Cecil, I appreciate your column on yawning. You did not mention the curious fact that sometimes yawning is contageous even over the phone. New theory?

ETA: Link to column: http://www.straightdope.com/columns/read/533/why-are-yawns-contagious

I would also note that we probably all have (I certainly have) seen dogs yawn with clearly and absolutely no aggressive thoughts.

Yes, just today in fact: Marmaduke by Brad Anderson for June 17, 2011 - GoComics
Powers &8^]

A lot of times they yawn when they’re nervous. Same like a little extra panting.