new hummingbird experience

I sat on the porch watching the hummers -- two of them -- vie for the feeder. The one was flashing his ruby throat at me from tree to tree or even in mid-air. Then they seemed to be playing somewhat of a game in the redbud tree. One would be in the tree on one side and the other bird out from the tree in the air. The air one would fly into the tree on its side and the tree one would come out of the tree on the other. Then the new air one would fly into the tree on its side and the new tree one would fly out. This went on and on for at least 10 exchanges. It was like those things with the steel balls hanging on strings and when you raise one and let it hit the others, the one on the other side pops out and when it hits backs, the other side pops back out. Fascinating!!!