The mid-latitude biodiversity ridge in terrestrial cave fauna

Authors

  • David C. Culver,

  • Louis Deharveng,

  • Anne Bedos,

  • Julian J. Lewis,

  • Molly Madden,

  • James R. Reddell,

  • Boris Sket,

  • Peter Trontelj,

  • Denis White


D. C. Culver (dculver@american.edu) and M. Madden, Dept of Biology, American Univ., 4400 Massachusetts Ave., NW, Washington, DC 20016, USA. – L. Deharveng and A. Bedos, UMR 5202 du CNRS, Museum National d'Histoire Naturelle, 45 Rue de Buffon, FR-75005, Paris, France. – J. J. Lewis, Lewis and Associates, 17903 State Road 60, Borden, IN 47106-8608, USA. – J. R. Reddell, Texas Memorial Museum, Univ. of Texas, 2400 Trinity Ave., Austin, TX 78705, USA. – B. Sket and P. Trontelj, Dept of Biology, Univ. of Ljubljana, Večna pot 111, p.p. 2995, SI-1001 Ljubljana, Slovenia. – D. White, Environmental Protection Agency, 200 SW 35th Street, Corvallis, OR 97333, USA.

Abstract

The world's obligate cave-dwelling fauna holds considerable promise for biogeographic analysis because it represents a large number of independent evolutionary experiments in isolation in caves and adaptation to subterranean life. We focus on seven north temperate regions of at least 2000 km2, utilizing more than 4300 records of obligate cave-dwelling terrestrial invertebrates. In North America, highest diversity was found in northeast Alabama while in Europe highest diversity was found in Ariège, France, and in southeast Slovenia. Based on these regions as well as more qualitative data from 16 other regions, we hypothesize that a ridge (ca 42°–46° in Europe and 34° in North America) of high biodiversity occurs in temperate areas of high productivity and cave density. This may reflect a strong dependence of cave communities on long term surface productivity (as reflected in actual evapotranspiration), because the subterranean fauna relies almost entirely on resources produced outside caves. This dependence may explain the unique biodiversity pattern of terrestrial cave invertebrates.

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