  Research in quantitative evolutionary genomics and systems biology led to the
discovery of several universal regularities connecting genomic and molecular
phenomic variables. These universals include the log-normal distribution of the
evolutionary rates of orthologous genes; the power law-like distributions of
paralogous family size and node degree in various biological networks; the
negative correlation between a gene's sequence evolution rate and expression
level; and differential scaling of functional classes of genes with genome
size. The universals of genome evolution can be accounted for by simple
mathematical models similar to those used in statistical physics, such as the
birth-death-innovation model. These models do not explicitly incorporate
selection, therefore the observed universal regularities do not appear to be
shaped by selection but rather are emergent properties of gene ensembles.
Although a complete physical theory of evolutionary biology is inconceivable,
the universals of genome evolution might qualify as 'laws of evolutionary
genomics' in the same sense 'law' is understood in modern physics.
