This dog gives us an excellent look at arousal; in this case, predatory arousal. Note her dilated pupils and wide-mouthed panting. Watch during the first five seconds of the video as she licks her lips — this is a calming signal asking the person with the camera to please “back off.” Keep an eye on her tail position and movement. Do you think she wants to make friends with the squirrel?
There are at least two additional warning/calming signals in this video. Can you spot them? (Hint: Watching with the volume off helps.)