An increase in K-entropy of soil and landscape during time confirms the hypothesis of soil divergence evolution, whereby differences in initial conditions or local perturbations, and dynamic instability appear to have produced more variable soils and landscapes in the study area.
Bond et al. [36] outlined three patterns of genitalic/molecular divergence evolution, the first one being a pattern comparable to what we see in M. coreyi in which the species' morphology has sorted ahead of the "neutral" molecular marker.
So, deriving the abundance of HGT among free-living prokaryotes from their apparent genome size constraint and underlying duplication-divergence evolution is not a circular argument.
In particular, duplication-divergence evolution directly restricts, by construction, the emerging structure of conserved biomolecular networks to scale-free topologies, irrespective of any biological function [ 28].
In particular, we would like to stress that the abundance of HGT cannot in itself restrain the size of prokaryote genomes (nor does it imply duplication-divergence evolution of their genomes).
Alternatively, it would also be interesting to test, on theoretical grounds, whether the interplay between genome size constraints and gene duplication-divergence evolution could account for other seemingly unrelated features of free-living prokaryotes.
In particular, the opposite effects of gene duplication-divergence evolution and genome size constraint, leading to widespread horizontal gene transfers, are unlikely to apply uniformly over the whole collection of prokaryote genes, which perform a wide range of distinct cellular functions.
We propose that the abundance of horizontal gene transfers in free-living prokaryotes is a simple but necessary consequence of two opposite effects: i) their apparent genome size constraint compared to typical eukaryote genomes and ii) their underlying genome expansion dynamics through gene duplication-divergence evolution, as demonstrated by the presence of many tandem and block repeated genes.
This is an interesting Hypothesis paper that interprets the pervasive horizontal gene transfer (HGT) in prokaryotes as a "simple but necessary consequence" of their apparent genome size constraints and the "underlying expansion dynamics of their genome through gene duplication-divergence evolution".
Yet, our main intent in this "hypothesis" paper is precisely to put the emphasis on the premises of the argument (i.e. genome size constraints and duplication-divergence evolution) rather than on a specific mathematical model illustrating the resulting need for widespread HGT.
Again, our main intent in this "hypothesis" paper is to put the emphasis on the premises of the argument (i.e. genome size constraints and duplication-divergence evolution) rather than on a specific mathematical model illustrating the resulting need for widespread HGT.
