Simultaneous pulsed flowering in a temperate legume: causes and consequences of multimodality in the shape of floral display schedules

1. In plants, the temporal pattern of floral displays, or display schedules, delimits an individual's mating opportunities. Thus, variation in the shape of display schedules can affect the degree of population synchrony and the strength of phenological assortative mating by flowering onset date. A good understanding of the mechanisms regulating the timing of flowering onset has been developed, but we know less about factors influencing subsequent patterns of floral display. 2. We observed unusual multimodal display schedules in temperate populations of the annual legume Chamaecrista fasciculata. Here we ask if ‘flowering pulses’ are simultaneous among individuals and populations and explore potential underlying mechanisms and consequences of pulsed flowering. 3 .We monitored daily flower production for individual plants from genetically divergent populations during a series of field experiments that manipulated three potential influencers of display schedule shape: average daily tempera...