I notice from time to time that, rather than their index finger, some people use their middle finger as a pointer. Whenever I see this, I can't help but think "Doesn't that guy know that he is flipping the bird at everyone?". I always wonder how anyone could not realize how this looks. I notice it in old movies and TV programs as well. I tend to assume that the film predates the modern use of "the bird", but really I don't know when the bird came to be.