Multiple ecological pathways to extinction in mammals

doi:10.1073/pnas.0901956106

Multiple ecological pathways to extinction in mammals

^aInstituto de Ecología, Universidad Nacional Autónoma de México, Mexico, DF, 04510 MX;
Departments of ^bBiology and
^cAnthropology, University of New Mexico, Albuquerque, NM 87131;
^dEcology, Behavior & Evolution Section, Division of Biological Sciences, University of California, San Diego, CA 92093; and
^eSanta Fe Institute, Santa Fe, NM 87501

Edited by Paul R. Ehrlich, Stanford University, Stanford, CA, and approved May 5, 2009 (received for review February 24, 2009)

Abstract

As human population and resource demands continue to grow, biodiversity conservation has never been more critical. About one-quarter of all mammals are in danger of extinction, and more than half of all mammal populations are in decline. A major priority for conservation science is to understand the ecological traits that predict extinction risk and the interactions among those predictors that make certain species more vulnerable than others. Here, using a new database of nearly 4,500 mammal species, we use decision-tree models to quantify the multiple interacting factors associated with extinction risk. We show that the correlates of extinction risk vary widely across mammals and that there are unique pathways to extinction for species with different lifestyles and combinations of traits. We find that risk is relative and that all kinds of mammals, across all body sizes, can be at risk depending on their specific ecologies. Our results increase the understanding of extinction processes, generate simple rules of thumb that identify species at greatest risk, and highlight the potential of decision-tree analyses to inform conservation efforts.

Footnotes

¹To whom correspondence should be addressed. E-mail: davidson{at}unm.edu
Author contributions: A.D.D., M.J.H., A.G.B., G.C., and J.H.B. designed research; A.D.D., A.G.B., and M.J.H. performed research; A.D.D., A.G.B., and M.J.H. analyzed data; and A.D.D., M.J.H., A.G.B., J.H.B., and G.C. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0901956106/DCSupplemental.