Figure 1.

Conceptual framework of invasion niche dynamics: Schematic representation of different niche dynamic categories within the environmental space showing the distinction between niche expansion and pioneering and between niche unfilling and abandonment, following Atwater et al.²⁴ and Guisan et al.³⁷. Yellow and green circles represent the available climates and red and brown circles represent the occupied climates in case of native and introduced regions respectively. Different niche dynamic categories are indicated by solid colours viz: pink: abandonment (A) – proportion of the native niche not overlapping (non-intersecting) with the invaded niche outside the analogous environments; yellow: pioneering (P) - proportion of the introduced (invaded) niche not overlapping with the native niche outside the analogous environments; blue: unfilling (U): proportion of the native niche not overlapping with the invaded niche within the analogous environments; light green: stability (S) - proportion of the native niche overlapping with the invaded niche within the analogous environments and red: expansion (E) - proportion of the invaded niche not overlapping with the native niche within the analogous environments.