Two things on dogs urinating (interesting article link to discuss!)

Dogs Compete with Pee : Discovery News

I would really like to discuss the article associated with the above link. This article seems to really conflict with many of the things that I have learned about the dominance theory and the myth that dogs are "status seeking."

First of all, it labels dogs as animals of a "higher or lower status" mainly because of their tail carriage. From my research, tail carriage could indicat arousal and/or confidence (which obviously depends on the rest of the dog's body posture, so I'm just speaking about tail carriage exclusively). So a dog with a "higher tail carriage" (not talking about huskies or akitas) might be finding themselves looking at something interesting, or they might just not be fearful in that time and place.

I'm confused as well since a dog can so easily have their tail way up on the air one second, and their tail can be neutral the next once their arousal level has gone down. How can a scientist define a dog as a "higher or lower" status dog based on their tails that change?

Also, I'm confused as well since I always thought that, because dog's "social structures" are so fluid, it is not wise to label a dog as "higher or lower" since one dog might care more about if they get a bone first and share their food, while another couldn't care less about if a dog would take their bone away. Since these dogs are not actually in a living setting together (dogs were observed in a dog park or in a lab setup where a dog was walked on leash), how can one dog's so called "status" be compared with another dog's "status?" Overall, this article is very confusing to me!

My second topic is about a female dog urinating on another female dog. I walk the boxer mix alot, but I was told about an interesting situation: their bichon growled at the boxer mix when they were both on a couch, so the boxer mix got off and layed on the floor (and did this on her own). Then, the bichon got off the couch and backed up onto the boxer mix and urinated on her! I'm not sure if she lifted her leg or not, but I've never seen her lift her leg outside, so my guess is that she didn't do that in that situation either. My question is why would a dog do this? The dogs get along well, but the bichon can get kind of sassy (like she tries to get all of the attention and likes to play "keep away" with the boxer mix sometimes). I'm not sure if those qualities can influence it, but I figured I would throw that in there in case.