Model forcing framework for testing LDG drivers.

Population dispersal is determined either by geographic distance alone, Δ () or by a combination of geographic distance and physical barriers—such as mountains and rivers—) (M1d). Speciation begins when populations of a species become isolated either: by geographic distances Δ () or by physical barriers (Φ) (M1s). These isolated populations evolve independently through time based on their thermal tolerance (). Diverging populations become distinct after reaching a threshold of differentiation. Species ecology is drawn from environmental suitability based on species’ niche (i) and carrying capacity (ii).