I've noticed that Mongolian flies are smarter than American flies. It seems odd, but I am convinced that it is true. When an American fly meets a window it thwacks against the window repeatedly in an effort to get out. An American fly will stick close to the glass, so that if half the window is open (but the halves are separated by the window frame) the fly will never make it out.
A Mongolian fly, in contrast, takes a different approach to the whole window thing. when a Mongolian fly runs into a window it doesn't buzz in place. Instead it lands, and sits there for a few seconds. Then, the fly makes a wide arc, and lands either on a different window or in a different place on the same one. In this manner a Mongolian fly eventually succeeds in going out of the open half of a half open window.
I have observed this several times. I probably only mentioned it because Douglas Addams talked about a man who invented a fly that could go through the open half of a half open window in one of his books.

I think now that I have observed this difference between American and Mongolian flies I shall apply for a multi-million dollar research grant to study them. The future of the planet is at stake, trust me!