Fig. 3. Progenitor-generating divisions. (A) A progenitor-generating lineage. The nucleus of the mother cell (white dashed outline) migrates apically (white broken line) and divides to produce two daughter progenitors (red and green dashed outlines). These cells divide again, producing four progenitor cells (yellow, orange, blue and purple dashed outlines) that each divide once more. MIP through 30 z-sections imaged at 1.5 µm intervals; scale bar: 10 µm. (A') Lineage tree for A. (See Movie 3 in the supplementary material.)