Originally posted by Twisterdog
However ... there has to be some original experience that leads them to that, I would think. If a boxer bit Sydney once, then perhaps Sydney remembers that and dislikes dogs that look like the one that bit him.
But Sydney never has had a bad experience with boxers. And it doesn't matter if the boxer has cropped or floppy ears. But you are right that he will sometimes get huffy with some pits that are boxer like. I'm not saying that it is just that he looks at a boxer and says oh there's a boxer and I hate them.

There has to be some visual cue that he recognises ...
That's what I mean though. Dogs of a certain breed are going to have similar visual clues. ie. they look the same. It is not necessarily based on the fact that they act the same.

Also with my grandparent's pug. SO many dogs do not like him, and I believe it's based on looks as many dogs are not exposed to dogs that look like him. In that case I believe it is just a fear of the unknown.