Present address: Department of Biology, University of Maryland, College Park, MD 20742-4415, USA.
Selecting for extinction: nonrandom disease-associated extinction homogenizes amphibian biotas
Article first published online: 20 AUG 2009
© 2009 Blackwell Publishing Ltd/CNRS
Volume 12, Issue 10, pages 1069–1078, October 2009
How to Cite
Smith, K. G., Lips, K. R. and Chase, J. M. (2009), Selecting for extinction: nonrandom disease-associated extinction homogenizes amphibian biotas. Ecology Letters, 12: 1069–1078. doi: 10.1111/j.1461-0248.2009.01363.x
- Issue published online: 10 SEP 2009
- Article first published online: 20 AUG 2009
- Editor, Peter Thrall Manuscript received 2 March 2009 First decision made 2 April 2009 Second decision made 7 July 2009 Manuscript accepted 15 July 2009
- Amphibian chytrid;
- amphibian declines;
- beta diversity;
- biotic homogenization;
- wildlife disease
Studying the patterns in which local extinctions occur is critical to understanding how extinctions affect biodiversity at local, regional and global spatial scales. To understand the importance of patterns of extinction at a regional spatial scale, we use data from extirpations associated with a widespread pathogenic agent of amphibian decline, Batrachochytrium dendrobatidis (Bd) as a model system. We apply novel null model analyses to these data to determine whether recent extirpations associated with Bd have resulted in selective extinction and homogenization of diverse tropical American amphibian biotas. We find that Bd-associated extinctions in this region were nonrandom and disproportionately, but not exclusively, affected low-occupancy and endemic species, resulting in homogenization of the remnant amphibian fauna. The pattern of extirpations also resulted in phylogenetic homogenization at the family level and ecological homogenization of reproductive mode and habitat association. Additionally, many more species were extirpated from the region than would be expected if extirpations occurred randomly. Our results indicate that amphibian declines in this region are an extinction filter, reducing regional amphibian biodiversity to highly similar relict assemblages and ultimately causing amplified biodiversity loss at regional and global scales.