Darwinian evolution in the light of genomics Eugene V. Koonin* National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA ABSTRACT Comparative genomics and systems biology offer unprecedented opportunities for testing central tenets of evolutionary biology formulated by Darwin in the Origin of Species in 1859 and expanded in the Modern Synthesis 100 years later. Evolutionary-genomic studies show that natural selection is only one of the forces that shape genome evolution and is not quantitatively dominant, whereas non-adaptive processes are much more prominent than previously suspected. Major contributions of horizontal gene transfer and diverse...