I don't yawn a lot, but I do yawn when I am bored, really tired, or when I notice someone else yawning. I've tested it out, and I learn that when one yawns, others do as well, and it's actually been proven. Even when one thinks about yawning they have that chance of yawning themselves.
To be honest, after reading just a few posts above, I myself yawned during the moment.