SANTIAGO DE MACHACA, Bolivia (AP) — Stormy winds, frosty nights and a scorching midday sun make life difficult on the Andean plateau, but the docile, tough-natured llama is one reason why indigenous people have been able to survive the harsh conditions for millennia.

With an estimated 3.1 million llamas and alpacas in Bolivia, the South American country counts more of the coarse-haired mammals than any other nation in the world, relying on it to haul goods up steep mountainsides, provide meat, wool and leather.

The llama, which is a relative of the camel, also holds a sacred place in Aymara and Quechua rituals for Pachamama, or Mother Earth. Throughout various regions of the country, herdsmen bury llama fetuses that have not survived birth, hoping to receive rain and good harvests in return. Many local priests also water the earth with llamas’ warm, sacrificial blood.

“You have to give (the gods) an offering,” said herdsman Francisco Tellez, who lives in the town of Curahuara de Carangas and says that he has a special connection with the animal. “The llama understands me. I whistle and he recognizes me.”

But he added: “My son does not like herding; he prefers to be a driver in the city.”

It is a sentiment that speaks to the plodding decline of a traditional way of life in Bolivia’s wetlands, where young people have left behind ancestral customs in favor of taking a chance in the cities.

“Now you just see elders and children herding the animals,” said Carla Rodas, an anthropologist at the Higher University of San Andres in Bolivia’s capital, noting that the llama was once so sacred it was almost considered to be a person.

Friendly and endearing, the llama has wandered across the Bolivian plains in scattered herds since it was domesticated in South America more than 4,000 years ago. The animal, which belongs to a family that includes the guanaco, alpaca and vicuna, has been partly credited with helping the Incan empire expand to parts of modern-day Bolivia, Peru, Ecuador, Colombia, Chile and Argentina until the Spanish arrived in the 16th century.

As they adapted to living in the Andes mountain range at altitudes of up to 5,000 meters (16,400 feet), the animals also became a crutch for locals navigating steep, craggy terrain with loads of goods such as potatoes, salt, dried meat and quinoa.

On a recent morning, shepherd Genaro Arce left at 5 a.m. in sub-freezing temperatures to round up his eight llamas before taking the males and females to different pastures. Roughly 200 other animals and their young impatiently waited to graze.

His wife, Genoveva Usnayo, worried that foxes and stray dogs might attack their animals at night.

Once a year, she and her husband shear the llamas’ wool and sell the threads in markets to make winter clothing.

When she has time, Usnayo spins and weaves her own wear, but says it is nearly impossible to undercut the price of synthetic wool that saturates the market. The laborious, time-consuming process of making traditional clothes involves operating a spinning wheel and stretching fibers.

“It’s hard but you have to face it. Without getting your hands dirty you can’t live. Children do not think like that,” Arce said, noting that his youngest daughter, Maria Arce, is his only child who currently lives at home.

Her older five siblings migrated to cities to try their luck. Only a few decades ago, most Bolivians lived in the countryside. Now 75 percent live in cities.

For now, many elders still manage to eke out an income by relying on agricultural crops and their earnings from wool.

“The llama taught Andean people to adapt themselves to a cold and arid land, and still today, in spite of climatic and economic changes, it allows them to live,” Rodas said.

But Maria Wurzinger, a zoologist at the University of Vienna in Austria who studied camelids in Bolivia and Peru, worries that might not always be the case due to diminishing rainfall.

“There will come a time when there will be no more grass and you will not be able to breed llamas or alpacas,” she said, adding that Bolivia’s wetlands could eventually become a desert.

“With irrigation it is difficult to sustain grazing,” she said. “If climate predictions are right, many will stop breeding animals.”