Local adaptation occurs along altitudinal gradient despite the existence of gene flow in the alpine plant species Festuca eskia. (rsos.royalsocietypublishing.org)
Spatial analogues have also been exploited along altitudinal gradients to project vegetation composition, snow conditions for skiing, and avalanche risk (e.g., Beniston and Price, 1992; Holten and Carey, 1992; Gyalistras et al., 1997). (ipcc.ch)
This is a traditional and alternative trail to go to Machu Picchu, which combines several altitudinal levels, with uphill hikes up to 4,600 m. (inkajunglebycar.com)