Every animal has a niche to fill in the world, and I think the clowns of the songbird world are the northern mockingbirds (Mimus polyglottos). They have a real knack for imitating sounds including other birds songs and many human and mechanical sounds. They can even mimic short musical verses. When a mockingbird shows up, you never know what noises it may make. You may get a sweet, melodious song, or you may get the neighbors dogs barking or a door slamming. That ability to sound like all sorts of other things is interesting enough, but they are also have brazen personalities and often do some crazy things. They are well known for chasing crows, cowbirds, and birds of prey that come into their territories or get too near their nests. And their aggressions can extend to other animals as well. A pair always nested in the sea grapes that grew behind our dorm in college. They would regularly dive bomb our dogs if we took them out the back door. They would usually wait until the dogs got into position to eliminate, making them less mobile and less able to defend themselves. Mockingbirds are also commonly seen attacking their own images in rear view mirrors or windows. It really is very interesting (and often comical) watching their behaviors.