Acytota is a kingdom of life covering satellites, plasmids, transposable elements, viroids and viruses, all outside the conventional tree of life but satisfying most life definitions. This review focuses on some aspects of Acytota, their "genomes" and life styles, the dominance of transposable elements and their evolutionary influence on other life forms in order to vindicate the Acytota as a life kingdom no more polyphyletic than other kingdoms and its members no more parasitic than other life forms.

Department of Plant Developmental Genetics Institute of Biophysics Academy of Sciences of the Czech Republic Brno Czech Republic

Genome Diversity Center Institute of Evolution University of Haifa Mount Carmel Haifa Israel

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