Numerous complex mathematical theories have been proposed to explain why annual growth rates of plants scale as the 3/4 power of total body mass, why total leaf mass per plant scales as the square of trunk diameter, and why a host of other widely reported ecological phenomena occur. In this issue, Hammond and Niklas unveil a new computer model, called SERA (for spatially explicit reiterative algorithm), which accurately predicts these and many other scaling relationships as plants are forced to conform mathematically to a few very simple physical principles while they compete for light and space. In each SERA simulation, tree canopies are depicted as thinshelled hemispheres and trunks are modeled as simple, untapered cylinders that increase in girth as simulated plants age. A hypothetical landscape is randomly seeded with a specified number of propagules and monitored during every growing season to assess biomass- and age-dependent allometric relationships. A graphic module allows a population or community to be observed at any stage in its growth as old plants die and new ones propagate. In this image, the observer is standing at ground level and looking up into a forest composed of a single species mathematically modeled to mimic the allometry of a population of Abies alba.