This clip reproduced with added text-to-speech voice:
“”Dogs wag their tails to the right when they see something they want to approach, and to the left when confronted with something they want to back away from, say researchers in Italy. The finding provides another example of how the right and left halves of the brain do different jobs in controlling emotions.
Unfortunately, because dogs move about so much, the bias can only be detected using video analysis. It's not obvious enough for you to tell whether the next dog you encounter is going to lick your face or turn tail……..””
More at Nature.com’s 'Here boy' makes dogs wag to the right .