FIGURE 1: Microfluidics for tracking individual cell lineages. Fission yeast cells are trapped in comb-like thin micro-channels. Fresh medium is constantly supplied through a thick trench to make the external environment un-changed during measurements. Daughters produced by the trapped cells (= old-pole cells) at the end of the channels are washed away by the medium flow, preventing the cell population in the device from saturation. Automated time-lapse microscopy allows us to simultaneously track a large number of independent old-pole cell lineages until death.