Mantid Territory

I was in my kitchen thinking about a feature article I read in National Geographic Magazine last month on Mantids.  Then I noticed these two mantids in my window.  The one on the lower right has been in this window for about two days now.  He noticed the one on the upper part of the window and started walking towards it.  I wasn't sure what to expect next.  Maybe there would be a boxing match.  Then just after I snapped this photo, the one on the top flew over and bit the butt of the one on the lower right before flying off to another window in the room.  It appears that mantids are territorial.