Fig. 1. Experimental design: generating parthenogenetic eggs. Oocytes in metaphase of the second meiotic division (A) were activated to obtain: parthenogenetic haploid eggs (1n, B); parthenogenetic diploid eggs, by treating activated eggs with cytochalasin D to prevent extrusion of the second polar body (2n CD, D); parthenogenetic diploid eggs in which the extruded second polar body (F) was subsequently electrofused back to the egg (2n PB, G). The DIC images show these three types of parthenogenetic eggs after their generation. pb, polar body; fp, female pronucleus. The merged fluorescent and DIC images (C,E,H) show 2-cell stage embryos that developed from these activated eggs in which each blastomere was labelled with a different coloured dye. Scale bar: 25 µm.