Weird tree visualization for genetics

I was reading this interesting article on The Spittoon (the 23andMe blog): How Did the Shar Pei get His Wrinkly Skin

Yes, it is interesting to see genetics about dogs, but what was very interesting was the genetic tree diagram that they posted from Vaysse A, et al. PLoS Genet. (2011) vol. 7 iss. 10 pp. e1002316:

As a way to represent a tree, this is very strange. It's hard to see what the length means (e.g., why are Wolves and Boxers longer?) and what the actual angular separation represents (is the spacing between clusters meaningful? How meaningful?). It is certainly compact and efficient in showing the actual clusters, and the coloring makes it easy to identify all the clusters, but the amount of "hinted" information without explanation makes it more confusing than helpful in my opinion.

Anyway, it was an interesting article.