Experimental studies of seedling recruitment from contrasting seed distributions

The authors picked up, then redistributed the wind-dispersed seeds of two isolated parents of Tachigalia versicolor, a tropical tree species growing on Barro Colorado Island, Panama. Offspring recruitment was enhanced by the high cohort density at a large spatial scale (within a circle of 100m radius) because of predator satiation. At the same time, it was enhanced slightly by the evenness of the distribution within this scale because of density-dependent mortality at a smaller spatial scale (1m²). Therefore, selection on dispersal by T. versicolor should act to increase the uniformity of the seed distribution, but not to increase dispersal distance to the point that the density of the seed shadow is diluted. -from Authors