This has been a Darwinian red herring for a long time. As with any fairy tales, a cult following has been formed around some mythical characters — in this case, it is the Nested Hierarchy (NH). The Darwinian evolutionists claim that by arranging all the extant and extinct species with their fossils or partial fossils into some organizational system, this is suppose to be evidence that support the common ancestry for the diversity of life.
There is just a couple of problems with this Darwinian contrived myth. The classification methods the Darwinians use is circular i.e., they assume ancestral relationships for comparison and differentiation of similar and unique traits to build a tree. The Darwinists then go back and use the tree as evidence for common ancestry. That is not to say that this mythical system is without flaws, but why debate a system that has no basis on reality.
What actual science demands are that are there any real empirical evidence outside of this fabricated NH tree. Where is that direct lineage that we can trace this common ancestry? For every organism on that tree, what is its immediate progenitor? What were the genetic differences? How many genes are required to change from one ancestral form to the next? What were the selection factors and pressure and for how long?
Darwinists need to separate their fantasy from reality. Without know the details of reality there is no way of affirming or falsifying the tree. e.g. Take these 3 simplified tree scenarios and assume Darwinian descent.
Considering the organisms that we have, I can draw the tree as in scenario A or I can draw the tree as in scenario B & C using the same organisms. The Darwinists might argue that B&C are not as probable as A, but when does a Darwinist worry about probabilities.
The reality is that until the Darwinists can answer all those question above for every detailed linkage in the tree their entire NH is a farce. Until then debating the NH is about as much fun as debating how many fairies can dance on the head of a pin.