Spatial settings of populations and environmental effects. Fifty-five populations of 500 individuals each were spread homogeneously on a 5×11 grid along 11 latitudinal positions. E(Y) represents the environmental effect at a given latitude Y and is scaled by kE (see equation 8). No selection was introduced: stabilizing selection was canceled with ω2 = 109 and all populations shared a phenotypic optimum Zopt = 0.
Soularue and Kremer BMC Evolutionary Biology 2012 12:79 doi:10.1186/1471-2148-12-79