver and gold. Some of the art shows llamas being used in ritual sacrifice.
Their importance is also suggested by European accounts of the size of their herds. Cornell University anthropologist John V. Murra wrote, "It is difficult to imagine the size and pan-Andean distribution of herds. In the early decades after the invasion, European observers were stunned by the omnipresence of the beasts… ." Murra goes on to say one European reported that "he had heard of an Indian who is not even a lord just a local personage…who had more than 50,000 head of stock."
The invasion Murra mentions, of course, is that of conquistador Francisco Pizarro and his small army of Spaniards. In 1532 C.E., they captured Atahuallpa, the leader of the Inca, in the city of Cuzco in what is now Peru. Pizarro demanded and received a room full of gold and two rooms full of silver for the release of Atahuallpa, then executed him anyway. The Inca Empire, already weakened from the onslaught of European diseases, crumbled.
After the Fall
The social disarray that followed the European conquest of the Inca Empire led to the loss of old breeds. Herds of domestic camelids were decimated as European sheep, goats, cattle, and pigs replaced them on pastureland, and they nearly disappeared by the end of the 1500s. Wild camelids fared even worse.
Scientists estimate the pre-Columbian population of guanacos at 30 to 35 million and that of vicuñas at perhaps several million. In the centuries following the fall of the Inca Empire, over-hunting in combination with competition for pastureland from introduced livestock greatly reduced the numbers of guanacos and nearly wiped out vicuñas. By the 1960s, only about 10,000 vicuñas remained. Today, the population has rebounded to several hundred thousand. Guanacos number around 0.5 million, but they occupy less than half of their former range.
Populations of guanacos and vicuñas have stabilized and grown in recent years due to some fairly standard methods—setting aside protected areas and enforcing laws against illegal hunting. A more unusual conservation technique has helped boost the numbers of vicuñas: shearing wild animals and releasing them alive. The ability to legally live-shear the animals reduces people's incentive to hunt them for their fleece, and shorn vicuñas have no value to a poacher.
|Wool made from alpaca and llama fiber. (YinYang/iStockphoto.com)|
Vicuñas have one of the finest fibers in the world, at a diameter of 12 micrometers. (The fiber of cashmere goats is 14 to 19 micrometers, and that of shahtoosh from the Tibetan antelope, or chiru, is from nine to 12 micrometers.) "It's hard to exaggerate the silkiness of vicuña fiber," Moore says. "When you rub a tuft in your fingers, you can see it but you can't feel it, it is so fine." It is so sought-after that in 2004 a kilogram (2.2 pounds) could be sold for $566 wholesale. One ounce of certified live-sheared vicuña fiber retails for $250 in the United States.
According to some reports, the Inca (and perhaps others before them) periodically rounded up thousands of vicuñas, at two- to three-year intervals, in massive efforts involving as many as 30,000 people. Some vicuñas were killed immediately for meat and leather, but most were shorn of their precious wool and set free. The time between roundups was dictated by the time it took the vicuñas to regrow their fleece to a length of one to two inches.
In 1995, to promote both conservation and local economic development, the government of Peru began encouraging its citizens to conduct similar vicuña roundups. Villagers on foot herd vicuñas into a net-lined chute that leads to a small corral, where the vicuñas are inspected and sheared. The fiber of sheared vicuñas grows back completely in two or three years. If the vicuñas' fleece is not long enough or they are youngsters then they are let go.
A study done in Peru and published in Conservation Biology in February of 2007 looked at females shorn in the spring, and found no increase in mortality of the females or decrease in number of young they produced compared to unshorn females. But more research must be done to determine if the same can be said of vicuñas shorn in cold weather.
In some places in Peru, vicuñas are living permanently inside large corrals (on the order of 2,500 acres) to facilitate roundups. However, while corralling makes live-shearing easier, some scientists are concerned that it may interfere with natural gene flow between corralled and uncorralled populations, or that being corralled will set the vicuñas on the path to domesticating themselves.
Live-shearing guanacos is not a widespread practice, but some people think it should be. Guanaco fiber is nearly as fine as vicuñas'. In the wild, the animals are threatened by poaching and by competition from sheep, which graze on similar plants. A study published in the Journal of Arid Environments in 2006 demonstrated a successful process for capturing and live-shearing wild guanacos in Patagonia. The authors propose that a live-shearing program—similar to Peru's live-shearing vicuña program—could enhance the conservation of guanacos, because local landowners would be more motivated to help protect the animals if they were able to earn income from live-shearing.
If these programs move forward, and people can legally shear vicuñas and guanacos on a large scale while leaving the animals wild and free, it will represent an ingenious twist in the age-old story of domestication and the newer story of conservation.
—Mary-Russell Roberson is a contributing editor who last wrote about gliding animals in the September/October 2007 issue of ZooGoer.
If you have a comment about Smithsonian Zoogoer magazine, please email it to us.ZooGoer 37(1) 2008. Copyright 2008 Friends of the National Zoo.