Once in awhile, my dog will bark and growl at things i don't see. He's older and sleeps a lot, so it is unusual for him to be up at night if we aren't, but he was barking and growling several times last night. At one point, i thought i heard something too, but when i looked outside, there was nothing, and the motion lights weren't on. This morning i read that there was a pretty strong earthquake on the west coast last night. i know other times that my dog has acted strange, there were weather events, some far away. just thought it might be interesting to see if anyone else noticed something similar.