Passive uplift of plant and animal populations during mountain-building.

If a community and its substrate are raised by tectonic uplift, the species present can either die out in the area, survive in situ unchanged, or survive in situ with adaptation and differentiation. The large-scale passive uplift of plant and animal populations during mountain-building is accepted in a growing number of studies, but the idea has seldom been examined critically. If passive uplift does occur, it has implications for interpreting community structure and speciation in some of the most biodiverse places on Earth, tropical mountains. It would also provide a simple explanation for many altitudinal anomalies, such as the occurrence of typical coastal elements at unusually high altitudes in certain localities. Examples include the coastal saltmarsh plant Salicornia at 4200 m altitude in the rapidly uplifted Andes, coastal frogs and ferns in African mountains, and inland mangroves in New Guinea. The first aim of this paper is to review previous work on passive uplift worldwide and the main ideas that have been discussed. A second goal is to discuss possible tests of passive uplift.