title: The biodiversity of species and their rates of extinction, distribution, and protection.
abstract: Recent studies clarify where the most vulnerable species live, where and how humanity changes the planet, and how this drives extinctions. We assess key statistics about species, their distribution, and their status. Most are undescribed. Those we know best have large geographical ranges and are often common within them. Most known species have small ranges. The numbers of small-ranged species are increasing quickly, even in well-known taxa. They are geographically concentrated and are disproportionately likely to be threatened or already extinct. Current rates of extinction are about 1000 times the likely background rate of extinction. Future rates depend on many factors and are poised to increase. Although there has been rapid progress in developing protected areas, such efforts are not ecologically representative, nor do they optimally protect biodiversity.
authors.affiliation: Nicholas School of the Environment, Duke University, Box 90328, Durham, NC 27708, USA. stuartpimm@me.com.
authors.forename: S L
authors.initials: SL
authors.lastname: Pimm
authors.affiliation: Instituto de Pesquisas Ecológicas, Rodovia Dom Pedro I, km 47, Caixa Postal 47, Nazaré Paulista SP, 12960-000, Brazil.
authors.forename: C N
authors.initials: CN
authors.lastname: Jenkins
authors.affiliation: Post Office Box 402 Haverford, PA 19041, USA.
authors.forename: R
authors.initials: R
authors.lastname: Abell
authors.affiliation: International Union for Conservation of Nature, IUCN, 28 Rue Mauverney, CH-1196 Gland, Switzerland.
authors.forename: T M
authors.initials: TM
authors.lastname: Brooks
authors.affiliation: Odum School of Ecology, University of Georgia, Athens, GA 30602, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Gittleman
authors.affiliation: Microsoft Research, 21 Station Road, Cambridge, CB1 2FB, UK.
authors.forename: L N
authors.initials: LN
authors.lastname: Joppa
authors.affiliation: Missouri Botanical Garden, Post Office Box 299, St. Louis, MO 63166-0299, USA.
authors.forename: P H
authors.initials: PH
authors.lastname: Raven
authors.affiliation: Environment Department, University of York, York, YO10 5DD, UK.
authors.forename: C M
authors.initials: CM
authors.lastname: Roberts
authors.affiliation: Global Land Cover Facility, Department of Geographical Sciences, University of Maryland, College Park, MD, 20742, USA.
authors.forename: J O
authors.initials: JO
authors.lastname: Sexton
mesh_terms: D000818:Animals; D044822:Biodiversity; D003247:Conservation of Natural Resources / Q000379:methods*; D056727:Endangered Species; D053476:Extinction, Biological; D005843:Geography; D006801:Humans; D011157:Population Dynamics