fighting bullies

Question
I have a 3 year old neutered male and a 1+ year old spayed feamle.  They have gotten along just fine until recently - now they are fighting more and more and it is escalating in intensity.  Can't really identify any particular trigger - sometimes it seems as though one of them looks at the other "oddly" and it's off to the races.  Any suggestions?

Answer
I hear these stories more and more these days. I can't explain why some dogs will get along forever and some suddenly turn on each other. It may be a jealousy thing. It may be a territorial thing.

When you see "the look" act immediately to defuse the situation before the go at it if you can. If there's a toy involved, or a food dish, or even a person, try to figure out what's setting them off.

If you can't solve this, one may have to go.