Figure 1.

Experimental design to estimate the fitness cost associated with the csr1-1 and axr2-1 resistances. The artificial cline buildup here has one resistant “source” population and nine “sink” populations with an asymmetric seed migration m_s→x from the source to the sinks. Sink populations receive migrant seeds (m_x+1→x and m_x−1→x) from adjacent populations, and the remaining proportion m_x→x of seeds comes from their own populations (see materials and methods for description of values of migration).