When input changes become frequent, the Pareto front shows complex changes in shape.

<p>We plot the Pareto front changing the parameter , which describes the typical duration between input changes. The archetypes of effectiveness and economy (marked in blue and red, respectively) are connected by the Pareto front (green) , which for any finite is split into two parts. For the Pareto front resembles its limit of rare input changes (a–c). As gets smaller a local Pareto front (cyan) emerges and a separatrix emerges (red-dashed) and grows. When (d) a local minimum (square) and a saddle point (triangle) emerge for the economy task. And when (e) the same occurs to the effectiveness task and the branches of the Pareto front becomes disjoint, until (f) where two parallel lines emerge. Red dashed lines are points where contours are tangent but are not part of the Pareto front (see <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1003163#s4" target="_blank">methods</a>).