"Level of genetic organization";"Relevant population";Examples;Conservation;Effects;Refs "Standard genetic code";"Most organic life on earth";"Rules by which four DNA base letters with 43 = 64 possible three-letter words encode 20 standard amino acids (some words are redundant)";"Several deviations in natural microbes";"The nature of the code affects the evolvability of all life on earth";"Maynard Smith and Szathmáry (1995); Ling et al. (2015)" "Basic chromosome structure";Domain;"Multiple linear chromosomes in eukaryotes. One or two circular chromosomes in bacteria.";"All eukaryotes have multiple linear chromosomes, deviating much in number. Most bacteria have one or two circular chromosomes. A few have linear chromosomes.";"Multiple linear chromosomes allow vast expansion of regulatory ability of individual genes and modules, increased genome size, and sexual differentiation. One or a few circular chromosomes allow efficient replication.";"Maynard Smith and Szathmáry (1995)" "Core regulatory gene complexes (“kernels”)";"Kingdom and Phylum";"Genetic networks controlling multicellular and multinuclear organization. Heart-field specification shared by arthropods and vertebrates.";"Highly conserved and invariant. Deviation often leads to developmental catastrophe.";"Determine primary kingdom and phylum-level characters that influence basic organismal structure and interaction with the environment";"Davidson and Erwin (2006)" "Peripheral regulatory genes that affect signal transduction systems";"Class, Order, Family";"Wnt, Hedgehog, Notch in animals";"Flexible deployment, even in related species";"Determine morphological pattern and size of body parts";"Davidson and Erwin (2006)" "Protein-coding genes under regulatory control";"Genus, Species";"Skeletogenic and pigment cell differentiation batteries in animals";"Labile and undergo continuous renovation";"Determine functional capabilities of body parts";"Davidson and Erwin (2006)"