Do our cells take family portraits? Yes. Do they comb their cilia out into gelatinous manes? They do. The photographs go up on cellular walls. When are the shots taken? Whenever there is a flash, a burst of white. When do these opportune moments come? When we open our mouths to gape at the fireworks of an angry supernova, when a dentist illuminates our throat, when we swallow a fat firefly.