Even though we think we know everything about dogs, they always find a way to surprise us. They’re much smarter than we give them credit.

After all, dogs have been living with humans for so long that it was only a matter of time before they picked up on our behavior. They can mimic our voices, express emotion, and make financial transactions in exchange for treats.

Negro, a black Labrador in Colombia, “pays” for cookies with leaves from a tree.

At the Diversified Technical Education Institute Monterrey Casanare, Negro is both the guardian dog watching over the students and a campus mascot.

The black dog, Negro, has no owner but he is well-cared for by the school’s faculty and students. He’s given food, shelter, and plenty of scratches and belly rubs. However, over the years as he watched students go to the campus store and pay for their own food –

while they would also give him some of theirs to eat – he decided to take matters into his own paws.

The clever canine snagged a leaf from a tree and with a wagging tail, he brought it to the store’s counter. It was clear to the employees that Negro wanted to purchase some cookies with his newfound currency. It looks like this dog learned a new trick from his human classmates.

The store attendant was charmed by his adorable intelligence and decided to accept his payment.

“He comes for cookies every day,” said store attendant Gladys Barreto. “He always pays with a leaf. It is his daily purchase.” Negro evidently doesn’t understand the saying, “Money doesn’t grow on trees,” but thankfully, the store employees make sure to keep him in check.

Negroes only consume a limited number of cookies to prevent them from becoming overweight.

They can’t simply allow him to strip every tree bare and buy an innumerable amount of cookies. Negro is just one prime example of dog who displays a shocking level of cleverness. It seems that it isn’t solely the students who are learning new information, judging by the vast education colleges provide nowadays.

The video below is bound to tug at your heartstrings if you’re an animal lover, particularly of dogs.