December 9 is National Llama Day, and there are many reasons to celebrate these wooly South American herbivores—besides, of course, their unbearable cuteness.

Llamas are members of the camel family, and like their Middle Eastern cousins, they've been used for centuries as transport animals for humans, food, and cargo. (In fact, they were first domesticated about 5000 years ago—!!!—in what's now Peru.) Sure-footed and adept at navigating rocky surfaces, llamas are also deeply in touch with their own boundaries, and if you try to make them carry too much weight, they'll simply lie down until you lighten their load. (Have we made the llama our mascot whenever our iCal is double-booked with meetings? Obviously.)

As llamas are herded from one place to another, they help our planet with their grazing patterns, which help subdue invasive species and clear dead or overgrown brush that might cause wildfires. Grazing llamas also help carry and plant seeds that catch onto their wooly coats as they pass by plants and flowers.

In modern times, llamas have been adopted by American farmers as defense animals. Because they're quite territorial, llamas are surprisingly effective at scaring coyotes, foxes, snakes, and other predators from their barnyards. (They're also not shy about giving a swift kick if an animal gets too close.) And because llamas graze available plants and drink less water than horses or mules, they're seen as both cheaper and better for the planet when it comes to pack animals.

Of course, llamas are currently most famous because they are delightful internet creatures. Proof: