Main characteristics of the ten sampled localities (ordered from South to North).

Sample sizes (n) and levels of δ 13C and δ 15N (mean + SE) correspond to lizard tail tips for each locality. Shortest distance to the coastline and average altitude were obtained from a GIS of the area, average annual rainfall was estimated from WORLDCLIM Ver. 1.2 (http://www.worldclim.org) and vegetation type was assigned from 1:250000 charts of [77]. Vegetation types: 1, deciduous dry forest; 2, desert scrubs (mostly Cactaceae); 3, halophyte scrubs; 4, fog desert shrub (mostly Cactaceae, but with humidity from the sea and lichens).Main characteristics of the ten sampled localities (ordered from South to North).