FIGURE 2.

Conceptual model showing the predictions of Janzen's (1967) climate variability hypothesis (CVH). (a) Generalised pattern in annual air temperature variability at tropical and temperate locations at low‐elevation (solid lines) and high‐elevation (dotted lines) sites proposed by the CVH. (b) Pattern in organisms' responses intraspecific genetic structuring (dashed darker line and y‐axis on left), thermal breath (T _br), elevational range and dispersal potential (grey solid line and y‐axis on right) predicted by the CVH as a result of latitude, or annual temperature range. (c) A prediction by the CVH for organisms active year‐round without significant seasonal acclimation or shift in thermal tolerance of organisms' thermal performance curves from low and high elevations at temperate and tropic locations.