The lowest and highest elevations known for each species are used to delineate its elevational limits. We assume that species potentially exist between their elevational limits. For species that have a single elevational distribution record (resulting in an elevational range of zero) as well as those with elevational ranges less than 200 m, we adjusted their elevation ranges to 200 m. We verified all data for accuracy by experts within the region and any dubious outlying records were removed. Elevational limits were given for 1,488 species, including 314 mammals, 1027 birds, and 147 amphibians in the Himalayas.

For quantifying the elevational range of mammals, birds, and amphibians, we compiled a comprehensive dataset from publications, online academic databases, and field surveys in the Himalayas (see Appendix S1 for the complete data sources). Most of the existing data in the China Himalayas were recorded by the Qinghai-Tibet Plateau scientific expedition organized by the Chinese Academy of Science in the 1960s. To update and verify these data, we conducted systematic field surveys within each subregion of the China Himalayas from 2011 to 2018 and collected species distribution data from regions where data are relatively sparse. These surveys are under the framework of the Second National Survey on Terrestrial Wildlife Resources in China and currently represent the most comprehensive survey of terrestrial vertebrates in the China Himalayas. Details on the field sampling procedures are described in Appendix S2.

The lowest and highest elevations known for each species are used to delineate its elevational limits. We assume that species potentially exist between their elevational limits. For species that have a single elevational distribution record (resulting in an elevational range of zero) as well as those with elevational ranges less than 200 m, we adjusted their elevation ranges to 200 m. We verified all data for accuracy by experts within the region and any dubious outlying records were removed. Elevational limits were given for 1,488 species, including 314 mammals and 147 amphibians. Taxonomy of mammals, birds, and amphibians follows the International Union for Conservation of Nature Red List of Threatened Species Version 2018-2 (http://www.iucnredlist.org), the Handbook of the Birds of the World (BirdLife International Digital Checklist of the Birds of the World Version 2, http://datazone.birdlife.org/species/taxonomy) and the Amphibian Species of the World: An Online Reference version 6 (http://research.amnh.org/herpetology/amphibia/index.html) respectively.