Mean reproductive investment of mature colonies from the range origin (bottom) to the top edge. Gray lines show standard deviations, dashed line shows starting average of 0.847. Populations in the saturated range interior evolve greater investment in parasitic queens, while those at the uninhabited range edge retain greater investment in dispersing claustral queens.

  Part of: Helms IV JA, Bridge ES (2017) Range expansion drives the evolution of alternate reproductive strategies in invasive fire ants. NeoBiota 33: 67-82.