Corvids seem incredibly intelligent despite their tiny brains. I do not understand how they can tell one human from another, but they do. A rook makes her prese

Corvids seem incredibly intelligent despite their tiny brains. I do not understand how they can tell one human from another, but they do. A rook makes her presence known to me unobtrusively every morning as I walk into work, and in return I leave some of my scone behind where she will find it. She is then joined by two other birds.