Hairy and quirky, gentle and friendly, llamas are often confused with their cousins, the alpacas. Both are members of a group called camelids, which also includes camels, guanacos and vicunas.

Native to the mountainous region of South America, llamas were first imported to the U.S. in the late 1800s to be shown off as "oddities" in zoos. Today there are more than 158,000 llamas in the U.S. and Canada, according to the South Central Llama Association.

Other than being incredibly cute, here are some other bits of trivia about these captivating critters.

Llamas have been used as pack animals for centuries

Native people of the Andes Mountains have saddled the mostly willing animals to move goods over the area's grueling terrain. Carrying loads of up to 75 pounds, llamas can typically travel as many as 20 miles a day, says National Geographic. Sometimes hundreds of them make up pack trains, efficiently transporting items en masse.

Occasionally, their patience is tested. You've heard "stubborn as a mule"? Alpacas can also have an attitude if they decide they're done for the day. A llama carrying too much of a load may just refuse to move or will lie down on the ground. The irritated animals may also hiss, spit or kick until their load is lightened.

They show displeasure

llama making a face An unhappy llama will stick out its tongue or even spit at another llama. (Photo: Ian Dyball/Shutterstock)

Llamas don't exactly keep their feelings to themselves. According to the Pittsburgh Zoo, when one llama is mad at another llama, it will stick out its tongue to express its irritation. If that doesn't do the trick, spitting is also an option. A llama can spit green, somewhat-digested food an impressive 15 feet or even farther.

They are a little like dogs

While they look like their cousins, the alpacas, llamas are more social and friendly. At least that's what the llama people say. "Llamas are like dogs: they are your friend,” Pam Fink, who keeps 13 pet llamas at her home in Georgia, tells The New York Times. “Alpacas are more like sheep. They’re not going to play with you, not going to be your friend.”

According to Modern Farmer, while alpacas love being part of a herd, llamas are more independent. Llamas are also less skittish than alpacas.

They communicate by humming

Mama llamas often hum to their babies, called crias. It helps them learn to recognize each other. Llamas also hum when they're anxious, tired or just curious.

That's not the only unusual sound they make. When a male is interested in a female, he'll often make a gargling noise, called an orgle. Female llamas also make clicking noises.

They don't whine

Llamas aren't the type to bellyache. "Owners must check them carefully to see if they are hurt or sick, because llamas are so stoic they seldom complain," says The New York Times. If they're healthy, the average llama life span is 15 to 29 years.

They make good guard animals

A llama grazes with sheep in a pasture. A llama grazes with sheep in a pasture. (Photo: syazana nadz/Shutterstock)

Llamas can do a great job protecting herds of small animals, chasing off predators like coyotes, according to Oregon State University. Not only will they protect the smaller creatures, but they may also befriend them, "adopting" a flock of sheep or goats as their own personal herd. Plus they're smart enough to tell the difference between a friendly neighborhood dog and a threatening coyote.

They could help prevent the flu one day

Researchers are working to create a universal flu vaccine that would be effective against every strain of the flu, and llamas are playing a big part of the research. Scientists have created a nasal spray derived from several llama antibodies that target many strains of the flu at once. So far it's only in rodent trials, but this one has potential, researchers say. That would mean that you wouldn't need a new flu shot every year and coverage would be more significant.

Llamas are used as therapy animals

Like Labradors and miniature horses, there's something soothing about llamas. They can be trained as professional comforters, working as therapy animals in hospital, schools and nursing homes.

Mary Jo DiLonardo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.

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