 In the Alveolata group, the remarkable species "Paramecium tetraurelia" underwent three successive rounds of whole-genome duplication and established itself as a major model for paleopolyploid studies.Each "Deinococcus radiodurans" bacterium contains 4-8 copies of its chromosome.Exposure of "D. radiodurans" to X-ray irradiation or desiccation can shatter its genomes into hundred of short random fragments.