Simulation code for: The role of phenotypic plasticity in the establishment of range margins

It has been argued that adaptive phenotypic plasticity may facilitate
range expansions over spatially and temporally variable environments.
However, plasticity may induce fitness costs. This may hinder the
evolution of plasticity. Earlier modelling studies examined the role of
plasticity during range expansions of populations with fixed genetic
variance. However, genetic variance evolves in natural populations. This
may critically alter model outcomes. We ask: How does the capacity for
plasticity in populations with evolving genetic variance alter range
margins that populations without the capacity for plas- ticity are
expected to attain? We answered this question using computer simulations
and analytical approximations. We found a critical plasticity cost above
which the capacity for plasticity has no impact on the expected range of
the population. Below the critical cost, by contrast, plasticity
facilitates range expansion, extending the range in comparison to that
expected for populations without plasticity. We further found that
populations may evolve plasticity to buffer temporal environmental
fluctuations, but only when the plasticity cost is below the critical
cost. Thus, the cost of plasticity is a key factor involved in range
expansions of populations with the potential to express plastic response
in the adaptive trait. This article is part of the theme
issue ‘Species ranges in the face of changing environments (Part
I)’.