Moreover, the greater genetic tractability of these organisms will greatly aid in establishing how gene modification caused novel forms to appear. The social amoebas provide other opportunities to retrace the evolution of multicellular development. All known species can be grown under laboratory conditions and complete their multicellular life cycle within a 28 hour period. They show a broad range of different morphologies, with terminal structures varying in size between 0.1 mm and several centimeters. The genome of the model species D. discoideum is completely sequenced (10) and sequencing of four other Dictyostelia genomes is in progress.