Table S1 Cell volumes at the 4-cell stage and processed volume calculations. (XLSX) Table S2 (TIF) RT-PCR primer list. Movie S1 Bright field time lapse of normal medaka development. Movie shows a developing medaka embryo between the 4-cell and 256-cell stage with a gap of 25 seconds between images. (AVI) Movie S2 Confocal time lapse of normal medaka development after H2B-eGFP mRNA injection. Movie shows a developing medaka embryo that has divided symmetri- cally to the 4 cell stage. Movie ranges from 4 cells to 1000–2000 cells with a gap of 4.107 minutes between images. The embryo develops a clear metasynchronous cell division. (AVI) References 1. Newport J, Kirschner M (1982) A major developmental transition in early Xenopus embryos: I. characterization and timing of cellular changes at the midblastula stage. Cell 30: 675–86. Available: http://www.ncbi.nlm.nih.gov/ pubmed/6183003. 2. Kane DA, Kimmel CB (1993) The zebrafish midblastula transition. 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