一项研究发现，一场流行病消灭了巴拿马El Copé地区估计约30种两栖类物种，并将两栖类多样性降低了40%以上。越来越多的研究提示，全球两栖类种群的衰退是由于一种称为壶菌病（chytridiomycosis）的疾病造成。Andrew Crawford及其同事通过使用一种称为“DNA条码”的辨识技术比较了2000-2003年疾病流行前对两栖类种群的实地调查和2006-2008年疾病流行后的调查，从而对El Copé的两栖类丧失进行了量化。

在DNA条码技术中，能够唯一地辨认已知物种的短遗传序列被发现并储存在公共数据库中。通过在数据库中比较未知生物的DNA谱，科学家可以迅速地辨识生物样本，并构造遗传世系。

这组作者估计，El Copé地区的25种此前观察到的两栖类物种在这场疾病流行期间灭绝了，而且根据世系重建的结果，至少5种过去还未被观察到的物种也灭绝了。在总体上，该地区的两栖类多样性下降了40%以上。这组作者说，该研究还表明DNA条码技术可能用于迅速量化生态系统的多样性变化。

原文出处：

PNAS doi: 10.1073/pnas.0914115107

Epidemic disease decimates amphibian abundance, species diversity, and evolutionary history in the highlands of central Panama
Andrew J. Crawforda,b,c,1, Karen R. Lipsa,d, and Eldredge Berminghama

aSmithsonian Tropical Research Institute, Apartado 0843–03092, Panamá, Republic of Panama;
bDepartment of Biological Sciences, Universidad de los Andes, A.A. 4976, Bogotá, Colombia; cCírculo Herpetológico de Panamá, Apartado 0824-00122, Panamá, Republic of Panama; and dDepartment of Biology, University of Maryland, College Park, MD 20742-4415

Amphibian populations around the world are experiencing unprecedented declines attributed to a chytrid fungal pathogen, Batrachochytrium dendrobatidis. Despite the severity of the crisis, quantitative analyses of the effects of the epidemic on amphibian abundance and diversity have been unavailable as a result of the lack of equivalent data collected before and following disease outbreak. We present a community-level assessment combining long-term field surveys and DNA barcode data describing changes in abundance and evolutionary diversity within the amphibian community of El Copé, Panama, following a disease epidemic and mass-mortality event. The epidemic reduced taxonomic, lineage, and phylogenetic diversity similarly. We discovered that 30 species were lost, including five undescribed species, representing 41% of total amphibian lineage diversity in El Copé. These extirpations represented 33% of the evolutionary history of amphibians within the community, and variation in the degree of population loss and decline among species was random with respect to the community phylogeny. Our approach provides a fast, economical, and informative analysis of loss in a community whether measured by species or phylogenetic diversity.