|Secret extinctions: the loss of genetic diversity in forest ecosystems|
Ledig, F.T. (1993). Secret extinctions: the loss of genetic diversity in forest ecosystems, in: Fenger, M.A. et al. (Ed.) Our living legacy: Proceedings of a Symposium on Biological Diversity. pp. 127-140
In: Fenger, M.A. et al. (Ed.) (1993). Our living legacy: Proceedings of a Symposium on Biological Diversity. The Royal British Columbia Museum: Victoria. ISBN 0-7718-9355-8. XIII, 392 pp., more
The biodiversity crisis is usually equated with species extinctions, but much more common are the loss of genetic diversity through the extirpation of locally adapted populations and the reduction of genetic diversity within species. These local losses are the secret or hidden extinctions. They result in the erosion of genetic resources and affect the recovery of damaged ecosystems. In general, conservation efforts are justifiably focused on low latitudes, because genetic diversity among species, populations within species and individuals within species all tend to increase from high latitudes to the tropics. Likewise, loss of diversity from overexploitation and habitat destruction increases along the same gradient. Nevertheless, these losses, particularly tropical deforestation, will have severe impacts at northern latitudes because they contribute to the Greenhouse Effect and global warming. Conservation through the establishment of reserves and through seed banks is important, but reserves and seed banks in themselves are insufficient to halt the loss. Conservation must be a factor in all land-management activities.