References

produces an adaptive number of stomata and helps put them in their place. This stomatal module might be widespread, given that SPCH-like genes are present in grasses and other plants. Collectively, the studies by Cartwright et al. and Lampard et al. (3) reveal mechanisms that control plant cell fate specification and division polarization. Questions outstanding include the nature of intercellular cues that polarize PAN1, how PAN1 coordinates polar cell division and cell fate allocation, and how a MAPK cascade that controls many differ-ent plant processes specifically regulates stomatal development. Life on Earth depends in no small part on stomata that control plant evaporative cooling and CO 2 uptake for photosynthesis, thereby influencing global water and carbon cycling. Pangloss pontificated in Voltaire’s Candide that “this is the best of all possible worlds. ” It is fitting that his eponymous protein and the loquacious SPEECHLESS make this planet lush and green