At higher elevations, the plants find the conditions they need for growth, reproduction and survival. This migratory pattern was confirmed for plant species of all altitudinal belts. Compared with trees and shrubs, upward migration was found to be proceeding more quickly in plants with a shorter life cycle and hence a faster population turnover. Similarly, plant species that are specialised in Alpine habitats are migrating more quickly than generalists. These differences in the pace of migration are gradually leading to modifications in the composition of plant communities and their interaction with the fauna.
Bibliography: Lenoir, J. et al. (2008). A Significant Upward Shift in Plant Species Optimum Elevation during the 20th Century. In "Science" vol. 320. www.sciencemag.org/content/320/5884/1768 (en);
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