Global pollinator declines and habitat fragmentation highlight the critical need to understand reproduction and gene flow across plant populations.

Castilla et al. use spatial, reproductive, and population genetic data to investigate the effects of tree size, conspecific density, and local kinship on maternal and paternal reproductive success in the understorey tree, Miconia affinis, in central Panama. They found that large trees had lower proportions of viable seeds in their fruits but sired more seeds. On average, trees in more dense neighbourhoods produced more viable seeds per fruit; but in dense neighbourhoods with high local kinship, this positive density effect was offset by increased variability in the proportion of viable seeds per fruit.