Taxonomies are fractal with, at any node, some number of branches (typically one or two major branches and several minor ones). Here's a fascinating article by Benoit Mandelbrot from 1955 on models of taxonomic structures. Great stuff. The article was published in Information Theory--3rd London Symposium, ed. Colin Cherry, and is hard to find online. At least it was until now.
Only the even pages were copied.
No, all the pages are there.
I wonder if Willis distributions apply to phylogenies, that is, the estimate of the true evolutionary tree. Not an artificial taxonomy. Subjective taxonomies are out of vogue in the field of systematics now. Most effort goes into estimating phylogenies.