A black dog in Columbia, Negro (“negro” is Spanish for “black”), displays a remarkable intelligence in that he seems to understand the concept of money or currency as a medium of exchange.
About seven years ago in 2013, Negro wandered onto the campus of the Diversified Technical Education Institute (Instituto Educativo Técnico Diversificado) in Monterrey, Casanare, Columbia.
Negro quickly discovered the campus store where students would go during their breaks and purchase food.
Negro watched as the students hand money (in the form of peso banknotes) to the store, then receiving food back.
But the dog didn’t have access to money, so he decided that leaves would be his currency.
As recounted by Angela Garcia Bernal, a teacher at the institute:
“He would go to the store and watch the children give money and receive something in exchange. Then one day, spontaneous, he appeared with a leaf in his mouth, wagging his tail and letting it be known that he wanted a cookie. When you first see it, you almost want to cry. He’s found a way to make himself understood. He’s very intelligent.””
Store attendant Gladys Barreto said:
“He comes for cookies every day. He always pays with a leaf. It is his daily purchase.”
Source: Animal Channel