Fig. 5

Ecological niche model projection maps. Predicted range of Rafinesquina alternata (e, 0.5×) illustrating high niche stability during the pre-invasion interval, a predicted range for the C3-2 time slice based on C3-2 niche model, b predicted range for the C3-3 time slice based on the C3-2 niche model, c predicted range during the C3-3 time slice based on the C3-3 niche model, d calculated overlap between b and c, a measure of niche stability. If a species occupied exactly the same niche in two time slices, these range maps would completely overlap. The 88 % overlap indicates strong niche conservatism. Predicted range of Lepidocyclas perlamellosus (j, 0.75×) illustrating low niche stability during the post-invasion interval, g predicted range for the C5-2 time slice based on C5-2 niche model, g predicted range for the C5-3 time slice based on the C5-2 niche model, h predicted range during the C5-3 time slice based on the C5-3 niche model, i calculated overlap between g and h. The 54 % overlap indicates substantial niche evolution. For a–c and f–h, light colors indicate low predicted probability of occurrence while dark colors indicate high predicted probability of occurrence. In d and i, light colors indicate low agreement between original and forward model projections while dark colors indicate high agreement. Modified from Malizia and Stigall (2010)