title: Dark diversity: shedding light on absent species.
abstract: Ecological theory and nature conservation have traditionally relied solely on observed local diversity. In this review, we recommend including those species that are absent from an ecosystem but which belong to its species pool; that is, all species in the region that can potentially inhabit those particular ecological conditions. We call the set of absent species 'dark diversity'. Relating local and dark diversities enables biodiversity comparisons between regions, ecosystems and taxonomic groups, and the evaluation of the roles of local and regional processes in ecological communities. Dark diversity can also be used to counteract biodiversity loss and to estimate the restoration potential of ecosystems. We illustrate the dark diversity concept by globally mapping plant dark diversity and the local:dark diversity ratio.
authors.affiliation: Institute of Ecology and Earth Sciences, University of Tartu, Lai 40, Tartu 51005, Estonia. meelis.partel@ut.ee
authors.forename: Meelis
authors.initials: M
authors.lastname: Pärtel
authors.forename: Robert
authors.initials: R
authors.lastname: Szava-Kovats
authors.forename: Martin
authors.initials: M
authors.lastname: Zobel
mesh_terms: D044822:Biodiversity; D058448:Biota; D003247:Conservation of Natural Resources; D004463:Ecology / Q000379:methods*; D017753:Ecosystem; D010944:Plants / Q000145:classification*