For one, we have twice the number of bacterial species. But it seems more important to me that only 4% of the microbiome is shared between humans and mice.
That second argument does not imply that humans are more confusing than mice, just different.
My reaction was only against the apparently underlying assumption that humans, biologically, are more complex than mice, a remain of the idea that they are more evolved or a biased perspective due to the fact we study them in more detail.
